3Cosmetic uses of Botulinum toxin A in the upper face

INTRODUCTION

Botulinum neurotoxin (BoNT) has taken the practice of medicine by surprise and with a furor. Rarely can one find such an ordinary protein that in its natural form is so deadly, but by purification and extraction techniques can be utilized for therapeutic and cosmetic purposes by both physicians and surgeons. The utilization of BoNTs in neuromuscular disorders has provided fortuitous relief for many tormented with incurable diseases, affording them an encouraging respite from their devastating afflictions. The countless possibilities for the use of BoNT in clinical medicine are continuously being discovered. For a wide range of medical and surgical specialists, including neurologists, physiatrists, ophthalmologists, otolaryngologists, gastroenterologists, urologists, and now even dermatologists, cosmetic and aesthetic physicians and surgeons, BoNT has proven to be a powerful adjunctive modality for a multitude of disorders.

Although this text is not the first one concerned with the use of BoNT, it is one of the few texts to address the use of BoNT solely for dermatological, cosmetic, and aesthetic purposes. In the United States injecting BoNT for cosmetic and aesthetic purposes for any reason other than to diminish glabellar frown lines is considered off-label use and not Food and Drug Administration (FDA) approved. Whether or not the FDA and other governmental regulatory agencies in other countries will ever approve every single indication for which the BoNTs have proven to be efficacious, the fact remains that BoNTs are extremely reliable, nontoxic, and safe. BoNTs, provide reproducible results when administered as prescribed. Consequently, BoNTs are quickly becoming a part of the armamentarium of many physicians and surgeons worldwide.

In these subsequent three chapters on the cosmetic use of BoNT in the face and body in order to avoid ambiguity and confusion with the injection of appropriate and effective doses of BoNT, any reference to Botulinum neurotoxin serotype A (BoNTA), will denote explicitly and specifically BOTOX® Cosmetic (onabotulinumtoxinA). The treatment of patients with onabotulinumtoxinA for dermatological, cosmetic, and aesthetic purposes is presented in a systematic fashion, first by identifying the anatomical basis of different unaesthetic changes acquired by men and women as they “age” and “wrinkle.” Next, normal functional anatomy is discussed to elucidate the reasons for these displeasing changes so that a suitable plan of correction with onabotulinumtoxinA can be initiated. The anatomical drawings used to illustrate normal anatomy of facial muscles (see chaps. 2–5) will depict superficial musculature on the left side of the figure and deeper musculature on the right. Functional anatomy is emphasized because the only way to utilize any type of BoNT properly is to have an in-depth understanding of how to modify the normal movements of facial mimetic muscles and other muscles elsewhere on the body. When injections of onabotulinumtoxinA are appropriately performed, desirable and reproducible results without adverse sequelae are created. In this and the next two chapters, suggestions will be made on how much to reconstitute a vial of onabotulinumtoxinA to arrive at various preferred dilutions for different anatomical sites. The FDA-approved manufacturer’s recommendation for product reconstitution is to use 2.5 ml of nonpreserved normal saline. The approved and recommended dilution is for glabellar frown lines only, since this is the only FDAapproved indication for the cosmetic use of onabotulinumtoxinA. However, when treating other areas of the face and body for cosmetic purposes, albeit in an

off-label, unapproved manner, higher or lower dilutions of onabotulinumtoxinA prove to be clinically more appropriate, depending on the muscles being treated. Precise dosing and accurate injections of onabotulinumtoxinA will modify muscle movements of the face and body in a safe and reproducible way. This in turn can be used to improve a particular aesthetic problem reliably and for extended periods of time. Also, emphasis is placed on what to do and what not to do when injecting onabotulinumtoxinA. Outcomes and results of different injection techniques specifically only for onabotulinumtoxinA are discussed so as to avoid adverse sequelae and complications.

Some may criticize the “cookbook” approach of these chapters. However, this systematic detailing of where, why, and how much onabotulinumtoxinA to inject is necessary to understand when treating a certain problem in a particular area of the body, and, therefore, this detailing was done intentionally. It is important to note, however, that the face is the only area of the body where the muscles attach directly underneath the skin. Consequently, when these muscles contract, they move the skin of the face (hence the designation “mimetic facial muscles”), producing folds and wrinkles always in a perpendicular orientation to the direction of muscle contraction. Nowhere else in the body are there similar mimetic muscles that contract voluntarily or involuntarily whereby nonverbal communication intentionally or unintentionally is expressed. The reader must never lose sight of the fact that every single individual patient is different and should never be treated in an identical way without justification. These next three chapters strive to provide both the neophyte and experienced physician the rationale for why and how a patient should be treated with a particular amount of onabotulinumtoxinA in one area or another for a distinct, reproducible outcome. By explicitly presenting certain techniques and the reasons for their use, the reader also needs to understand that this is only the author’s perception and interpretation of a given aesthetic problem and his approach to managing the problem, for that patient, who may or may not present again in the future in exactly the same way (see chap. 1). Consequently, when a physician is preparing to treat a patient with onabotulinumtoxinA, it does not matter if the patient is new or one who has been treated before, the physician should approach that patient as if he or she were receiving onabotulinumtoxinA for the first time. The physician must comprehensively evaluate the patient’s current aesthetic problem prior to commencing with the injections of onabotulinumtoxinA and not necessarily rely totally on past treatment dosing. The physician should be flexible and treat the patient’s concerns and specific offending changes that are present at the time. Treat the patient, not the picture.

Clinical examples and solutions presented in these next three chapters are only paradigms of reasonably acceptable clinical outcomes. The reader therefore should be able to extrapolate for himself or herself a preferred approach and injection technique when treating patients with similar clinical problems, provided there is sound justification for such a manner of treatment.

In 1989, onabotulinumtoxinA, known at that time as Oculinum, was first approved by the FDA in the United States for the treatment of strabismus and blepharospasm. By 2000, onabotulinumtoxinA now called BOTOX® was approved by the FDA for the treatment of cervical dystonia. In 2002, the FDA approved BOTOX® for the cosmetic purpose of treating glabellar frown lines. This resulted in the manufacturer’s designation of the brand name BOTOX® Cosmetic. In 2009 both BOTOX®

and BOTOX® Cosmetic were assigned the nonproprietary name of onabotulinumtoxinA by the FDA. In the not too distant future, new and different formulations of BoNTA other than onabotulinumtoxinA will be approved for use in the United States for both therapeutic and cosmetic uses. The first of these is Dysport® (abobotulinumtoxinA), which was recently (May 2009) approved by the FDA and is discussed in-depth in chapter 9 along with other formulations of BoNTA not yet available in the United States. In order to distinguish the current and future different formulations of BoNTA from one another without mentioning their tradenames or brand names, the FDA has assigned nonproprietary names, a type of “generic” name, to the different formulations of the BoNTs. OnabotulinumtoxinA was assigned to BOTOX® and BOTOX® Cosmetic; and abobotulinumtoxinA was assigned to Dysport®. Botulinum neurotoxin type B (BoNTB) known as MyoblocTM in the United States and NeuroblocTM in Europe was assigned the name rimabotulinumtoxinB; FDA-approved and available in the United States, rimabotulinumtoxinB is discussed in chapter 10.

The different formulations and brand names of BoNTA that are currently in use in other parts of the world outside of the United States are still being measured and defined for equivalency with onabotulinumtoxinA. It is extremely important to understand that the specific units and dosages of the BoNTA discussed in chapters 3 to 5, are only for onabotulinumtoxinA (i.e., BOTOX® Cosmetic) unless explicitly stated otherwise. The same number of units specifically identified and detailed here for onabotulinumtoxinA (BOTOX® Cosmetic) absolutely cannot be used with the identical unit dose to treat patients with BoNTA of another source or manufacturer, even if a ratio of equivalency is provided as being 1:1. Injectors of onabotulinumtoxinA (BOTOX® Cosmetic) have quickly learned from their frustrating experiences in the past when using rimabotulinumtoxinB (Myobloc/ Neurobloc) that comparative equivalencies are not easily extrapolated. Not only was it difficult to establish a conversion dosage for equating rimabotulinumtoxinB with onabotulinumtoxinA, it also was found that a muscle in a particular area of the face or body did not respond equivalently with a fixed dose conversion ratio of rimabotulinumtoxinB with onabotulinumtoxinA (see chap. 1) (1). The dose conversion ratio was even found to be different when similar or adjacent muscles in the same patient were treated. For example, if the average equivalency unit dose was found to be 150:1 (i.e., units of rimabotulinumtoxinB to units of onabotulinumtoxinA) when treating the frontalis with rimabotulinumtoxinB, then one naturally assumed the same equivalency ratio would be applicable for treating any of the other mimetic muscles of the face. However, when rimabotulinumtoxinB was used for another facial muscle, for example, the orbicularis oculi or corrugator supercilii, the equivalency of rimabotulinumtoxinB to

onabotulinumtoxinA was not the same, but namely 125:1, or thereabout. Diffusion characteristics and rates also seem to influence the inability to establish any type of fixed conversion ratio between rimabotulinumtoxinB with onabotulinumtoxinA. Therefore the equivalent dose ratio for rimabotulinumtoxinB could not be fixed, at least in the author’s personal experience. This confounding of dose equivalencies using onabotulinumtoxinA (i.e., BOTOX® Cosmetic) as the standard to which all other serotypes of BoNT are measured will only become compounded when different formulations of BoNTA or other BoNT serotypes are administered, and the reasons for this are briefly touched upon in chapters 1, 9, and 10. Therefore, when using any other type of BoNT other than onabotulinumtoxinA (i.e., BOTOX® Cosmetic), it is imperative that one learns how to administer that particular type of BoNT independently of any conversion ratios, because individual muscles may respond in a distinctly different manner with certain formulations and specific serotypes of BoNT (2).

The understanding of the pharmacokinetics and pharmacodynamics of BoNT is still only in its early stages, and the possibilities for future developments are boundless. It is intriguing to understand that the cosmetic use of onabotulinumtoxinA was initiated by the insight and convictions of two astute and courageous physicians, an ophthalmologist wife and her dermatologist husband. If it were not for the persistence of Jean and Alastair Carruthers in promoting their serendipitous observations, many other perceptive and insightful physicians would not have had the opportunity or confidence to learn more about BoNT and its use in clinical aesthetic medicine. The challenge now being passed onto the reader is that with some basic knowledge of how to inject a few drops of BoNT appropriately and safely; while treating patients with compassion and professionalism, additional innovative and ingenious uses of BoNT can be uncovered, be they for cosmetic or therapeutic purposes (Fig. 3.1).

CENTRAL BROW (GLABELLAR) FROWN LINES

Introduction: Problem Assessment and Patient Selection

The area most frequently treated with BoNT is the central brow or glabella and its frown lines (3–13). The glabella is the smooth, flat, triangular elevation of the frontal bone superior to the nasal radix positioned between the two superciliary ridges or arches. On the skin surface, the glabella is the space between the eyebrows. The muscles of the “glabellar complex” were the first and currently the only muscles of the face or body into which onabotulinumtoxinA can be injected for cosmetic purposes that have been approved in the United States by the FDA. Treatment of all other muscles in any other part of the face or body with injections of onabotulinumtoxinA for cosmetic reasons is done solely and expressly in an off-label, nonapproved manner.

There are four depressor muscles of the brow that cause the horizontal and vertical creases of the glabella. These muscles allow one to squint to protect the eyes from projectiles, gusts of air, and the elements (i.e., glaring light, wind, dust, sand, etc.) by lowering the eyebrows and adducting them medially. However, hyperkinetic depressor muscles can cause persistent, unintentional adduction and lowering of the medial aspect of the eyebrows, causing wrinkling between the eyes. For example, this central brow frowning during moments of intense concentration can be misinterpreted by others as a veritable frown, which usually expresses negative feelings of concern, tiredness, disappointment, frustration, anger, pain, suffering, etc. (Fig. 3.1A). Weakening the four depressors of the glabella with injections of onabotulinumtoxinA can raise the eyebrows and virtually eliminate the frown lines of the glabella. This allows a person to appear more relaxed, conveying a positive sentiment when one ordinarily might be frowning and expressing a negative demeanor (Fig. 3.1B). An elevated brow generally expresses a positive attitude, whereas a depressed brow expresses a negative one. In addition, low-set eyebrows may promote the formation of upper eyelid and lateral canthal hooding (Fig. 3.2). Arched or peaked eyebrows usually are more attractive in women whereas men in general prefer more horizontal eyebrows. However, beware of women who pluck or have had permanent tattooing of their eyebrows, because the natural position of their brows may be deceptively displaced (14,15).

The overall contour and shape of the eyebrows depend on many factors, including age, sex, culture, ethnicity, and current fashion trends (16). The size, shape, and position of the eyebrows can vary widely, depending on the shape of the face (i.e., oval, round, square, or long/ narrow) (Fig. 3.3A,B) (17). In the literature and in clinical practice, there really is no rigid definition or description of the “ideal eyebrow” that can be applied to all faces universally. Eyebrows that appear aesthetically pleasing on one face may look abnormal and unattractive on another face. Therefore, a detailed pretreatment assessment of how an individual’s eyebrow position and shape conforms to the “ideal brow” contour for that particular individual is vital to producing acceptable results with injections of onabotulinumtoxinA.

The brow has both static and dynamic qualities of beauty and expressiveness that change with advancing age (18). This is seen as brow ptosis in varying degrees, which can modify the shape and position of the brows, thereby compromising the youthful appearance and aesthetic attractiveness of a person. The ideal contour of the female eyebrow as outlined by Westmore (16,18) is typical of an oval face. The medial brow should begin on the same vertical plane as the lateral extent of the ala and the inner canthus (Fig. 3.4A,B). The eyebrow should end laterally (Fig. 3.4C) where it meets an oblique line drawn from the most lateral point of the ala (Fig. 3.4A) through the lateral canthus. The medial and lateral ends of the eyebrow (Fig. 3.4B,C) lie on approximately the same horizontal plane. The apex of the arc of the eyebrow lies on a vertical line (Fig. 3.4D,E) directly above the lateral limbus of the iris of the eye (19). The tail (lateral aspect) of the eyebrow can lie 1 to 2 mm above the lowest point of its head (medial aspect) on the horizontal plane (Fig. 3.4B,C). In addition, according to Angres, one also should take into account the patient’s intercanthal distance when assessing a patient’s eyebrow position (15). If the intercanthal distance is normal, the brow should start at a vertical line that bisects the medial canthus (Fig. 3.4A,B). However, if the intercanthal distance is increased, the eyebrow should begin medial to the medial canthus. On the other hand, a narrower intercanthal distance requires the eyebrow to start lateral to the vertical line, that is, the medial canthus (Fig. 3.4A,B).

Finally, when the face is not oval, additional modifications to Westmore’s “ideal brow” may be necessary (Fig. 3.3B). For example, a square face favors soft curves with the apex of the arch lateral to the lateral limbus and the tail of the eyebrow directed at the center of the ear. A long/thin face may look more attractive with a straighter, less-arched

Figure 3.2 Low set eyebrows promote upper eyelid and lateral canthal hooding in this 59-year-old patient.

eyebrow, with the tail pointing closer to the top of the ear. This visually will avoid elongating an already long face. A round face is enhanced with a high arch that also points to the top of the ear to enhance the angularity of the ear. Lastly, the overall silhouette of a female eyebrow should be that of the wing of a gull (Fig. 3.5).

The male eyebrow normally has less of an arc than the female eyebrow and is usually flatter or nearly horizontal (Fig. 3.6). It typically should be positioned lower on the superciliary arch just above the superior bony orbital margin. Also, the lateral aspect of the male eyebrow is usually more prominent. The pretreatment position and symmetry of the eyebrows and eyelids will dictate the technique that will be needed to treat the glabellar frown lines. In women whose eyebrows are barely arched, strategically placed injections of onabotulinumtoxinA into the brow depressors, can elevate the eyebrows by allowing the lower fibers of the frontalis to raise the eyebrows unopposed by the decussating fibers of the corrugator supercilii, procerus and orbicularis oculi (Fig. 3.7A,B) (14).

Trindade de Almeida has classified glabellar frown lines into five distinct patterns (20). Although the muscular anatomy is by and large alike in most patients, individual skeletal morphology and idiosyncratic muscular movements can produce unique variations in the pattern of wrinkles in the glabellar area as well as anywhere else on the face during intentional animation and spontaneous expression. These differences in glabellar wrinkle patterns indicate that the strength of each glabellar muscle is not identical and uniform in every patient and one set of muscles may be stronger or weaker than its codepressor set of muscles. Their response to neurostimulation also is uniquely different in every individual. Therefore, the pattern of glabellar frowning is dependent upon which muscles are stronger or weaker, and the injected dose of onabotulinumtoxinA must vary accordingly. Some glabellar wrinkle patterns are observed more frequently than others according to Trindade de Almeida (Fig. 3.8A–E) (20).

Functional Anatomy (see Appendix 1)

Contracting any of the mimetic muscles of the face will cause wrinkling of the skin perpendicular to the orientation of those muscle fibers and the direction of their movement. Therefore, the muscles that produce the vertical lines of the glabella because their fibers are oriented more or less horizontally are the medial brow depressors, that is, corrugator supercilii, and the medial fibers of the orbital orbicularis oculi.

The corrugator supercilii is a small, narrow, deeply situated paired muscle that arises just inferior to the medial aspect of the superciliary

arch approximately 4 mm lateral to the nasion (Fig. 3.9). The nasion is the point of juncture of the nasofrontal with the internasal bony sutures (21). Clinically it can be palpated as the center of the concavity at the nasal radix (or root). The corrugator supercilii extends laterally and upwardly through the palpebral and orbital fibers of the orbicularis oculi, inserting into the soft tissue and skin above the middle of the eyebrow in the vicinity of the midpupillary line and the supraorbital notch. The bulk of the corrugator supercilii can be found overlying

the inferior aspect of the superciliary arch (Fig. 3.10) (21,22). It lies directly against the bone and just beneath the interdigitating muscle fibers of the orbicularis oculi, procerus, depressor supercilii, and frontalis medially and beneath interdigitating fibers of the frontalis and orbicularis oculi laterally (Fig. 3.9). Anatomic studies have demonstrated that the thickest portion of the belly of the corrugator is at or just above a horizontal plane drawn through the middle of the eyebrow and approximately 2.0 cm from the nasion (Fig. 3.10A,B) (19,21,23).

E

C B

D

A

Figure 3.4 The peak of the arch of a female brow should be just above the lateral limbus. The tail of the brow should be on a horizontal plane 1–2 mm above the lowest point of its head.

Figure 3.5 The ideal eyebrow of a woman outlines the wing of a gull.

The outermost fibers of the orbicularis oculi are called the orbital portion of the orbicularis oculi. The orbital orbicularis oculi arises from the bony structures of the lateral nose and medial orbit, including the medial canthal ligament. Its fibers then run superiorly and inferiorly, forming a wide sphincteric ring around the bony orbit that extends beyond the edges of the bony orbital rim and into the eyelids (Fig. 3.11). The medial aspect of the orbital orbicularis oculi occasionally is referred to as the depressor supercilii by some

Figure 3.6 The ideal eyebrow of a man is less arched and lower set than a woman’s.

authors. Contraction of the orbital orbicularis oculi approximates the upper with the lower eyelids, either deliberately or involuntarily. The inner portion of the orbicularis oculi overlies the eyelid and is identified as the palpebral portion of the muscle. The palpebral orbicularis oculi is subdivided into the preseptal and pretarsal portions (Fig. 3.11).

The horizontal lines of the glabella and nasal root are produced by the contraction of the vertically oriented fibers of the procerus, depressor supercilii, and the medial fibers of the orbital orbicularis oculi. These three muscles also are referred to as the medial brow depressors. The procerus is a thin, pyramidal muscle centrally located in the midline between the two eyebrows. It lies 1 to 4 mm beneath the surface of the skin (Fig. 3.12). The procerus arises from the fascia covering the nasal bridge and lower part of the nasal bone and the upper part of the upper lateral nasal cartilage. It inserts superiorly into the skin and subcutaneous tissue at the nasal radix and lower part of the forehead between the two eyebrows. Contraction of the procerus pulls the medial aspect of the eyebrows downward, creating the horizontal frown lines across the root of the nose. Anatomic studies have demonstrated that the procerus can be longer in women than in men and, at times, bifid similar to the frontalis (23,24).

The depressor supercilii is considered by many a component part of the medial fibers of the orbital orbicularis oculi (Fig. 3.13) (19). Yet others consider it a separate and distinct muscle from the orbicularis oculi and corrugator supercilii (25). The depressor supercilii is a small muscle that has been found to originate directly from bone as one or two distinct muscle heads from the nasal process of the frontal bone and the frontal process of the maxilla, approximately 10 mm above the medial canthal tendon (25). In cadaver dissections where the depressor supercilii originated as two separate heads, the angular vessels passed in between the two bundles of muscles (25). In cadavers where there was only one head originating at the medial canthus, the angular vessels were found coursing anteriorly to the muscle. The depressor supercilii then passed vertically upward to insert into the undersurface of the skin at the medial aspect of the eyebrow, approximately 13 to 14 mm superior to the medial canthal tendon. It appeared superior in orientation to the medial aspect of the orbital orbicularis oculi (25). Not only does it help move the eyebrow downward and close the eyelid, but the depressor supercilii also participates in the functioning of the physiological lacrimal pump by compressing the lacrimal sac.

Opening and closing the eyes is partially accomplished by the contraction of the accessory muscles of the upper eyelid: one being the levator palpebrae superioris, a striated muscle, the other a nonstriated, smooth muscle called the superior tarsal or Müller’s muscle. The levator palpebrae superioris is the main retractor of the upper eyelid. It is a thin, flat, triangular sheet of striated muscle originating at the apex of the orbit at the common tendinous ring or annulus of Zinn on the lesser wing of the sphenoid behind the globe and just above the origin of the superior rectus muscle (Fig. 3.14) (1,26). The levator palpebrae superioris is positioned superior to the superior rectus as they both

pass over the superior aspect of the eyeball within the bony orbit. Approximately at the level of Whitnall’s transverse suspensory ligaments, the superior rectus attaches to the superior aspect of the globe at the level of the superior-conjunctival fornix, while the levator palpebrae superioris continues anteriorly as a wide aponeurosis. As the aponeurosis continues forward, some of its tendinous fibers attach to the anterior surface of the tarsus, and the rest pass in between the muscle fibers of the pretarsal orbicularis oculi and attach to the undersurface of the eyelid skin. Its tendinous attachments in the upper eyelid are responsible for the formation of the superior eyelid crease (Fig. 3.15).

Depressor supercilii

Orbicularis oculi

Levator labii superioris alaeque nasi

Compressor naris

Dilator naris

Zygomaticus

minor

Zygomaticus

major

Depressor

septi nasi

Risorius

Orbicularis oris

Modiolus

Platysma

Depressor anguli oris

Figure 3.12

Corrugator supercilii

Levator labii superioris alaeque nasi

Levator labii superioris

Levator anguli oris

Buccinator

Masseter

Depressor labii inferioris

Mentalis

The procerus is the midline, deep muscle of the glabella.

Dosing: How to Correct the Problem (see Appendix 3) (What to Do and What Not to Do)

The pretreatment evaluation should include examining the patient at rest and in full motion. Lightly palpate the muscles of the glabellar area with the palmar surface of the finger tips as the person squints

and frowns. This will help determine the location, size, and strength of the individual muscles of the glabella. A frequently used and standardized technique for treating the glabella is to inject onabotulinumtoxinA into five different sites with doses that range anywhere from 4 to 10 U or more at each site (Fig. 3.17) (7–13,27). Electromyographic

Dural sheath

Subarachnoid space

Inferior rectus

Orbicularis oculi

Levator palpebrae superioris

Superior conjunctival fornix

Superior rectus

Intraconal fat

Superior tarsal muscle of Müller (smooth)

Sclera

Bulbar and palpebral conjunctiva

Superior tarsal plate

Eyeball

Palpebral fissure

Cornea

Inferior conjunctival sac

Inferior conjunctival fornix

Orbital septum

Inferior check ligament

Ciliary glands

Cilia

(A)

Frontal bone

Insertion of levator palpebrae superioris muscle

and aponeurosis

Orbital septum

Superior tarsus

Lateral palpebral ligament and overlying raphe

Inferior tarsus

Orbital septum

Zygomatic bone

Supraorbital artery and nerve Supratrochlear artery and nerve

Dorsal nasal artery and infratrochlear nerve

Lacrimal sac

Medial palpebral ligament Maxilla (frontal process) Infraorbital artery and nerve

Figure 3.16 A 3/10 ml Becton-Dickinson insulin U-100 syringe with a 31-gauge needle swaged directly onto the syringe. Note the absence of any dead space between the hub of the needle and the neck of the syringe. Each unit notch on the barrel corresponds to 0.01 ml or 1 U.

guidance in this area has not particularly improved treatment outcomes because these facial muscles are superficial and easily localized by palpation and topographical landmarks (12,21,23, 29–33).

Patients who possess thinner, less sebaceous skin with finer wrinkles and shallower skin furrows and folds that can be spread apart and

reduced with the fingers (“glabellar spread test”) seem to have better, longer-lasting results (13). There are, however, some patients who are more difficult to treat because they are less responsive to the effects of onabotulinumtoxinA. In this group of patients who are more difficult to treat, there is one type of patient who possesses thick sebaceous skin with deep, intractable wrinkles whose furrows are difficult to pull apart with the fingers. Usually these turn out to be men and sometimes women who spend a lot of time outdoors. The other type are those who possess the inelastic, redundant skin seen with dermatochalasis and whose furrows are also deep but very easy to pull apart. These patients characteristically are older and unfortunately are not ideal candidates for glabellar chemodenervation, because frequently their final outcomes are less than ideal. Typically, in these patients, after having onabotulinumtoxinA injected with impeccable technique, the resultant relaxation of the glabellar muscles causes in folding of the lax and redundant glabellar skin. Consequently, there remains some evidence of frown lines and wrinkles even if higher doses of onabotulinumtoxinA are subsequently injected.

Generally, glabellar frown lines in women can be satisfactorily treated with a total dose of about 20 to 30 U or more of onabotulinumtoxinA injected into the standard five injection sites (Fig. 3.18) (4,11,29,39–45). Men, on the other hand, usually require a significantly higher dose of onabotulinumtoxinA (40–80 U) injected at seven sites across the glabella and medial brow to produce a reasonable effect that lasts at least 3 to 4 months (Fig. 3.19) (3,33–36). When glabellar lines

are deeper, longer, or thicker on one side of the midline, that set of medial depressors muscles (e.g., corrugator supercilii, depressor supercilii, and medial aspect of the orbital orbicularis oculi) should receive a slightly higher dose of onabotulinumtoxinA than the medial depressors on the contralateral side. The two injection points in addition to the standard five are those given over the midpupillary line, bilaterally, which usually are needed when treating men, so that the mid brow does not elevate and become more arched than is generally the case naturally (Fig. 3.20A–D) (37). Remember to remain at least 1 to 2 cm above the orbital rim at the midpupillary line to avoid blepharoptosis.

Some injectors have felt that the glabella should be treated separately and in one session first, before the frontalis is treated in a subsequent session, especially with first-time patients (3,34). They feel that some of the frontalis will be influenced by the diffusion of onabotulinumtoxinA when the glabella is treated first (14). This consequently can reduce the amount of wrinkling remaining on the forehead. This in turn lowers dosage requirements and may change the injection pattern necessary to treat the frontalis. Ultimately this may produce a better final result. Recently, however opinions have reversed and more and more injectors currently are treating the forehead and the glabella during the same session, and results seem to be comparable and just as effective (Figs. 3.20A and 3.21A,B) (34,38).

Treating glabellar lines with onabotulinumtoxinA and producing optimal results is not a simple task. There have been many injection patterns reported in the literature over the years, and they all produce optimal

results when the ideal patient is treated properly with a given injection pattern. This leads one to believe that any injection pattern will work and so injecting onabotulinumtoxinA is easy. However, this is not quite the case.

What is most important is the evaluation of the patient, and the treating physician’s understanding of why certain wrinkles are formed and which muscle(s) are creating them. Once a sound assessment is made and a justifiable treatment approach is designed, then it does not matter which of the injection patterns one uses. Patients should be treated individually according to their idiosyncratic pattern of muscle movement. A three, five, seven, or even more injection point pattern can be used if it is appropriate for that particular patient (4,20,39). Treat the patient, not the picture. However, the novice injector needs a point of reference; a standard of injection patterns to guide one during the early treatment sessions. As the neophyte injector acquires a better understanding of the functional anatomy and its responses to different patterns of injections with onabotulinumtoxinA, then a more directed and individualized approach to onabotulinumtoxinA injections will automatically develop (see Trindade de Almeida patterns below) (40). Do not forget to identify, photograph, and indicate to the patient prior to all onabotulinumtoxinA injections any variation in the anatomy that might be present and cause the patient’s eyebrows to be asymmetric. It appears that as much as 45% to 65% of the general female population has some form of brow asymmetry prior to ever being treated with a BoNT (author’s personal observation). Written documentation of the conversation about a patient’s idiosyncrasies and asymmetries is

absolutely necessary and must be completed along with a written record of the patient’s acknowledgement and response before ever initiating treatment with onabotulinumtoxinA.

In order to treat the glabellar frown lines and produce optimal, reproducible results with the least amount of complications, it is recommended that precise injections of relatively concentrated doses and low volumes be used on both sides of the midline whether or not the doses are equal. With the patient sitting up or in the semireclined position gently palpate the medial aspect of the eyebrows as the patient squints and frowns. After locating the belly of the corrugator supercilii with the pads of the second and third fingertips of the nondominant hand, ask the patient to raise the eyebrows as high as possible, keeping the tip of the index finger positioned over the thickest part of the belly of the corrugator supercilii. Prior to inserting the needle, the index finger of the nondominant hand should be advanced slightly cephalad and above the point of maximal muscle thickness. This usually is just above the eyebrow. The thumb now is placed at the margin of the supraorbital bony rim. The needle then is guided over the upper edge of the thumb, between it and the index finger, and inserted into the skin at a 60° to 90° angle until penetration into the corrugator supercilii can be felt (21,33). Entry into the corrugator is usually discerned

when, after passing through the dermis and subcutaneous tissue, an abrupt release of resistance is felt as the needle penetrates fascia and muscle fibers of the corrugator. At this point, the needle may or may not impinge onto the bone. If it does, the patient will sense sharp pain. The needle should then be withdrawn gently enough to move away from the bone, but not enough to exit the belly of the corrugator. The bore of the needle tip should be pointed upward and away from the globe, as it is slowly advanced into the belly of the corrugator supercilii in an oblique direction, slightly upward and lateral. Always remain deep within the muscle and medial to the supraorbital notch and approximately 1.5 to 2.0 cm superior to the supraorbital bony margin (Fig. 3.22). Refrain from striking the frontal bone with the needle tip, so as not to inflict any additional pain upon the patient, which occurs when periosteum is pierced. However, this may not be avoidable when first learning how to find the deeply seated corrugators and effectively inject them at the proper depth. Placing the nondominant index finger and thumb on the brow just above and below the eyebrow prior to injecting onabotulinumtoxinA serves many purposes. It prevents injecting onabotulinumtoxinA too low and close to the orbital rim. By applying direct pressure with the thumb inferior to the border of the supraorbital bony rim, Binder et al. felt that they were able to reduce

Figure 3.22 Technique of injecting the corrugator supercilii (note the position of the thumb and index finger of the nondominant hand).

Figure 3.23 Technique of injecting the medial aspect of the orbicularis oculi and depressor supercilii (note the position of the index finger and the thumb of the nondominant hand).

migration of onabotulinumtoxinA behind the orbital septum (21,33). This maneuver also assists in identifying the location and direction of the corrugator supercilii, because it can be felt by light palpation. It also is important to inject slowly to avoid dispersing the onabotulinumtoxinA to surrounding, nontargeted muscles. Now inject 4 to 10 U of onabotulinumtoxinA into the strongest portion of the muscle, which is located approximately 2 cm superior and 2 cm lateral to the nasion or the center of the concavity at the nasal root (Figs. 3.9 and 3.10A,B) (21). Next withdraw the needle out of the skin and redirect the tip of the needle medially in the direction of the nasion. Insert the needle at or adjacent to the most medial aspect of the superciliary arch approximately 2 cm directly superior to the ocular caruncle at the inner canthus (Fig. 3.23). Injecting another 2 to 6 U of onabotulinumtoxinA at this point of maximum muscle contraction will treat the medial vertical muscle fibers of the orbital orbicularis oculi and the depressor supercilii. Because the fibers of the orbicularis oculi are closely adherent to the overlying skin, injections can be given either intradermally or in the superficial subcutaneous plane at this site. Superficial injections here also should affect the depressor supercilii and avoid puncturing the supratrochlear vessels and nerve. A pleasing vertically upward lift to the medial brow can be accomplished by this technique, if fibers of the frontalis are not inadvertently affected (41,42). Gentle massage in an upward and lateral direction for a few seconds immediately after the injection helps relieve the acute pain the patient might have experienced,

and can disperse the toxin into the areas intended for treatment. Heavy-handed massage will definitely disperse the onabotulinumtoxinA beyond the area and into muscle fibers not intended for treatment, that is, into the fibers of the lower frontalis, which can produce brow ptosis.

Next, watch as the patient frowns again, and notice to what extent the mid brow adducts toward the glabella. Stronger corrugators will visibly pull the skin just above the eyebrows medially. In some patients, additional corrugations vertically along the brow that are parallel to the central vertical glabellar lines also will be formed (Fig. 3.24A). These corrugations can be reduced by injecting 4 to 10 U of onabotulinumtoxinA deeply into the belly of the corrugator supercilii (i.e., at the medial aspect of the eyebrow) and 4 to 10 U intradermally near where the corrugators insert into the mid brow, which is just medial to the supraorbital notch or midpupillary line (Fig. 3.24B,C). The medial brow injections are given deeply directly into the belly of the corrugator, while the more lateral injections over the mid brow should be applied superficially since the fibers of the corrugators in this location are superficial and insert into the under surface of the skin (Fig. 3.25). These injections should reduce the adduction of the brow and eliminate corrugations.

Next, an injection of approximately 4 to 10 U of onabotulinumtoxinA is given between the eyebrows at the nasal root into the belly of the procerus and into the interdigitating fibers of the depressor

supercilii and medial fibers of the orbital orbicularis oculi (Fig. 3.26). The dose needed for this injection of onabotulinumtoxinA will depend upon the overall muscle strength and depth of the horizontal glabellar wrinkles that are present (23). The strength of the procerus can be determined by gently palpating the glabellar area with the pads of the second and third fingertips of the nondominant hand, while the patient repeatedly squints and frowns. Glabellar wrinkles tend to be deeply fixed in the skin, especially the horizontal ones. Those that are more resistant to treatment with onabotulinumtoxinA commonly are found in men and women who spend a lot of time outdoors, because their glabellar muscles are significantly hypertrophied from frequent squinting. Intramuscular instead of subcutaneous injections of onabotulinumtoxinA into the procerus can be accomplished by gently grasping the soft tissue of the root of the nose between the thumb and the index finger of the nondominant hand. Then elevate the skin and muscle before placing the needle between the two fingers and injecting onabotulinumtoxinA into one or two sites in the center of the nasal radix (Fig. 3.26). The site of injection should be anywhere from 1 to 3 mm above or below the center of the nasion. The weaker muscle fibers of the procerus are injected with at least 4 U of onabotulinumtoxinA, while the stronger ones usually can be injected with up to 10 U and possibly even more in one, two, or more injection points. The depressor supercilii already will have been partially treated by the injections given at the medial aspect of the superciliary arch and eyebrows when the medial orbital orbicularis oculi is treated. Likewise, when the procerus is injected some diffusion of the onabotulinumtoxinA into the interdigitating fibers of the depressor supercilii and medial orbital orbicularis oculi will occur, particularly when gentle massage upward and laterally is performed to the right and left immediately after injection.

Some patterns of glabellar frowning are seen more frequently than others (20). The most common pattern forms observed by Trindade de Almeida were those produced by the simultaneous adduction and depression of the glabella (64%). This occurs when the corrugators contract and parallel vertical lines are formed in the center of the glabella as the skin of the brow moves toward the midline. At the same time, the procerus pulls the skin of the brow inferiorly, forming horizontal lines at the root of the nose. There are two distinct patterns when this happens. The less frequently observed pattern (27%) is what Trindade de Almeida calls the “U” pattern (Fig. 3.27A,B) (20). In these patients, the 5-point injection technique is corrective with 4 to 10 U of onabotulinumtoxinA given at each injection point (Fig. 3.27C) (20).

Stronger, more hyperkinectic corrugators and procerus produce similar glabellar frown lines but they are deeper and more acute, resulting in a pattern that better resembles a “V.” This was seen in 37% of the patients studied (Fig. 3.28A,B). Higher doses of onabotulinumtoxinA in the 7-point injection pattern are usually necessary to diminish these lines (Fig. 3.28A–D) (20).

Another, less frequently observed (10%) pattern of patients was one where, when they frown, the eyebrows initially adduct centrally and the glabella drops inferiorly. Then with continued frowning the upper part of the glabella will slide superiorly toward the frontal hairline and the mid-to-lateral end of the brow will move inferiorly to create an overall pattern that outlines the Greek letter omega (Fig. 3.29A,B) (20). In these individuals the corrugators and fibers of the medial brow depressors seem to contract in unison with the muscle fibers of the lower-to- mid-central frontalis. Inject 4 to 8 U or more of onabotulinumtoxinA at multiple sites into the corrugators and medial brow depressors, 0 to 4 U of onabotulinumtoxinA into the procerus and 4 to 6 U into the lower medial frontalis (Fig. 3.29A–D) (20).

There are those individuals whose predominant movement when frowning causes the center of the glabella to travel inferiorly along with the eyebrows. There are deep horizontal wrinkle lines across the nasal radix but minimal to no vertical glabellar lines (Fig. 3.30A,B) (20). In such individuals, treat the procerus with 6 to 10 U of onabotulinumtoxinA and the depressor supercilii and medial orbital orbicularis oculi with 4 to 6 U of onabotulinumtoxinA and the corrugators with 4 to 6 U of onabotulinumtoxinA. This “inverted omega” pattern was the least encountered (6%) and was attributed to individuals with a flat nasal radix and in Asians (Fig. 3.30A–D) (20).

Another less commonly seen glabellar frown pattern is the one where there is just adduction of the mid-to-lateral brow centrally with minimal production of horizontal glabellar lines or vertical movement of the glabella either inferiorly or superiorly. There seems to be a neutralizing balance of movements between the procerus and the frontalis that produces minimal or no horizontal glabellar frown lines in this “converging arrows” (or “parallel lines” author) pattern (20%) (Fig. 3.31A,B) (20). In these individuals mid-to-lateral brow corrugations can be seen more frequently depending on the person’s age and amount of skin laxity present (Fig. 3.24B). Inject 4 to 8 U or more of onabotulinumtoxinA into the belly of the corrugator supercilii (Fig. 3.31A,C). The medial horizontal fibers of the upper orbital orbicularis oculi may play a roll in the brow corrugations, which would require one or more intradermal injections of 4 to 6 U of onabotulinumtoxinA approximately 1 to 2 cm

above the supraorbital bony rim at the midpupillary line and medially along the superciliary arch (Fig. 3.31A–D). The procerus also can be treated with 4 to 6 U of onabotulinumtoxinA when indicated (author’s modification) (Fig. 3.24A).

Outcomes (Results) (see Appendix 3)

When proper injection techniques are followed, results are predictable and reproducible. The vertical lines between the eyebrows and the horizontal rhytides across the root of the nose will diminish and usually disappear. Glabellar and midbrow corrugations if treated appropriately also will be reduced and temporarily eliminated.

There can be a noticeably high arching of the eyebrows of approximately 2 to 3 mm, caused by the levator action of the frontalis in those patients whose glabellar depressors have been substantially weakened, but the interdigitating muscle fibers of the frontalis immediately above the brow have not (Fig. 3.32) (41–43). There also can be an increase in the distance between the eyebrows and an elevation of the medial aspect of the eyebrows when glabellar frown lines are treated with onabotulinumtoxinA because of the dynamic relationship between the brow depressors (corrugator, orbicularis oculi, procerus, depressor supercilii) and their brow levator (frontalis) (32,41–43). Accentuated high arching eyebrows may be attractive in most women, but usually

are not in men. In order to avoid a high arching brow in men, an additional 4 to 6 U of onabotulinumtoxinA can be injected intradermally 1.5 to 2.0 cm above the supraorbital margin at the midpupillary line (Figs. 3.19 and 3.20A–D) (6,44).

Usually, one can expect the effect of an onabotulinumtoxinA treatment of glabellar frown lines to last at least 3 to 4 months. Patients who are treated for the very first time with onabotulinumtoxinA may experience some asymmetry and therefore should return for an evaluation and possible touch-up injections within 2 to 3 weeks after a treatment. Frequently, the effects of onabotulinumtoxinA may last longer with each subsequent treatment session. Therefore, after the first 2 to 3 years of treatment sessions regularly scheduled every 3 to 5 months, some patients may prefer to return for their next retreatment on an as-needed basis (see Appendix 2).

Complications (Adverse Sequelae) (see Appendix 5)

Ptosis of the upper eyelid is the most significant complication seen when injecting onabotulinumtoxinA in and around the glabella (Fig. 3.33) (9,10). It is felt by some that blepharoptosis is caused by the migration of injected onabotulinumtoxinA through the orbital septum, weakening the levator palpebrae superioris (Fig. 3.34A,B).

Figure 3.33 Eyelid ptosis in this 49-year-old patient. Note a drop of 1–2 mm of the left upper eyelid that occurred approximately 10 days after an onabotulinumtoxinA treatment.

This is found to occur more frequently when large volumes of highly diluted onabotulinumtoxinA are injected deeply and low, close to the bony supraorbital margin at the midpupillary line. Occasionally at this location some actual muscle fibers of the levator palpebrae superioris extend anteriorly into the levator aponeurosis, allowing for easy access of the onabotulinumtoxinA that has diffused through the barrier of the orbital septum to weaken some of the muscle fibers of the upper eyelid levator, and produce ptosis of the upper eyelid (Fig. 3.15).

Blepharoptosis, when it occurs, is seen as a 1 to 2 mm or more drop in the upper eyelid, obscuring the upper border of the iris (Fig. 3.33). Ptosis can appear up to 7 to 10 days after an onabotulinumtoxinA injection and usually can last 2 to 4 weeks or even longer (4,6,9,10). An antidote for blepharoptosis is apraclonidine 0.5% eye drops (Iopidine®, Alcon Laboratories, Inc., Fort Worth, TX, USA). The ocular instillation of apraclonidine, an alpha-2-adrenergic agonist with mild alpha-1 activity, causes Mueller’s muscle (a nonstriated, smooth, sympathomimetic levator muscle of the upper eyelid) to contract, temporarily raising the upper eyelid approximately 1 to 2 mm (Figs. 3.15 and 3.34A,B). One or two drops should be instilled into the affected eye. If ptosis persists after 15 to 20 minutes, intraocular instillation of an additional one or two drops may be required before the affected eyelid will elevate. This procedure can be repeated three to four times a day. It is advisable to use apraclonidine eye drops only when absolutely necessary, because approximately 20% of patients can develop a contact conjunctivitis with frequent use. The mydriatic and vasoconstrictor phenylephrine (Neo-Synephrine® HCl, 2.5% ophthalmic solution, Sanofi Pharmaceuticals, Inc., New York, USA or Myfrin 2.5%, Alcon Laboratories, Inc., Fort Worth, TX, USA) is an alpha-1 agonist that also can be used when apraclonidine is not available (34). However, there are more potential side effects associated with the use of phenylephrine than with apraclonidine. Specifically, even when only the 2.5% ophthalmic solution is used, phenylephrine can acutely exacerbate narrow angle glaucoma, cardiac arrhythmias, and hypertension. Because it also is a mydriatic, even one drop of phenylephrine will prevent the patient from accommodating as usual and visual acuity can be compromised. Naphazoline (Naphcon-A®, Alcon Laboratories, Inc., Fort Worth, TX, USA or Vasocon-A®, Novartis Ophthalmics, East Hanover, NJ, USA) is another ophthalmic decongestant containing adrenergic properties that can be used to stimulate Mueller’s muscle to contract, temporarily lifting a ptotic upper eyelid (45). The different brands of Naphazoline also contain different antihistaminic additives, so they should be used infrequently, with caution and strictly on an as-needed basis when utilizing them just to reverse blepharoptosis.

Blepharoptosis also can be induced secondarily when the lower fibers of the frontalis are weakened, producing a drop in the height of the brow. The weight of the ptotic brow then impinges upon the upper eyelid and causes it to droop, narrowing the vertical palpebral aperture. This seems to occur more frequently in older patients who possess dermatochalasis of the skin of the eyelids and brow. In order to compensate for a heavy, lax brow, some individuals, regardless of age, involuntarily use the lower fibers of their frontalis to lift the soft tissue of the brow, which also maintains their upper eyelids in a raised position (21). When this compensatory action of the frontalis is weakened by onabotulinumtoxinA, a secondary blepharoptosis is created (45).

In younger patients with taut skin and no compensatory brow lifting, brow ptosis often can occur medially when there is an overzealous injection of onabotulinumtoxinA in the center of the forehead. Medial brow ptosis is exhibited by the medial head of the eyebrows appearing excessively lower than the lateral tail of the eyebrows. A bulge of skin in the center of the glabella also can accompany the “medial dip” of the eyebrows. This occurs because the lower central fibers of the frontalis are overly weakened and there is some activity of the fibers of the medial depressors, that is, the procerus, depressor supercilii, and medial orbital orbicularis oculi, pulling down on the center of the forehead and glabella (Fig. 3.35A,B).

Lagophthalmos or incomplete eyelid closure is another potential complication that can occur particularly when overzealous injections of

onabotulinumtoxinA are given in the periorbital area. Lagophthalmos results when there is a loss of the normal sphincteric function of the orbicularis oculi, and the upper eyelid does not close and approximate firmly against the lower eyelid. Loss of the sphincteric function of the orbicularis oculi either with involuntary blinking or with deliberate forced eye closure can occur when onabotulinumtoxinA diffuses into the palpebral portion of the orbicularis oculi, causing undue eyelid weakness. Lagophthalmos has been seen more frequently in patients treated for strabismus when extraocular muscles are treated with higher doses of onabotulinumtoxinA than when patients are treated for cosmetic reasons in the periocular area with the usual lower doses of onabotulinumtoxinA (46). On the other hand, patients who have an attenuated orbital septum because of age or other reasons may be more prone to this adverse sequela. If incomplete eyelid approximation is present for extended periods of time, exposure of the cornea can result in symptomatic dry eyes or exposure keratitis. There is no antidote for lagophthalmos, which can persist as long as the effects of the onabotulinumtoxinA are present. So protecting the patient from developing secondary dry eyes is extremely important, because excessive corneal exposure will lead to desiccation of the cornea and superficial punctate keratitis. Immediate consultation with an ophthalmologist at the first sign of lagophthalmos will prevent any additional eye injury.

Asymmetry is a minor adverse sequelae that sometimes is unavoidable, particularly when a patient is treated for the first time with

onabotulinumtoxinA (Fig. 3.36). There are three types of asymmetry that can be corrected with injections of onabotulinumtoxinA; iatrogenic; idiosyncratic; and incidental or acquired. An example of incidental or acquired asymmetry is Bell’s or facial (7th cranial) nerve palsy, or when one side of the face acquires a weakness because of an illness (e.g., cerebral vascular accident), or an accidental or traumatic injury. Idiosyncratic asymmetry occurs when a person is born with the inability to control or move a facial muscle to its fullest extent, while its

counterpart muscle on the contralateral side of the face is unaffected. This can result, for example, in one eyebrow or one eyelid being higher than the other (Figs. 3.36 and 3.37) or in a crooked, asymmetric smile (see chap. 5, pp. 154–160).

Many of those individuals who possess, unbeknownst to them, an idiosyncratic lower lying asymmetric brow on one side, commonly will also possess a lower lying upper eyelid on the same side (i.e., a secondary blepharoptosis) (Fig. 3.38A–C). With age, compensatory brow

lifting will raise the brows to maintain unobstructed vision (Fig. 3.39A). When the frontalis of these patients is treated with injections of onabotulinumtoxinA, the patient’s compensatory brow lifting can be interrupted. This diminution of compensatory brow lifting can occur even when only the upper fibers of the frontalis are weakened. The lower fibers of the frontalis do not necessarily have to be treated directly with injections of onabotulinumtoxinA to drop the brow a few millimeters. With a drop in brow height comes a concomitant drop in upper

eyelid height, and those patients who already have an asymmetrically lower upper eyelid on one side now appear to have developed blepharoptosis from the onabotulinumtoxinA injections (Fig. 3.39A–C). But in reality they more accurately have pseudoblepharoptosis, which is simply an unmasking of the ptosis they already possessed, probably because of an age related attenuation of the strength of the upper lid levator of that eye (Fig. 3.40A,B). When the patient first realizes that one upper eyelid is lower than the other, blame on the injector and the

onabotulinumtoxinA is a foregone conclusion (47). However, the astute physician will evaluate the patient carefully prior to any treatment and document the clinical findings with pretreatment photographs. This will enable the physician to discuss the actual problem with the patient and graphically demonstrate the presence of the compensatory brow lifting before embarking on a perilous course to treatment failure (Figs. 3.39A–C and 3.40A,B). So instead of the physician being led to believe that the patient developed blepharoptosis because

of a poor injection technique, the physician will be able to identify that the patient always had an idiosyncratic subclinical upper eyelid asymmetry that can be unmasked and even exaggerated with injections of onabotulinumtoxinA (Fig. 3.41A–C). This manifestation of pseudoblepharoptosis frequently occurs in patients over the age of 60 years who are treated for forehead wrinkles and glabellar frown lines with injections of onabotulinumtoxinA. Correction of pseudoblepharoptosis is not always totally successful but can be attempted by injecting

intradermally the lateral and medial pretarsal orbicularis oculi of the upper eyelid on the affected side with low doses of onabotulinumtoxinA (45,48).

The best way to avoid additional difficulties with patient rapport and confidence is to keep carefully documented written and photographic clinical notes (see Appendix 3). Discuss the physical findings with the patient and point out existing idiosyncratic asymmetries, anatomical differences, and potential adverse outcomes prior to treatment. Informing the patient of such findings before any treatment commences always is considered by the patient an accurate diagnosis of a unique situation. Explaining the circumstances and reasons for a particularly poor outcome after treatment always is considered by the patient an excuse for an improperly executed therapeutic procedure.

Iatrogenic asymmetry arises when an injection of onabotulinumtoxinA causes one side of the face to become weaker than the other (Fig. 3.42A). There are many reasons for this. The primary reason for one side of the face to become weaker than the other after an injection of onabotulinumtoxinA is when the stronger side is not injected with the equivalent dose of onabotulinumtoxinA as the contralateral side. This could be the

Figure 3.43 Note the erythema and edema in the pattern of the injections 10 minutes after a treatment of onabotulinumtoxinA of the forehead and glabella.

result of the onabotulinumtoxinA not diffusing as equally and completely through all the fibers of a muscle or group of muscles. Another reason could be that some of the fibers might have been physically resistant to the onabotulinumtoxinA, because those particular fibers were idiosyncratically thicker or stronger than the rest of the area and may have required a higher dose of onabotulinumtoxinA. Another possibility is that the injection was not given precisely symmetrically or in the thickest and strongest part of the muscle, causing a particular section of muscle to retain most or some of its strength. Iatrogenic asymmetry is probably the easiest to rectify. Generally with a few additional units of onabotulinumtoxinA injected into the appropriate area, iatrogenic asymmetry can be easily and expeditiously ameliorated (Fig. 3.42B).

Other untoward sequelae of more limited significance and duration can occur. These are the same adverse sequelae as those experienced with any type of subcutaneous or intramuscular injection. They include ecchymoses, edema, and erythema at the injection sites (Fig. 3.43), headache, and flu-like malaise. Rarely, if ever, do any of these side effects last beyond the day of the treatment, except for ecchymoses, which can last up to 10 days or more.

For some patients, a dull and transient headache with or without general body malaise occurs after injections of onabotulinumtoxinA that can last beyond 24 to 72 hours (49). The occurrence of headache immediately after an onabotulinumtoxinA injection seems paradoxical since onabotulinumtoxinA injections also are used to treat tension and migraine headaches by neurologists and other medical specialists. Headaches seem to occur more frequently in first time patients after their initial and subsequent treatment sessions. They stop occurring with repeat treatments, usually after the third, fourth, or fifth treatment session. Also, for the first-time recipient of a periorbital treatment of onabotulinumtoxinA, the presence of periorbital edema lasting a few hours to days may occur. This could be attributed to lymph stasis, possibly produced by a nondetectable attenuation of the sphincteric pumping action of the orbicularis oculi, reducing the efficiency of lymph fluid clearance from the surrounding soft tissue.

For some women, habitual scowling is the result of spending a lot of time outdoors, or suffering from constant and persistent headaches, or being plagued with poor vision and refusing to wear corrective eyeglasses, among many other things. Incessant contraction of the corrugator supercilii, manifested by habitual scowling, causes the medial end of the eyebrows to approach the midline. Many of these women will pluck and shorten the transverse length of their eyebrows by removing

eyebrow hair from the medial end of their brow. This will widen the glabellar interbrow space, so they do not look like they are habitually scowling, when they actually are (Fig. 3.44). After injections of onabotulinumtoxinA are given to reduce the number and extent of glabellar frown lines, the corrugators are no longer constantly contracting and adducting the eyebrows toward each other, narrowing the interbrow glabellar space. In fact, the transverse width of the glabella returns to its normal position because the corrugators are more relaxed at rest. However, those women who have plucked the medial portion of their eyebrows to visually widen a scowling brow before onabotulinumtoxinA, now complain after onabotulinumtoxinA that they look practically hyperteloric because their eyebrows are now widely separated. However, it is only because the medial aspects of their eyebrows have been excessively plucked that causes them to appear this way and not the injections of onabotulinumtoxinA. Such an adverse sequelae is difficult to predict, but warning prospective patients, who pluck their eyebrows, of such a side effect will prevent further disappointment on the part of the patient and additional frustration on the part of the physician. Also, beware of the patients who color in the shape of their eyebrows, because the shape that is chosen on the day of an onabotulinumtoxinA treatment may not necessarily correspond to the natural anatomical position of that person’s brow. Injections of onabotulinumtoxinA may return the area to its natural anatomic position, which paradoxically may appear to be distorting the glabellar area, when in reality it is not. Patients with permanent eyebrow tattooing may present with similar challenges and after treatment disappointments.

Serious reactions, particularly those of immediate hypersensitivity such as anaphylaxis, urticaria, soft tissue edema, and dyspnea have been extremely rare. When they occur, appropriate medical treatment must be instituted immediately (see Appendix 5).

Figures 3.45 to 3.53 are some examples of different patients treated with onabotulinumtoxinA for glabellar frown lines. Some also had treatment of their forehead frown lines during the same treatment session.

Treatment Implications When Injecting the Glabella

1.Accurate amounts of precisely placed injections of minimal volume onabotulinumtoxinA reduce the incidence of brow and eyelid ptosis.

2.Men may need higher doses of onabotulinumtoxinA than women for comparable results.

3.Women prefer arched eyebrows; men prefer straight, non-arched eyebrows.

4.When injecting the corrugator supercilii with onabotulinumtoxinA, remain medial to the midpupillary line and 1.5 to 2.0 cm above the supraorbital bony margin, and deep within the belly of the muscle.

5.Blepharoptosis can be transiently reversed with alpha-adrenergic agonist eye drops, but brow ptosis cannot be reduced and remits only when the effects of onabotulinumtoxinA diminish.

6.Preexisting asymmetry of the brow and eyelids should be identified and discussed with the patient before treatment, and might be corrected by accurately injecting appropriate doses of onabotulinumtoxinA on both the affected and non-affected side.

7.Patients with inelastic, redundant skin of the brow who have compensatory brow lifting because of a preexisting blepharoptosis can easily develop pseudoblepharoptosis when injections of onabotulinumtoxinA decompensate their brow lifting on the affected side.

HORIZONTAL FOREHEAD LINES

Introduction: Problem Assessment and Patient Selection

The easiest area of the face to treat with injections of onabotulinumtoxinA is the forehead (37). Many individuals contract their frontalis constantly for various and sundry reasons, and, in so doing, the skin buckles, creating parallel grooves and elevations across their foreheads. On the other hand, the presence of horizontal forehead lines seems to be directly proportional to one’s age or time spent in the sun. Older individuals generally have a number of forehead lines that become deeper with time. As one ages, the skin of the face, along with that of the rest of the body, typically becomes more inelastic and redundant. When this occurs in the upper face, a characteristic hooding of the brow over the upper eyelids also can result, which commonly is observed in the sixth or seventh decade in those individuals so predisposed. For these individuals a properly functioning frontalis is essential in maintaining a normal field of vision, because it is this muscle that will keep the brow from drooping and producing a hood of skin that drapes over the upper eyelids, interfering with their forward and upward gaze.

Younger patients who have horizontal forehead lines commonly attempt to conceal their obtrusiveness by wearing their frontal hair with a fringe or in bangs (Fig. 3.54A,B).

Generally, the presence of horizontal forehead lines causes one to appear stressed, worried, tired, or old. Abruptly raising the eyebrows by acutely contracting the frontalis also can express an emotion of surprise or even fear: emotions that one usually may not want to express too readily in certain situations (Fig. 3.55). When done properly, injections of onabotulinumtoxinA can diminish forehead wrinkling and replace one’s negative expressions with those that are more positive.

All too often it is the female rather than the male patient who is more concerned over the presence of forehead lines. Many of these women frequently are determined to eliminate any vestige of the appearance of a forehead wrinkle. A cautious and empathetic cosmetic physician will remind such patients that the absolute absence of forehead wrinkles, especially at full contracture or while expressing an emotion, may not be particularly appropriate for any reason. It portrays an individual as too artificial and stone-like in appearance, and thus should not be desirable. Because of the levator function of the frontalis, its interaction with the depressor muscles of the glabella and periorbital area, and the potential risk of overtreatment causing brow ptosis, there are many who believe treating the frontalis with onabotulinumtoxinA is not really as easy as one would expect (34).

Functional Anatomy (see Appendix 1)

The horizontal forehead lines are produced by the contraction of the muscle fibers of the frontalis, the only levator muscle of the upper third of the face (Fig. 3.56; see Fig. 2.2a,b). The function of the frontalis is to elevate the eyebrows, and the skin of the brow and forehead, and to oppose the depressor action of the muscles of the glabella and brow. It also retracts the scalp as a function of its participation in the occipitofrontalis galea aponeurotic complex.

The frontalis is a pair of quadrilaterally shaped, distinct muscles whose fibers are oriented vertically, producing the horizontal wrinkles of the forehead, which are perpendicular to the direction of muscle contraction. The frontalis lies beneath a thick layer of sebaceous skin and subcutaneous tissue and has no attachment to bone. The frontalis is indirectly connected to the occipitalis by the epicranial, membranous galea aponeurotica, which attaches to both muscles on either side of the scalp vertex, the occipitalis posteriorly and the frontalis anteriorly. The frontalis originates from the membranous galea aponeurotica superiorly and inserts into the subcutaneous tissue and skin of the brow at the level of the superciliary ridge (or arch) of the frontal bone. The fibers of the frontalis also interdigitate with muscle fibers of the brow depressors, that is, the procerus, corrugator supercilii, depressor supercilii, and orbicularis oculi. In some patients there can be a

Dosing: How to Correct the Problem (see Appendix 3) (What to Do and What Not to Do)

A typical dose for injecting the forehead in women is approximately 8 to 18 U of onabotulinumtoxinA. This can be injected either subcutaneously or intramuscularly at four to six sites across the forehead with 2 to 4 U of onabotulinumtoxinA placed in each site at intervals of 1.5 to 2 cm apart on either side of a deep crease (Fig. 3.58A) (51,52). For men, the typical dose is approximately 16 to 30 U of onabotulinumtoxinA and occasionally higher (51,53). This can be injected at 4 to 12 or even more sites either subcutaneously or intramuscularly depending on the height and width of the forehead, with up to 4 to 5 U of onabotulinumtoxinA placed in each site, depending on the strength of the frontalis (Fig. 3.58B) (3,53,54). Some patients, either men or women, can have many rows of fine forehead wrinkles, whereas others can have one or two rows of deeply set folds and furrows. The number and dosage of the onabotulinumtoxinA injections will depend on many factors, including the number and depth of the wrinkles, the size, shape, and strength of the muscle and the height, width, and shape of the forehead (Fig. 3.59) (34,37,55). More often than expected, and unbeknownst to the individual, a patient will present with asymmetrical eyebrows prior to their first treatment with onabotulinumtoxinA. Patients must be made aware of their idiosyncratic differences and their anatomic particulars must be documented both in the patient’s clinical chart and in their photographic record. Sometimes the eyebrows can be made symmetrically level with each other with carefully placed injections of onabotulinumtoxinA (Fig. 3.60A,B) and sometimes they cannot (Fig. 3.61A,B).

The patient usually is injected in an upright sitting or semireclined position. The pattern of injection across the forehead can vary. One can randomly inject 2 to 4 U of onabotulinumtoxinA subcutaneously or intramuscularly at any point on the forehead that is at least 2 to 2.5 finger breadths (i.e., 2–3.5 cm) above the superior

margin of the bony orbit (Fig. 3.62). One also can inject as much as 24 U of onabotulinumtoxinA or more subcutaneously across the forehead in a horizontal plane parallel to the wrinkles present (Figs. 3.63 and 3.64) (22). Another pattern that can be used is to inject 2 to 4 U of onabotulinumtoxinA subcutaneously in a wavy M configuration, whose arms diverge upward toward the lateral frontal hairline recession and then downward laterally (Figs. 3.62, 3.63, and 3.65A,B). This is accomplished by starting at a point in the midline approximately 2 to 4 cm above the medial aspect of the eyebrows, and injecting at three or four points moving upwardly and laterally in a diagonal pattern following the upward and downward arc of the eyebrows themselves. A distance of 2 to 3 cm should be maintained from the injection points and the upper border of the eyebrows, finishing inferior to the frontal hairline recession and 3 to 4 cm above the lateral aspect of the eyebrows, depending on the height of the forehead (Fig. 3.66A,B) (34). Injections in a pattern that is too high above the lateral tail of the eyebrows may result in unaffected fibers of the frontalis elevating the lateral eyebrow in the so-called “Mephisto” or “Mr. Spok” pattern (Fig. 3.67A–D). Otherwise, the simplest approach to treating the forehead is to inject onabotulinumtoxinA in a linear fashion across the forehead, maintaining the same distance above (approximately 2–3cm) and parallel to the eyebrows across the forehead with the highest point of injection being at the apex of an arched eyebrow (Fig. 3.68A,B). This pattern is best for women who have a relatively short rise to the height of their forehead (Figs. 3.63 and 3.66). This pattern will keep the onabotulinumtoxinA high enough above the eyebrows so they can form a peaked arch. Another technique is to inject subcutaneously approximately 2 to 4 U of onabotulinumtoxinA at sites approximately 2 cm apart and across the entire forehead horizontally at a point midway between the brow and the hairline also maintaining a constant distance above the eyebrows (Figs. 3.62, 3.63, and 3.66). This is advisable if the

X X X X

X

X X

X X

X X X

Figure 3.59 Random pattern injections into a forehead that is high and wide with multiple parallel wrinkles. This patient had 2 U of onabotulinumtoxinA injected at each site.

hairline is set low and if there are only one or two rows of horizontal wrinkles across the forehead (Fig. 3.63).

If the width of the forehead is narrow, that is, less than 12 cm between the anterior temporal lines, then four or five injections subcutaneously of 2 to 4 U of onabotulinumtoxinA at each injection site across the forehead are sufficient (Fig. 3.61A,B). One can feel the anterior temporal line by first identifying the zygomatic process of the frontal bone, which is the superior portion of the upper lateral wall of the bony orbit (Fig. 3.69). Its posterior edge continues upward, as a palpable protruding ridge along the lateral edge of the frontal bone, and arches upward and backward, delineating the anterior and superior boundary of the temporal fossa. If an individual has a wider brow, that is, more than 12 cm between the right and left anterior temporal lines, then five, six, or possibly more injection sites across the forehead are probably necessary, with 2 to 4 U of onabotulinumtoxinA injected at each site subcutaneously (Figs. 3.59, 3.64–3.66). The stronger the frontalis, the more units of onabotulinumtoxinA will be required to produce a desired effect.

Gentle massage upward and laterally at the injection sites for a few seconds helps to relieve the acute and transient pain of an injection and

X

Figure 3.69 Photo of skull illustrating the location and extent of anterior and superior temporal line. X, zygomatic process of the frontal bone; blue arrow, anterior temporal line; red arrow, superior temporal line.

can help disperse the toxin locally. Prolonged or heavy-handed massage can disperse the liquid onabotulinumtoxinA beyond the intended area of injection, weakening adjacent muscles fibers and producing unwanted results, for example, brow ptosis.

Outcomes (Results) (see Appendix 4)

An adequate result when treating the frontalis is to completely eliminate the horizontal lines of the forehead when the patient is at rest, but to provide the ability for some movement and minimal wrinkling when the patient is animated or actively expressing an emotion. Ideally, weakening of the frontalis should last at least 3 full months when a sufficient dose of onabotulinumtoxinA is injected. Frequently, after repeat treatments and occasionally after the first treatment session in some patients, the effects of onabotulinumtoxinA weakening can last as long as 4 to 6 months after onabotulinumtoxinA is injected (34). Overgenerous intramuscular injections of the frontalis with high doses of onabotulinumtoxinA will eliminate totally all movement of the muscle, even with forced contraction, creating a flat mask-like and motionless forehead and some degree of brow ptosis especially in patients (young or old) with inelastic skin. There usually is never a good aesthetic reason for such total denervation of the frontalis or any other muscle of facial expression even if it is only a temporary effect. In addition, the overall duration of results usually is not extended in any area when

onabotulinumtoxinA is injected at a higher dose than that which is normally adequate for the individual’s problem.

Occasionally and especially with the initial treatment of forehead wrinkles, the effect of onabotulinumtoxinA weakening may not occur symmetrically, and there may be wrinkling on one side of the forehead and not on the other, even at rest. It is imperative that the physician warn the patient of this before treatment and require the patient to return 2 to 3 weeks after a treatment session so that any minor asymmetries can be corrected. This is accomplished by injecting 1 to 2 U of onabotulinumtoxinA in the vicinity of the persistent asymmetric wrinkling and muscle hyperactivity (Fig. 3.67). Remember, this should always be done at least 2 to 3 cm above the eyebrow, so as not to produce brow ptosis inadvertently. This is particularly important for those patients who have multiple rows of low-lying horizontal forehead lines (Fig. 3.70A). By allowing the lower fibers of the frontalis to remain active, there typically may be a wrinkle or two immediately above the eyebrow and asymmetric brow elevation that might persist, because they cannot be reduced without causing brow ptosis (Fig. 3.70B,C). Most of the time, these narrow horizontal lines immediately adjacent to, if not within, the upper border of the eyebrow can be identified during the pretreatment physical examination and management planning (Figs. 3.67, 3.71A,B, and 3.72A–D). When low-lying horizontal forehead wrinkles occur, the patient should be made aware of their presence and given the option of other cosmetic procedures (e.g., fillers or resurfacing), before commencing with the injections of onabotulinumtoxinA. These minor horizontal forehead lines usually are the manifestation of excessively lax skin and a hyperactive frontalis being recruited to elevate a weighty brow to prevent brow hooding and visual field obstruction. One runs the risk of causing brow ptosis if total reduction of these lower forehead lines is attempted. Consequently, the patient is better off totally ignoring these lines. If they remain after treatment with onabotulinumtoxinA and still are extremely bothersome to the patient, they can be treated with a soft

tissue filler within 2 to 4 weeks or after the injections of onabotulinumtoxinA have completely taken effect.

Complications (Adverse Sequelae) (see Appendix 5)

When treating the frontalis with onabotulinumtoxinA, appropriate injection patterns and meticulous injection technique are extremely important in avoiding brow ptosis (44,56). This is best accomplished by remaining at least 2 to 3.5 cm above the supraorbital bony margin or 1.5 to 2.5 cm above the eyebrow depending on the idiosyncratic anatomy of the individual patient being treated. This will enable the muscle fibers of the frontalis to remain functional with adequate resting tone in the area directly above the brow so that the eyebrows will not droop and produce hooding over the upper eyelids (Figs. 3.67A–D and 3.73A,B).

In most patients, horizontal forehead lines are present in conjunction with glabellar frown lines. In these patients, it is imperative that the glabellar area is treated before or contemporaneously with the forehead; otherwise, because of the depressor action of the glabellar muscles, brow ptosis may be difficult to avoid. Maintaining an adequate resting tone of the lower fibers of the frontalis just over the brow (approximately 2–3cm) will help prevent brow ptosis by elevating the brow when the glabellar depressors are treated, because the resting tone of the glabellar depressors is slightly stronger than the resting tone of the brow levator, that is, frontalis (Fig. 3.74A,B). There is no antidote for brow ptosis, which can last as long as the onabotulinumtoxinA injection is effective. Injections of low-dose, low-volume onabotulinumtoxinA precisely placed in the superficial fibers of the lateral, upper, orbital orbicularis oculi may help to reduce the extent of brow ptosis (see below).

Clinical experience has indicated that when a more concentrated dose of onabotulinumtoxinA is used (i.e., dilutions of 1 ml per 100 U vial of onabotulinumtoxinA) there is minimal volume injected and migration of the onabotulinumtoxinA is negligible. The results also seem to last longer (56). On the other hand, to prevent total paralysis of muscle movement, especially with forced contraction of the frontalis, a different approach can be

utilized when attempting to aesthetically reduce horizontal forehead lines. Since there does not seem to be any agreement in the literature on which dilutions should be used when reconstituting a 100 U vial of onabotulinumtoxinA, or which dosage regimens are most effective, one then can inject the forehead with the same number of units of onabotulinumtoxinA, but with a more dilute solution (4,50,57). Namely, a 100 U vial of onabotulinumtoxinA can be reconstituted with 2 to 4 ml of saline when used solely for injecting the frontalis. This requires a greater volume to be injected. The toxin then can disperse over a wider area of the forehead, providing an effect that is less intensely paralyzing (48). However, injecting

large volumes of diluted onabotulinumtoxinA possibly might limit the duration of its effectiveness (6,57). As long as non-targeted muscle fibers (i.e.,those of the lower frontalis) are not directly in the wake of the intended toxin diffusion, this may be a more forgiving alternative injection technique, especially for the neophyte injector.

Other more common adverse sequelae that occur with an injection of onabotulinumtoxinA are related more to the actual physical injection rather than to the material injected. All of these adverse events are transient and generally do not last longer than 24 to 36 hours. They include ecchymoses, local edema, erythema, and pain at the injection

and adjacent sites (Fig. 3.43). For some patients, a dull and transient headache with or without general body malaise occurs after injections of onabotulinumtoxinA that can last beyond 24 to 72 hours (49). The occurrence of headache immediately after an onabotulinumtoxinA injection seems paradoxical since onabotulinumtoxinA injections are also used to treat tension and migraine headaches by neurologists and

other specialists. Serious reactions, particularly of the immediate hypersensitivity type such as anaphylaxis, urticaria, soft tissue edema, and dyspnea have been extremely rare. When they occur, appropriate medical treatment must be instituted immediately.

Figures 3.75 to 3.83 are additional examples of different patients treated with onabotulinumtoxinA for horizontal forehead lines.

PERIORBITAL AREA: LATERAL CANTHAL LINES

Introduction: Problem Assessment and Patient Selection

One of the first signs of aging is the wrinkles that radiate away from the lateral canthus outwardly and laterally, which are sometimes referred to as “crow’s feet” (Fig. 3.84). Depending on a person’s skin type, history of sun exposure, and muscle strength, crow’s feet can appear in someone as young as 20 years of age. The natural thinness and abundance of the skin in the lateral periorbital area make this site prone to wrinkling. These lateral canthal lines initially appear only during animation, they soon accentuate while smiling, laughing, or squinting and become increasingly noticeable with time. Their presence causes one to appear perpetually tired and fatigued and even older than one’s current age. For a woman, crow’s feet are the bane of her appearance, especially when make-up accumulates in the depths of the creases. For men, crow’s feet are a sign of hard work and fun in the sun.

When lateral canthal wrinkles are caused by the contraction of the lateral aspect of the orbital orbicularis oculi, they are referred to as dynamic wrinkles. They are the result of infolding and pleating of the overlying skin as the muscle contracts and they radiate away from the lateral canthus (Figs. 3.84 and 3.85). These wrinkles are perpendicular to the direction of the lateral muscle fibers of the orbital orbicularis oculi, which run mostly in a vertical direction around the lateral canthus (Fig. 3.85). These types of wrinkles can be diminished by injections of onabotulinumtoxinA (58–60). In some patients, however, age and photodamage are the

major contributing factors that produce lateral canthal wrinkles. These types of wrinkles are always present whether or not a person is actively animating and therefore are referred to as static wrinkles. When the bulk of crow’s feet are the result of static wrinkles, injections of onabotulinumtoxinA will be less effective. Only a resurfacing procedure or a soft tissue filler might help efface static wrinkling of the lateral canthus. When the bulk of crow’s feet are produced by the hyperactivity of the lateral orbital orbicularis oculi, then injections of onabotulinumtoxinA can play a significant role in diminishing the wrinkling (Fig. 3.86A,B).

Functional Anatomy (see Appendix 1)

The orbicularis oculi is a broad, flat, elliptical muscle. It encircles the globe and the periphery of the bony orbit. It is divided into three parts, the orbital, palpebral, and lacrimal parts (Fig. 3.87). The orbital part is the outermost portion of the muscle that forms a complete ellipse around the bony orbit. The orbital orbicularis oculi originates from the nasal component of the frontal bone, the frontal process of the maxilla, and the medial palpebral ligament. Its fibers form complete ellipses, without interruption even in its lateral aspect, where there is no bony attachment. In its superior aspect the orbital portion of the orbicularis oculi interdigitates with the muscle fibers of the frontalis, corrugator supercilii, depressor supercilii, and the procerus. It inserts into the soft tissue of the brow, anterior temple (superficial temporalis fascia), cheeks (interdigitating with fibers of the levator labii superioris

alaeque nasi, levator labii superioris, and zygomaticus minor), and medial and lateral canthal tendons. Contraction of the orbital orbicularis oculi approximates the upper with the lower eyelids, as with forced, volitional eyelid closure, and depresses the medial and lateral aspects of the eyebrows. Certain medial fibers of the orbital orbicularis

oculi have been referred to by some as the depressor supercilii. However, the depressor supercilii in recent anatomic studies has been identified as a distinct and separate pair of muscles, which insert into the undersurface of the skin at the medial aspect of the eyebrows. They pull the eyebrows downward when they contract (see Fig. 3.87) (36,37).

The fibers of the palpebral part of the orbicularis oculi arise from the medial palpebral ligament and from the bone on either side of the ligament. Its fibers are subdivided into pretarsal and preseptal portions (Fig. 3.88). The pretarsal portion courses over the eyelids and the preseptal portion lies superficial to the orbital septum at the junction between the bony orbit and eyelid. The preseptal fibers arise from the bifurcation of the medial palpebral ligament, while the upper and lower pretarsal fibers traverse laterally to join and form the lateral palpebral raphe.

Contraction of the palpebral orbicularis oculi provides the sphincteric action of the eyelids and gently closes them involuntarily, as occurs with blinking or sleep. The palpebral orbicularis oculi should not be treated with onabotulinumtoxinA for cosmetic purposes except in certain

situations and only by the most experienced injector because it can cause loss of the intentional and involuntary function of eyelid closure.

The lacrimal part of the orbicularis oculi is located posterior to the medial palpebral ligament and lacrimal sac (Fig. 3.89). Its fibers arise from the upper part of the lacrimal crest and travel posteriorly to the lacrimal sac and insert onto the upper and lower tarsal plates medial to the lacrimal puncta. Contraction of the lacrimal orbicularis oculi draws the eyelids and lacrimal papillae posteriorly against the globe, thereby placing the lacrimal puncta in direct contact with the lacrimal lake. Compression on the lacrimal sac dilates it, facilitating the lacrimal pump by creating negative back pressure within the canalicular system, and allowing tears to flow into the nasolacrimal duct.

Because crow’s feet are enhanced during smiling or laughing, the contraction of the risorius and zygomaticus major et minor also contribute to the formation of these lateral canthal rhytides. The zygomaticus major originates anterior to the zygomaticotemporal

suture line deep to the orbicularis oculi and travels diagonally toward the corner of the mouth (Fig. 3.90). It decussates with the modiolus and inserts into the skin and mucosa of the corners of the mouth. The zygomaticus major moves the angle of the mouth

superiorly, laterally, and posteriorly when a person laughs, smiles, or chews.

The zygomaticus minor originates from the zygomatic bone posterior to the zygomaticomaxillary suture line, just anterior to the origin of the

zygomaticus major, travels downward and forward and inserts into the mediolateral aspect of the upper lip (Fig. 3.90). The zygomaticus minor helps to create and elevate the nasolabial fold and to elevate the upper lateral aspect of the upper lip, producing the expression of disdain.

Figure 3.92 Crow’s feet accentuated by squinting or smiling in a person who is 64 years old.

The risorius is band like, usually poorly developed, and lies at the upper border of the facial platysma (Fig. 3.91). It does not originate from bone, but from the connective tissue and fascia overlying the parotid gland, platysma, masseter, and mastoid process. The risorius travels horizontally across the face, superficially to the platysma, decussates with the modiolus, and inserts into the skin of the oral commissure. The risorius at times can be indistinguishable from the platysma. The risorius can stretch the lower lip and displace the skin of the cheek posteriorly when laughing, grinning, or smiling—producing dimples in some individuals. Along with the platysma, the risorius can move the oral commissures in numerous facial movements in downward, upward, and lateral directions. Consequently, when a person laughs, smiles, or grins they contract the risorius and zygomaticus major et minor, which also can accentuate the lower aspect of their crow’s feet (Fig. 3.92).

Dilution (see Appendix 2)

When injecting onabotulinumtoxinA in the periorbital area, it is imperative that minimal volumes be precisely placed. This will necessitate reconstituting a 100 U vial of onabotulinumtoxinA with only 1 ml of normal saline. The recommended and approved method of reconstituting a 100 U vial of onabotulinumtoxinA with 2.5 ml of normal saline may not be the best dilution for accurate dosing when injecting precise amounts of onabotulinumtoxinA in areas of the face other than the glabella.

Dosing: How to Correct the Problem (see Appendix 3) (What to Do and What Not to Do)

When one performs injections of onabotulinumtoxinA or any other pharmaceutical in the periorbital area, both the patient and the physician should remain unencumbered, comfortable, and without

distractions. The patient should be in a sitting or semireclined position, approachable from both the left and right sides. When injecting onabotulinumtoxinA in the lateral canthal area, one should stand on the opposite side of the area to be treated with the patient facing toward the injector. This will allow the physician to approach the lateral canthus with the tip of the needle pointed lateral to and away from the patient’s eye. Stretching the skin over the target area with the nondominant hand under ample lighting enables the physician to visualize most of the blood vessels that lie just beneath the surface of the skin in this area (Fig. 3.93A).

Since the skin of the periorbital area is thin, the tip of the needle should be inserted no more deeply than 2 to 3 mm below the skin surface (14). Raising a wheal at each injection point will guarantee the injections were given at the proper depth (Fig. 3.93B,C). This will allow the onabotulinumtoxinA to diffuse slowly and evenly into the underlying muscle fibers of the lateral periorbita. While injecting onabotulinumtoxinA into the lateral canthus, it is important to remain at least 1 to 1.5 cm lateral to the lateral bony orbital rim. Approximately 2 to 4 U of onabotulinumtoxinA can be injected into each of two to four sites subcutaneously at the lateral orbital area 1.0 to 1.5 cm apart from each other for a total of 4 to 16 U of onabotulinumtoxinA on each side (Fig. 3.94A,B). Men may need slightly higher dosing, approximately 10 to 20 U per side for comparable results (Fig. 3.95A,B) (4).

Because there can be variable patterns of the lateral canthal lines from one person to the next, onabotulinumtoxinA treatments should be individualized for each patient. Generally, the lateral canthal lines can be identified as upper eyelid creases, lateral canthal creases, or lower eyelid or malar creases (Fig. 3.96). Characteristically, a patient can possess any one or multiple patterns of creases that can even be different in shape and severity from the left-to-right side of the face (Fig. 3.97) (62). Even though Kane identified four different patterns of crow’s feet, he concluded that the actual patterns manifested by patients were of no true anatomic significance. What mattered mostly was the recognition that there is a diversity in the motion of an individual’s orbicularis oculi creating different crow’s feet patterns and consequently they should be treated with varying doses of onabotulinumtoxinA accordingly. In addition, a person may have a certain percentage of either static or dynamic wrinkles, but only the dynamic ones are reducible by injections of onabotulinumtoxinA. The number of injection sites and the amount of onabotulinumtoxinA injected will depend on the pattern, depth, and severity of the lateral canthal wrinkling as well as the thickness of the skin and the presence or absence of blood vessels (Fig. 3.97) (53,59–66). Men, generally, will be satisfied with less of a reduction in wrinkling of the lateral canthi, especially with active movements such as smiling and laughing.

In order to avoid puncturing any one of the many superficial vessels found in and around the lateral canthus, the total dose of onabotulinumtoxinA can be injected intradermally or subcutaneously as a single bolus at one or two sites, producing one or two wheals on the surface of the skin (Fig. 3.98) (10). The wheals of onabotulinumtoxinA are then gently massaged laterally and away from the orbital fossa in an upward and downward direction. By carefully kneading a bolus of onabotulinumtoxinA around the lateral canthus, the injected onabotulinumtoxinA is dispersed subcutaneously and over the muscle fibers of the lateral orbital orbicularis oculi. This maneuver can prevent postinjection ecchymoses if none of the periorbital vessels are punctured. The bolus of onabotulinumtoxinA is always injected 1 to 1.5 cm lateral to the lateral bony orbital margin.

When treating crow’s feet, especially at the level of the lower eyelid and lateral malar prominence, it is extremely important to inject onabotulinumtoxinA in the intradermal or superficial subcutaneous plane, where the superficial muscle fibers of the orbital orbicularis oculi insert (14).

The duration of effect of onabotulinumtoxinA treatments of the lateral canthus usually is somewhat shorter than that seen in other areas of the face. At least 3 months and sometimes up to 4 months of diminished crow’s feet can be obtained with proper dosing and accurate placement of the injections. For some patients the duration of effect is extended with subsequent treatments of onabotulinumtoxinA (59,60).

Outcome (Results)

If the treated crow’s feet are dynamic and the result of contractions of the orbital orbicularis oculi, there will be a significant improvement to the area (Fig. 3.99A–D). However, if the crow’s feet are mostly static and the result of photodamage and chronological aging, then the improvement will be disappointing, especially if the patient was not warned of this prior to treatment. It is important always to assess and

discuss a particular problem and its solution in detail with the patient before initiating a course of treatment with onabotulinumtoxinA. It is also in the best interest of both patient and physician to document the pretreatment consultation both in writing and with photographs (see Appendix 3). The documentation should include any remarks the patient may have voiced during the interview. All too often, a patient’s memory of a physician’s concerns and predictions prior to treatment are easily forgotten by the patient after treatment.

Most of the time, the best way to diminish lateral canthal static wrinkling is by some form of ablative resurfacing, whether by laser ablation, dermabrasion, or chemical peeling and the addition of a soft tissue filler when appropriate (62). The different types of non-ablative facial rejuvenation techniques still have not been able to eliminate completely the deep and dense solar elastotic changes that create the pronounced crow’s feet in the manner in which many patients over 50 years of age would like. In such cases, oftentimes a treatment regimen of regularly scheduled onabotulinumtoxinA injections after an ablative resurfacing procedure that is periodically augmented by injections of a soft tissue fillers is the only way many patients will be able to realize the kind of facial improvement they are seeking (Fig. 3.100) (43,66). Prolongation of such improvements then can be accomplished regularly, albeit infrequently throughout the year, with non-ablative laser, intense pulsed light, or similar types of superficial facial rejuvenation treatments and the daily application of topical retinoids, alpha hydroxy acids, or similar cosmeceuticals.

When the lateral orbital orbicularis oculi is exceptionally hyperfunctional, causing deep and elongated crow’s feet that are recalcitrant and resist improvement with injections of onabotulinumtoxinA placed in the usual sites, additional injections placed posteriorly toward the lateral limits of the orbicularis oculi in the temporal area can be beneficial (Fig. 3.101A–D) (67).

Be cautious when treating the lower malar type of lateral canthal lines, because the majority of these lines may be produced by a hyperkinetic zygomaticus major. If the patient possesses redundant skin around the lateral canthus, then injecting onabotulinumtoxinA into the lower crow’s feet area can create additional skin folding over

the lateral malar prominence and exacerbate diagonal wrinkling of the mid and lateral cheeks. The propensity for this may be identified prior to treating the patient with onabotulinumtoxinA by having the patient smile forcibly and repeatedly. If their lower lateral canthal lines are continuous with diagonal wrinkles of the mid and lateral cheeks, caution must be taken when injecting the lower malar crow’s feet (Figs. 3.92 and 3.102). Soft tissue fillers or resurfacing may be the best way to rid the patient of these particular types of rhytides (Fig. 3.100). Treating the zygomaticus major with onabotulinumtoxinA can easily result in an asymmetric smile and upper lip incompetence (see Complications below).

Complications (Adverse Sequelae) (see Appendix 5)

When injecting the lateral orbital orbicularis oculi, onabotulinumtoxinA should be placed intradermally or subdermally. The injections should not be placed any more medially to an imaginary vertical line that passes through the lateral canthus, nor below the level of the superior margin of the zygomatic arch. Otherwise, the muscle fibers of some of the levators of the lateral upper lip and corners of the mouth will be affected by the diffusion of the onabotulinumtoxinA, and result in lateral upper lip ptosis and possibly oral sphincter incompetence (67,68). This can occur because the zygomaticus major et minor originate at or near the lateral aspect of the superior margin of the zygomatic arch (Fig. 3.92). If the zygomaticus major or minor is injected with onabotulinumtoxinA, the lateral aspect of the ipsilateral upper lip will be weakened, causing a drooping of the upper oral commissure, an asymmetric smile, and possible drooling and incontinence of food and liquid. If onabotulinumtoxinA is injected or even diffuses more medially and inferiorly to the superior margin of the zygomatic arch, then the central and deep lip levators (levator labii superioris, levator labii superioris alaeque nasi, and levator anguli oris) can be affected, causing a more profound interference with upper lip competence and basic sphincteric functions, resulting in dysarthria and dysphagia.

Injecting subcutaneously small volumes of concentrated onabotulinumtoxinA far enough (i.e., 1.0–1.5 cm) away from the lateral side wall of the bony orbit will prevent the unintended migration of

onabotulinumtoxinA medially and into the superior or inferior, or both, palpebral orbicularis oculi. If this occurs, weakening of the lateral canthal tendon occurs, producing lower eyelid ectropion, which manifests as rounding of the lateral canthus (Fig. 3.103). Rounding can lead

to secondary complications initially manifesting as epiphora (tearing) or even possibly prolonged corneal exposure, and secondary xerophthalmia (dry eye), which eventually can result in corneal damage (superficial punctate keratitis) (10,54). Because of their position within

the orbit, the lateral and inferior rectus, or inferior oblique are especially disposed to accidental diffusion of injected onabotulinumtoxinA through the orbital septum. If any of the extraocular muscles are inadvertently weakened by onabotulinumtoxinA, diplopia and strabismus will result. If any of these serious complications does occur, immediate consultation with an ophthalmologist is imperative (54).

Overzealous treatments of onabotulinumtoxinA in the lateral periorbita that are either forcibly injected or given with high doses of high

volume onabotulinumtoxinA also can result in brow ptosis, ectropion, diplopia, xerophthalmia, lagophthalmos, and even superficial punctate keratitis because of corneal exposure. Brow ptosis is caused by the diffusion of onabotulinumtoxinA into the lower fibers of the frontalis when onabotulinumtoxinA is injected rapidly, or the area is massaged vigorously after injection (Fig. 3.104A–D). Patients can cause brow ptosis if they manipulate the injected area excessively, enough to disperse the onabotulinumtoxinA beyond the targeted area immediately

after a treatment session. Injecting large volumes of low concentrations of onabotulinumtoxinA also increases the risk of dispersion beyond the targeted muscle. Ectropion occurs when the muscular sling of the lateral orbicularis is inadvertently weakened by injections of onabotulinumtoxinA, especially in someone who has had an interventional eyelid procedure, namely, blepharoplasty, deep chemical or laser resurfacing, etc. This is generally seen as excessive rounding of the contour of the lateral canthus (Fig. 3.103).

In rare instances, when the lateral orbital orbicularis oculi is weakened with onabotulinumtoxinA and the lower crow’s feet are eliminated, a flattening of this periocular area can result. When the lateral upper lip levators (zygomatic major and minor) are still functioning normally and the patient smiles emphatically, there may appear a peculiarly abrupt change in contour from the fully rounded, finely corrugated midand lateral cheek to the flattened wrinkleless periocular area (38). For these patients a soft tissue filler in the lateral malar deficit is the best way to temporarily correct the problem (Fig. 3.105). Kane attributes this phenomenon to the fact that the orbicularis oculi is an accessory upper cheek levator (62). He also feels that when the lower lateral orbicularis oculi is completely denervated with injections of onabotulinumtoxinA, there is a loss of upper cheek elevation and lax skin will become redundant just inferior to the lower eyelid when a person smiles. In younger patients who still have tight and elastic periorbital skin, the excess lower eyelid skin folding and wrinkling does not always occur. There is just an abrupt contour difference between the lower lateral periorbita and the upper zygoma. However,

in older patients with loose, inelastic skin, a full smile may create an unnatural expression after injections of onabotulinumtoxinA because this area does not contract as it normally should. Especially when there is a complete elimination of periorbital wrinkling after an onabotulinumtoxinA treatment, the lateral eyebrow is often left unnaturally elevated. Consequently, when such a patient smiles, there is a flattening of the normally occurring upper cheek bulge, because some of the natural cheek elevation is lost. Also, in severe cases, even at rest, there is an extra roll of skin, which becomes embarrassingly apparent at the junction of the lower eyelid and cheek skin. When this lateral portion of the muscle functions normally, it elevates the lateral eyelid skin and redistributes some of the excess skin of the lower eyelid. When the orbicularis oculi is completely denervated by onabotulinumtoxinA, this no longer occurs and the redundant lower eyelid skin forms a visible roll or folds of the skin (Fig. 3.105) (62).

The incidence of the usual transient adverse sequelae that accompany a transcutaneous injection, including pain, erythema, edema, and ecchymoses can be mitigated with the use of ice and the application of a local topical anesthetic. The anatomy of the periocular area, however, makes occluding the topical anesthetic somewhat difficult and impractical. The patient also should be reminded to stop alcohol, aspirin, nonsteroidal anti-inflammatory drugs, anticoagulants, and other medications, and food supplements that increase coagulation time at least two weeks prior to treatment.

Figures 3.106–3.110 are some examples of different patients treated with onabotulinumtoxinA for crow’s feet (lateral canthal lines).

Treatment Implications When Injecting the Lateral Orbicularis

Oculi (Crow’s Feet)

1.All periocular injections of onabotulinumtoxinA should be placed in the lower dermis or superficial subcutaneous tissue and not any more deeply.

2.Inject onabotulinumtoxinA slowly placing the needle 1.0 to 1.5 cm lateral to the bony orbital rim and directing it away from the globe into the lateral canthus to avoid diplopia and injury to the eye.

3.Older patients will have varying degrees of improvement after a treatment of onabotulinumtoxinA, depending on the amount of photoaging, redundant skin, and static wrinkling present.

4.Posttreatment ecchymoses can last over one week, fallaciously suggesting incompetence and a substandard injection technique by the injector. Stop aspirin, NSAIDs, anticoagulants and other medications, and all home remedies that increase coagulation time at least two weeks before a treatment session. The application of ice before and moderate point pressure to the skin after an injection can reduce the extent of ecchymoses.

5.Upper lateral canthal injections of the orbital orbicularis oculi also can be used to produce a lateral eyebrow lift when used in conjunction with onabotulinumtoxinA injections of the glabellar and forehead muscles (see next section).

6.Injecting the lower lateral canthus with large volumes of onabotulinumtoxinA can produce upper lip asymmetry and cheek ptosis if the upper lip levators are inadvertently treated. Therefore, inject onabotulinumtoxinA well above the superior margin of the zygoma and remain 1.0 to 1.5 cm from the bony orbital rim.

7.Accurately dosed and precisely placed low-volume onabotulinumtoxinA injections are essential in order to avoid adverse sequelae in the periorbital area.

PERIORBITAL AREA: LATERAL EYEBROW LIFT

Introduction: Problem Assessment and Patient Selection

With the progression of time and the accumulation of hours spent outdoors, the skin of the face as well as the rest of the body becomes more inelastic, causing it to sag and drape more loosely. This can

appear as hooding of the lateral brow with the uniquely characteristic appearance of ptosis of the lateral eyebrow (Fig. 3.111). The thick skin of the lateral brow, when it becomes ptotic, gives the bearer a “heavy” down trodden look. It makes one appear tired, overburdened, and preoccupied with worries and concerns. High, arched lateral eyebrows convey an expression of happiness, vigor, approval, confidence, and sensuality. Depressed, low positioned or flat lateral eyebrows convey an expression of sadness, fatigue, anxiety, disdain, and disapproval. With advancing age, many individuals become ideal candidates for upper eyelid blepharoplasties and brow lifts. The physical appearance of this hooding generally affects men at a later age than women, but men as well as women with this problem eventually will benefit from an upper eyelid blepharoplasty, brow lift or both when the hooding progresses and peripheral vision is impeded. In the meantime, chemodenervation with onabotulinumtoxinA will forestall the inevitable by elevating the lateral brow and providing one with many more years of a more youthful, less tired appearance.

Functional Anatomy (see Appendix 1)

The reason for lateral brow ptosis is multifactorial. As the skin and supportive soft tissues of the periorbita become inelastic and redundant, the lower lateral fibers of the frontalis become less efficient in elevating the heavy mass of periorbital skin above the lateral orbital bony rim. In addition, the antagonistic muscle movements of repeated frowning and the strong contractions (i.e., depressor action) of both the lateral aspect of the horizontal fibers of the upper orbital orbicularis oculi and the vertical fibers of the lateral orbital orbicularis oculi, in conjunction with the ineffective levator action of the lateral frontalis, progressively produce a downward drooping of the lateral eyebrow (Fig. 3.112).

Dilution (see Appendix 2)

Treating the periocular area should be done with low volume, highly concentrated onabotulinumtoxinA. Therefore, reconstituting a 100 U vial of onabotulinumtoxinA with 1 ml of normal saline is best for precise injections with accurate dosing when a 3/10 ml BecktonDickenson U-100 insulin syringe with a 31-gauge needle is used.

Dosing: How to Correct the Problem (What to Do and What Not to Do)

To elevate and enhance the arching of the lateral eyebrow, especially in women, 2 to 4 U of onabotulinumtoxinA can be injected intradermally or subdermally into the lateral depressor, that is, the lateral orbital orbicularis oculi, in the vicinity of maximal contraction. This often is seen clinically as corrugations in and around the tail of the eyebrow (Fig. 3.113). They correspond to where the lateral aspect of the superciliary arch meets the lower aspect of the anterior temporal line at the zygomatic process of the frontal bone (Figs. 3.69 and 3.114). Depending on the idiosyncratic anatomy of the patient being treated, intradermal injections can be placed just above or below the hairs of the lateral aspect (i.e., tail) of the eyebrow (Fig. 3.115A,B). One or multiple (usually no more than three) injections of 2 to 4 U of onabotulinumtoxinA can be given intradermally in this area of

maximal muscle contraction. Higher doses can be used with a lesser number of injection points. Injecting onabotulinumtoxinA in this area reduces the depressor action of the horizontal and vertical muscle fibers of the orbital orbicularis oculi at the lateral aspect of the brow, and allows the muscle fibers of the lower lateral aspect of the frontalis to elevate the lateral eyebrow (Fig. 3.116A–D) (51–53,69,70).

With the patient in the sitting or semireclined position, have the patient forcibly elevate and depress the eyebrows. This will allow one to assess the depressor strength of the lateral orbicularis oculi and the levator strength of the lateral frontalis. After determining the dose of onabotulinumtoxinA needed, have the patient once again forcibly elevate the eyebrows. Facilitate and maintain the upward movement by supporting the skin with the thumb and index finger of the nondominant hand. This maneuver allows the lower muscle fibers of the frontalis

to rise up, thereby uncovering and exposing the superficial muscle fibers of the upper orbital orbicularis oculi. With the bore of the needle pointing upward and away from the orbit inject intradermally approximately 2 U to no more than a total of 8 U of onabotulinumtoxinA into one and usually no more than three injection sites along the lateral brow. Start the injections from the lateral aspect of the eyebrow and place them 1 cm apart from each other and finish at a point just lateral to the midpupillary line along the superciliary arch in patients with a strong orbicularis oculi who display lateral brow depression with or without hooding or corrugation (Fig. 3.117). OnabotulinumtoxinA must be injected slowly and intradermally and no more deeply than subdermally

into the superficial subcutaneous tissue of each lateral brow. Raising a wheal at each injection point will guarantee the injection was given at the proper depth of the intradermal/subcutaneous interface (Fig. 3.118). Ordinarily, one to three intradermal injections of 2 to 3 U of onabotulinumtoxinA placed into the lateral aspect of the brow will suffice to produce an aesthetically pleasing lateral brow lift and a diminution of idiosyncratic lateral brow corrugations (Figs. 3.119A–D and 3.120A–D). This superficial injection technique will reduce the risk of the onabotulinumtoxinA dispersing beyond the intended area and producing adverse sequelae, that is, brow and eyelid ptosis, ectropion, strabismus, diplopia, or xerophthalmia (see Appendix 5).

Outcomes (Results) (see Appendix 4)

Lateral brow elevation is best appreciated as a decrease in hooding of the lateral aspect of the upper eyelid (Figs. 3.120 and 3.121) (51–53,68–71). Elevating the eyebrows at their medial, central, or lateral aspects can be unpredictable when first attempted, but usually reproducible when the proper technique is used and appropriate, specific clinical records and sequential photographs are kept

(see Appendix 3) (53,68–71). With the proper technique the complication rate is low and for some individuals the results might be subtle at best (65). Therefore, each patient’s clinical record must include diagrammatic as well as photographic documentation along with written or typed progress notes if reproducible results are expected. The desirability of lifting the eyebrows for one patient or another—that is, the medial, central, or lateral aspect—will

depend on current fashion trends and standards. The preference for lifting the eyebrows will depend on the patient’s overall physiognomy and idiosyncratic anatomy. The feasibility for doing so will depend on whether or not the physician is capable of injecting onabotulinumtoxinA with a reproducible technique. Typically, the effects of onabotulinumtoxinA in the area of the lateral brow last as long as those of the glabella.

It is important to identify and remind each patient that attempting to eliminate the horizontal forehead lines that are positioned immediately above and adjacent to or within the lateral eyebrows are impossible to eliminate without causing lateral brow ptosis (Figs. 3.71A,B and 3.72A–D). Those lines exist because they identify a person with inherent brow ptosis and compensatory brow lifting (Fig. 3.39A–C). It is the presence of functioning lower fibers of the lateral frontalis that is needed to raise the lateral brow. When there is excessive skin laxity (i.e., dermatochalasis) in the area of the lower lateral forehead and lateral brow, the skin redundancy, creating lateral orbital hooding and horizontal wrinkles immediately above the lateral brow may or may not be treatable by onabotulinumtoxinA to the patient’s satisfaction (Fig. 3.122).

Complications (Adverse Sequelae) (See Appendix 5)

It is important to keep in mind that when treating the forehead with onabotulinumtoxinA, injections in the lateral aspect of the frontalis

should not be done too high or too low. Injections that are too high can result in the excessively elevated lateral eyebrow, producing what is known as the Mephisto or “Mr. Spock” look. Injections that are too low will cause or accentuate brow ptosis and will negate any further attempt at lateral brow elevation until the strength of the lower lateral frontalis muscle fibers returns.

Xerophthalmia or dry eye can occur if onabotulinumtoxinA is injected too deeply in the upper lateral aspect of the periorbital area and it diffuses into the lacrimal gland and diminishes its secretion. When this occurs, regular and constant instillation of some form of commercially available artificial tears (i.e., ophthalmic normal saline) will be necessary until the lacrimal glands begin to function again. Consultation with an ophthalmologist also is recommended.

Forceful, deep, and rapid injections at the lateral canthus can cause the onabotulinumtoxinA to diffuse into the bony orbit and weaken the lateral extraocular muscles, causing strabismus and diplopia. The best way to avoid these complications and other adverse sequelae is to inject onabotulinumtoxinA slowly and intradermally with 2 to 3 U per injection point in women and 3 to 4 U per injection point in men. The dosage will depend on the strength of the frontalis and presence or absence of dermatochalasis and lateral orbital hooding.

Figures 3.123–3.129 are some examples of different patients treated with onabotulinumtoxinA to elevate the lateral brow.

Treatment Implications when injecting the Lateral Eyebrows

1.Injecting 4 to 6 U of onabotulinumtoxinA in the upper lateral eyebrow temporarily produces a lateral brow lift, increases the vertical palpebral aperture, and corrects lateral canthal hooding in older patients.

2.Injections must be performed intradermally over the tail of the eyebrow; otherwise, the lacrimal gland will be affected and xerophthalmia may occur. Raising a wheal confirms a superficial injection.

3.Before injecting onabotulinumtoxinA intradermally, have patients raise their eyebrows elevating the lower fibers of the frontalis to uncover the upper fibers of the orbital orbicularis oculi in the vicinity of the lateral eyebrows.

4.Accurate dosing and precise superficial injection technique will avoid diffusion of onabotulinumtoxinA into the lower frontalis and the exacerbation of lateral orbital hooding.

5.Upper lateral orbicularis oculi injections placed intradermally and along the superciliary arch but lateral to the mid papillary line will diminish the skin corrugations of the lateral brow seen in some patients.

6.Maintaining the strength of the lower lateral fibers of the frontalis and prevent worsening of lateral orbital hooding by injecting onabotulinumtoxinA intradermally and 1.5 to 2.5 cm above the bony orbital rim along the superciliary arch. Prevent a Mephisto or “Mr. Spock” look by injecting onabotulinumtoxinA intramuscularly into the lowers fibers of the frontalis, 2.5 to 3.5cm above the lateral bony orbit.

7.In patients with excessive skin laxity (dermatochalasis) in the lateral brow and lower forehead, injections of onabotulinumtoxinA may not satisfactorily lift the lateral brow and relieve brow hooding.

PERIORBITAL AREA: LOWER EYELID LINES

Introduction: Problem Assessment and Patient Selection

Along with crow’s feet and lateral brow ptosis, many people have additional folds and creases of the lower eyelids, which give them the appearance of being tired, sleep deprived, or even older than their current age. These “festoons” or “jelly rolls” are produced by a hyperkinetic palpebral (preseptal portion of the) orbicularis oculi and some degree of skin laxity and blepharochalasis (Fig. 3.130A,B). They also help

create the appearance of “dark circles” and baggy eyes that women and even men would prefer not to have. Likewise, a tired, disinterested, downtrodden, and unambitious demeanor is projected when the palpebral aperture is narrowed because of a hyperfunctional pretarsal orbicularis oculi. Various facial movements, primarily smiling or laughing, also will narrow momentarily the palpebral aperture. Injections of onabotulinumtoxinA in the lower palpebral orbicularis oculi will reduce excess wrinkling, widen the ocular aperture, and produce a more youthful, happy, and overall pleasant appearance.

Functional Anatomy (see Appendix 1)

The orbicularis oculi helps protect the eyes from bright light, gusts of air, and fast flying projectiles. Those working outdoors or in a brightly lit environment automatically maintain their orbicularis oculi in a constant hyperkinetic state of partial closure, that is, they are continuously squinting. This can cause the muscle fibers of the orbicularis oculi to hypertrophy. In younger patients, hypertrophic palpebral orbicularis oculi can be observed as producing additional periocular folds, and are sometimes referred to as ‘jelly rolls,’ especially in the vicinity of the lower eyelid (Fig. 3.130A,B). These lower eyelid folds can be diminished by onabotulinumtoxinA (Fig. 3.131A–D). In older patients, however, the skin of the eyelids becomes thin, redundant, and inelastic. The orbital septum attenuates, becoming less effective. Because of a weakening of this anatomical bulwark, the inferior periorbital fat bulges from behind the preseptal orbicularis oculi and creates characteristic suborbital “festoons” (Fig. 3.132A,B). OnabotulinumtoxinA injections of the already weakened and incompetent preseptal orbicularis oculi invariably will enlarge this type of suborbital festooning, and therefore should not be performed (64).

A major function of the palpebral portion of the orbicularis oculi is its sphincteric blinking action, which aids in the maintenance of corneal moisture. It accomplishes this with each blink of the eye, which distributes over the anterior surface of the globe the drops of tears that are secreted from the main and accessory lacrimal glands (Fig. 3.133). Opening and shutting the eyes activates the so-called lacrimal pump, shunting the secreted tears through the canalicular system into the lacrimal sac and down the nasolacrimal duct, where the accumulated fluid from the tears is then released into the nasal cavity from the inferior meatus under the inferior nasal turbinate. As the secreted tears flow from the lacrimal glands in the upper lateral aspect of the orbit, they collect in the lower medial corner of the orbit to form the lacrimal lake. With the eyelids open, the lacrimal portion of the orbicularis oculi compresses the lacrimal sac and positions the

patulous punctum in direct contact with the globe and the lacrimal lake. This allows the tears to flow into and through the patent canaliculi. Contracting the superficial fibers of the pretarsal orbicularis oculi shuts the eyelids and distributes the tears over the anterior surface of the globe from a superior lateral to an inferior medial direction. Opening the eyes again causes the deep fibers of the pretarsal orbicularis oculi to contract, shutting down the upper and lower canalicular system. Contemporaneously, the deep fibers of the preseptal orbicularis oculi pull on the lateral walls of the lacrimal sac,

enlarging its lumen and contributing to the negative pressure gradient within the nasolacrimal canalicular system, which causes the tears to be aspirated into the lacrimal sac (Fig. 3.133). Upon reopening the eyelids, the positive pressure within the canalicular system is recreated and the lacrimal sac collapses, propelling the tears into the nasolacrimal duct, then through the inferior meatus and into the nasal cavity. Simultaneously, the puncta and canaliculi reopen to collect more tears from the lacrimal lake and the process recycles with each opening and shutting of the eyelids.