Ординатура / Офтальмология / Английские материалы / Atlas of Aesthetic Eyelid and Periocular Surgery_Spinelli, Lewis, Elahi_2004
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A T L A S O F A E S T H E T I C E Y E L I D A N D P E R I O C U L A R S U R G E R Y
closer monitoring, the tarsorrhaphy may be made reusable and the lids may be opened, the globe assessed, and the lids reclosed and suspended with tape. Tarsorrhaphy provides excellent corneal coverage and comfort for these patients, who inevitably have some
form of intraoperative corneal de-epithelialization during surgery. It also allows a maximal recession of the lower lid retractors, which are lysed during the transconjunctival approach to the orbital floor (Figs. 11-1 and 11-2).
ORBITAL VOLUME REDUCTION
A Soft tissue dissection
Displaced zygoma fracture causes enophthalmos
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Fractured |
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orbital floor |
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B Fracture is recreated |
Displaced |
to mobilize zygoma fragment |
zygoma fracture |
CZygoma fragment is repositioned with
a bone graft bridging
the gap in the zygomatic arch 
Preoperative zygoma position
Figure 11-1 The orbital volume discrepancy between bone and soft tissue contained within is common after an unreduced zygoma fracture. The presenting soft tissue deformities, including enophthalmos, superior sulcus depression, lateral canthal dystopia, scleral show, and pseudoptosis, are all tempting to address with soft tissue procedures alone. A, In all but the mildest cases the surgeon should always consider repositioning the displaced bone first, before considering soft tissue “masking” procedures. The zygoma and orbit can be degloved with a coronal (hemi), vestibulobuccal, and transconjunctival incision. The inferior crus of the lateral canthal tendon can be divided, giving complete access to the orbital floor with the risk of traction tears. Every attempt should be made to remain preseptal and then subperiosteal in a continuous plane with this dissection (arrow). Although exaggerated here, the orbital floor is already healed with fibrous and/or bony union in a displaced position. B, Osteotomies are then performed using a power microsaw of personal preference (sagittal, oscillating). It is important to completely disjoin the zygoma at its frontal, maxillary, sphenoid, and arch articulations while protecting the intraorbital contents with a malleable retractor. C, The entire zygoma is then repositioned into an anatomic position under direct vision. A bony gap or significant stepoff along the arch, as well as the orbital floor, may be grafted. Recontouring the orbital floor is more salient in correction of the orbital soft tissue deformities, whereas the zygomatic arch is relevant to facial width. Significant bony orbital volume reduction is possible in this powerful procedure. Rigid fixation of the zygoma with the assistance of temporary wire fixation in one or two points (e.g., zygomaticofrontal) is helpful. Soft tissue closure of the incisions may be accomplished in the usual fashion with the inferior crus of the lateral canthal tendon approximated carefully to the common tendon with a small absorbable suture, followed by cutaneous repair. The malar soft tissue should be suspended to obviate postoperative soft tissue ptosis, and, lastly, a temporary tarsorrhaphy is performed.
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A B C
D E
Figure 11-2 In patients who have enophthalmos, and a volume discrepancy exists between the intraorbital contents and the acquired orbital bony volume, an ideal procedure is to osteotomize the zygoma and reposition it to create a smaller bony orbit. This should more closely resemble the normal anatomy and be appropriate for the soft tissue contents. Sometimes a bone graft is necessary to further reduce volume, especially in the floor region, which does not reduce well after osteotomy, especially in the late post-traumatic cases. A, A 29-year-old woman suffered right facial trauma and repair approximately 2 years before presentation to me. Coronal view of her orbits on computed tomographic scan demonstrates the large orbital volume discrepancy between the treated right side and the untreated left side. Her most significant complaints are related to her appearance. B, I performed multiple osteotomies and mobilized the zygoma by way of hemicoronal, gingivobuccal, and transconjunctival eyelid incisions. Here the zygomaticosphenoid junction and arch of the zygoma are exposed for osteotomy. C, The zygomaticomaxillary and nasal buttresses are exposed by way of a gingivobuccal approach and are then osteotomized. The transconjunctival approach to the zygomaticomaxillary junction is not shown here because this approach has been seen previously in the text (Chapter 6). D, This is the patient at presentation 2 years after injury and repair by other surgeons. Note the significant enophthalmos and inferiorly displaced eye (low eye) with a superior sulcus deformity on the right. She also has a depressed malar eminence. E, This is the patient
1 year after I performed a zygoma repositioning and autogenous bone graft. Note the significant improvement in enophthalmos, superior sulcus deformity, and elevation in the globe produced by the orbital volume reduction. The malar eminence is also normalized compared with the contralateral side.
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TREATMENT OF
EXOPHTHALMOS
Exophthalmos or protrusion of the globe anteriorly presents as a typical set of signs and symptoms, which, like enophthalmos, are almost pathognomonic. The most common underlying condition associated with either unilateral or bilateral exophthalmos is Graves’ disease. These patients may present with a spectrum of infiltrative disorders, which may range from mild true upper lid retraction secondary to infiltrative disease involving Müller’s muscle and other structures. Alternatively, they may present with or progress to severe exophthalmos with corneal exposure and even optic nerve compression due to significant infiltration and swelling of the extraocular muscles and orbital fat posterior to the equator of the eyeball at the orbital apex. Indications for orbital decompression fall into the categories of intractable exposure or compression permanently endangering vision. These are well described (e.g., NO SPECS classification) and appropriate for various graded decompression procedures. The purpose of this discussion is not to review the literature and procedures for orbital decompression but to focus on the underlying soft tissue abnormalities that in moderate to severe cases of orbital Graves’ diseases should be addressed with selective well-executed osteotomies in conjunction with appropriate soft tissue procedures. They should not be treated with simple gross fractures into sinuses and/or soft tissue “masking procedures.” An understanding of why these osteotomies work in rearranging specific soft tissue elements allows us to integrate all the useful anatomy already covered.
The procedure of choice for these unilateral cases is based on lateral orbital wall repositioning with selective decompression of the other walls of the orbit. As in the treatment of late enophthalmos, the zygoma and its bony articulation are the key anatomic structures to be addressed. In these cases, the upper segment of the zygoma (above the maxillary buttresses, lateral to the infraorbital nerve and anterolateral to the greater sphenoid wing) is osteotomized and rotated anteriorly or counterclockwise on the right side and clockwise on the left, producing a “valgus” fracture. The incisions for exposure are similar to those used in the enophthalmos procedure, including coronal, vestibulobuccal, and transconjunctival routes. The lateral retinaculum (lateral canthal tendon) should be left intact when possible because the location of the zygoma produces a
lateralization of Whitnall's tubercle and hence traction or tightening of the tendon. This elevates the lower eyelid and defines the lateral canthus more anteriorly on the globe. A formal canthoplasty with bony fixation may be performed should disinsertion of the lateral canthal tendon occur. I sometimes electively perform a soft tissue canthopexy or tightening of the lateral canthus and thereby elevate the lower eyelid beyond what would be produced by rotating the zygoma alone.
The decompression of the orbital floor and ethmoid region is well accessed by way of the transconjunctival route, again sweeping posteriorly to the lacrimal fossa. The lateral wing of the sphenoid can be resected up to the external aspect of the middle cranial fossa. Periorbita must be incised widely; however, intractable diplopia and other complications can be avoided by incising it from the ethmoid medially and around to the superior and lateral orbit. I prefer to leave the inferior periorbita intact. Gentle pressure is placed on the globe to allow herniation of orbital contents, and every attempt is made to match the contralateral side when it is normal. The arch of the zygoma may require a bone graft to maintain curvilinear facial width and appearance. A temporary tarsorrhaphy is performed and left for the first postoperative week. In cases of bilateral exophthalmos, one may consider the above procedure either in stages or concomitantly, or one may perform a subcranial Le Fort III minus the Le Fort I segment. Simply put, this is an en bloc bilateral orbital advancement above the level of the maxillary teeth (Figs. 11-3 and 11-4).
P E A R L S A N D P I T F A L L S
1.Soft tissue manipulation alone is inadequate for the correction of cosmetic problems in a subgroup of patients, most of whom suffer from orbital volume/soft tissue discrepancies.
2.Soft tissue orbital surgery should almost always follow bony procedures.
3.Limited incision exposure techniques for osteotomies of the zygoma and orbit are technically demanding and are limiting to ideal positioning of osteotomized segments.
4.Although all the pathophysiology in Graves’ disease of the orbit is related to soft tissue changes, it is the “valgus” maneuver of the zygoma along with other bony osteotomies that are most effective in cosmetic and functional corrections.
5.Nonfunctional aesthetic abnormalities in Graves’ disease and other abnormalities of the orbit are sometimes best treated with osteotomies and other bone-altering procedures.
6.In orbital expansion procedures, the inferior periorbital is best left intact to obviate inferior dystopia of the eyeball.
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ORBITAL EXPANSION
AOsteotomize zygoma and rotate nasally 
Inferior displacement of lower lid with scleral show
Osteotomy line
BPartial removal of orbital walls and periorbita incised
Rotation of zygoma tightens lateral canthal tendon and elevates lower lid
Bone graft
Figure 11-3 The patient with exophthalmos presents with a bony and soft tissue volume discrepancy opposite to that found in the case of enophthalmos. Here the bony orbit is too small for the soft tissue contained within. Soft tissue procedures alone (“masking”) are partially effective both cosmetically and functionally only in mild cases; however, they do not anatomically address the underlying pathophysiology in a global fashion. Standard intraorbital decompression procedures (without zygoma repositioning) are sometimes effective in retrodisplacing the globe and in decompression but are not effective in addressing the adnexal and canthal positional deformities and are not applicable as a single “cosmetic” procedure in the patient who has significant exophthalmos secondary to orbital thyroid disease or other processes that are “nonfunctional” in that the cornea is adequately wetted (with drops/gels/ointments) and there is no evidence for orbital apex compression. The orbit in these cases is expanded in two ways: (1) a valgus maneuver of the zygoma and (2) bone resection and incision of the periorbita with herniation of the orbital contents are performed. Exposure is gained as in the enophthalmos correction. The zygoma is osteotomized in a nonanatomic fashion in that the bone segment may be mobilized outside the normal articulations or suture lines. For example, a beveled osteotomy above the zygomaticofrontal junction and through the body of the zygoma should be carried out when indicated, and these may be tailored to conform to individual anatomy. A, Access incisions are similar to those previously described; however, care should be taken to preserve the insertion of the common lateral canthal tendon. It may be reattached to bone if necessary. The orbital walls are resected in the ethmoid, maxillary, and sphenoid region. The transconjunctival incision is useful here in that it can be carried behind the lacrimal fossa with excellent exposure of the medial orbital wall and ethmoid complex. Laterally, I resect the zygoma behind the orbital rim up to the greater wing of the sphenoid and bur down the latter, short of exposing the middle cranial fossa. Periorbita is incised laterally, superiorly, and medially but not inferiorly to avoid glove depression; and light pressure is used to accentuate herniation of orbital contents. B, The zygoma is repositioned by rotation and slight impaction and rigidly fixed, with bone grafts applied where needed (A [black arrow] and B). Contouring (bur) is helpful at the junction between the rotated and nonosteotomized bone segment to soften the step off. Closure is completed with a temporary tarsorrhaphy.
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A B
Figure 11-4 Enophthalmos or protrusion of the globe is ideally corrected by manipulating the bony orbital confines and increasing its volume. Osteotomies through the zygoma and adjacent bone with rotational repositioning is a very powerful technique for repositioning not only the affected soft tissue structures in the deep and middle orbit but also the anterior adnexal structures. A, A 22-year-old woman presented with unilateral left orbital Graves' disease and 5 mm of proptosis without optic nerve compression and with corneal exposure that is controlled with wetting agents. She is especially bothered by her appearance and cites multiple examples of how social, school, and work interaction with others is compromised. Note upper and lower eyelid malposition. B, The lateral orbital wall is repositioned by way of osteotomies performed through the coronal and vestibulobuccal routes. The orbital floor and medial orbit is accessed by way of a transconjunctival incision that is extended behind the posterior lacrimal crest. In this photograph, the osteotomy lines are delineated in blue. The temporalis muscle is reflected only in its anteriormost extent to gain access to the zygomaticosphenoid junction. Continued
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C |
D |
Figure 11-4 Continued |
C, The zygoma is rotated and repositioned (clockwise in this case) and rigidly fixed. I prefer to rongeur the zygoma and |
sphenoid articulation surfaces to create the large lateral orbit gap. The orbital floor and ethmoid walls are removed, and the periorbita is opened from the ethmoid region medially through the superior and lateral region, leaving the inferior periorbita intact. A small bone graft is usually needed along the arch of the zygoma to maintain facial width and contour. D, The patient as seen in A approximately 1 year postoperatively after lateral orbit repositioning. She is asymptomatic without corneal exposure and diplopia. The proptosis is alleviated, and the lid position is satisfactory, closely matching the contralateral side. The superior sulcus on the operated side is more concave, owing to the volume redistribution caused by the surgery. I am planning a small soft tissue procedure to fill the sulcus deformity.
REFERENCES
Chan CH, Spalton DJ, McGurk M: Quantitative volume replacement in the correction of post-traumatic enophthalmos. Br J Oral Maxillofac Surg 38:437-440, 2000.
Chen CT, Chen YR: Endoscopically assisted repair of orbital floor fractures. Plast Reconstr Surg 108:2011-2018; discussion 2019, 2001.
Clavser L, Galie M, Sarti E, Dallera V: Rationale of treatment in Graves ophthalmopathy. Plast Reconstr Surg 108:18801894, 2001.
Hobar PC, Burt JD, Masson JA, et al: Pericranial flap correction of superior sulcus depression in the anophthalmic orbit. J Craniofacial Surg 10:487-490, 1999.
Karacaoglu E, Tezel E, Guler MM: Rotation ligamentoplasty for the correction of epicanthus inversus. Ann Plast Surg 45:140-144, 2000.
Longaker MT, Kawamoto HK Jr: Evolving thoughts on correcting posttraumatic enophthalmos. Plast Reconstr Surg 101:899-906, 1998.
Van den Bosch WA, Tjon-Fo-Sang MJ, Lemij HG: Eyeball position in Graves orbitopathy and its significance for eyelid surgery. Ophthalmic Plast Reconstr Surg 14:328-335, 1998.
Zabramski JM, Kiris T, Sankhla SK, et al: Orbitozygomatic craniotomy: Technical note. J Neurosurg 89:336-341, 1998.
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C H A P T E R T W E L V E
Laser Resurfacing in the
Periocular Region
Amy B. Lewis and Henry M. Spinelli
Cosmetic skin rejuvenation currently stands at an interesting juncture between the ablative resurfacing techniques developed during the 1990s and the nonablative skin rejuvenation technology of the 21st century. During the 1990s, treatment options for rhytids and atrophic scars were limited to ablative laser resurfacing that required an extended healing period as well as invited post-treatment complications. Nonetheless, ablative resurfacing is still considered to be the most effective skin resurfacing treatment, yielding the most dramatic results. With the turn of the century, medical technology has redirected its efforts to create a second treatment option for patients with mild-to- moderate rhytids or atrophic scars. This nonablative technology attempts to stimulate the skin to produce collagen without the trauma of destroying the epidermis in the process.
As a result of these developments laser surgeons are now faced with the ever-more complicated task of evaluating the appropriate treatment for their patients given ever-present financial and time constraints. Compounding the dilemma is the fact that as the number and complexity of these choices increases, so do the nuances between them. We will attempt to simplify the choices to be made. A common request from patients is to improve the aging appearance around the eyes. This is often the first cosmetic region to show the effects of time and solar damage. However, it is also the most delicate and often difficult to treat with lasers. This survey of the various laser skin rejuvenation techniques that are available to laser surgeons today is intended to provide an overview of, and perhaps introduction to, this technology.
ABLATIVE VS. NONABLATIVE LASERS
When discussing laser technology, it is important to understand which lasers are used and how they affect the skin and the rejuvenative process.
The two most commonly used ablative resurfacing lasers are the ultrapulsed CO2 laser and the erbium:yttrium-aluminum-garnet (YAG) laser. The CO2 laser ablates approximately 100 m of tissue and leaves an additional 50 m of thermally damaged tissue. The erbium:YAG laser ablates less tissue, between 20 and 40 m, and leaves thermal damage of an additional 20 to 30 m. However, both lasers cause sufficient enough damage to the epidermis and dermis that specific precautions, to be discussed later, should be taken by both the physician and the patient. Nonablative lasers include the modified diode, erbium:YAG, neodymium:YAG (Nd:Yag) or pulsed dye lasers calibrated to specifically induce the skin to produce collagen. However, individual laser manufacturers have differing technologic theories as to the optimal fluences needed to best induce collagen production. These theories originated in anecdotal evidence provided by physicians and patients that pulsed dye lasers treating vascular conditions produced the unexpected effect of tightening collagen. From this unanticipated side effect, laser manufacturers began investigating the rejuvenation potential of nonablative lasers.
The novelty of nonablative technology has prevented any long-term studies or definitive data to be produced.
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The first nonablative lasers premiered commercially in the United States at the American Academy of Dermatology Convention in Washington, D.C., in March 2001. Consequently, as of yet, there is no generally used or recognized nonablative laser used by most laser surgeons. Physicians are reluctant to commit themselves to particular nonablative laser technology until more concrete data are produced by laser manufacturers or physicians.
ABLATIVE LASERS
Although the prospect of smoother skin free of wrinkles or scars may be enticing to the patient, the physician is obligated to speak frankly about both the logistical and the psychological impact of ablative laser resurfacing. This discussion should begin with the realistic aesthetic evaluation of how laser resurfacing can effectively treat rhytids or textural changes caused by trauma, actinic damage, biologic aging, or prior surgery. The physician should outline the amount of time that will be required for the patient to heal as well as prepare the patient for the impact of how the patient's face will look immediately after laser treatment and as it heals. The patient needs to understand that the first 10 days after treatment will require vigorous aftercare because of significant edema, erythema, some crusting, and occasional discomfort. In addition, the patient should expect at least 3 to 6 months of mild-to-moderate erythema, which can be concealed with camouflage makeup and sunglasses and, as healing progresses, simple foundation makeup.
Once the physician has explained the healing time required as well as the psychological impact of an ablative laser treatment, the patient should be given adequate time to process this information. A patient will also need to consider how this procedure can be scheduled among professional, family, social, and other personal obligations. Bear in mind, that as with most cosmetic procedures, especially those requiring significant “down” time, physicians must be prepared to provide the patient with ample emotional support. Ultimately, an informed and prepared patient will return to the physician to do laser resurfacing with realistic expectations about the procedure, aftercare, and results.
Erbium:YAG vs. CO2 Laser
CO2 laser resurfacing is considered the most effective form of treatment available for extensive cutaneous
photodamage, moderate-to-severe rhytids, moderate-to- severe atrophic scarring or fibrosis, and other epidermal and dermal lesions. With a wavelength of 10,600 nm, CO2 lasers emit high-energy beams that predictably vaporize 20 to 60 m of tissue per pass and leave acceptably narrow zones of residual dermal damage.
The CO2 laser’s effects are primarily photodermal, and the residual dermal necrosis modulates wound healing, thus substantially affecting the ultimate cosmetic outcome. The heat generated within tissue intraoperatively causes immediate collagen shrinkage of 15% to 25%; and during the subsequent healing period, continued collagen contraction and reorganization are evident over the ensuing 12 to 18 months.
A number of companies provide CO2 laser technology. A 2- to 3-mm spot size is available for delicate areas directly under the eyes or in the immediate lateral and medial canthi. A larger scanner can be employed for the temples and larger areas to enhance the quickness of the procedure. The skin is vaporized laterally to the temples and inferiorly to the full extent of the rhytids. A common setting for the 3-mm collimated handpiece is 50 mJ/pulse at 3 to 7 W. Usually two to three passes are performed in the periorbital region and, between passes, icewater-soaked gauze is used to wipe away any debris. Eye protection for the patient can be accomplished in several ways. Many laser surgeons prefer to use water-soaked gauze pads over the eyes so that they may reposition the gauze pads appropriately as the laser moves around the area being treated. However, this requires additional comfort and skill with the procedure. Consequently, standard eye shields placed over the cornea are often a more preferred approach.
The erbium:YAG laser emits a wavelength of 2940 nm, which corresponds specifically to the main absorption peak of water and consequently is absorbed 12 to 18 times more efficiently by superficial cutaneous tissue than the CO2 laser. Irradiated tissue is immediately and forcibly ejected from the surface of the skin, permitting most of the thermal energy generated to escape. Therefore, the erbium:YAG laser resurfaces skin photomechanically whereas the CO2 laser remodels skin photothermally.
The erbium:YAG laser is an excellent option for the treatment of mild-to-moderate rhytids on younger patients who have less actinic damage and shallower wrinkling in the periorbital region. In addition, the erbium:YAG laser appears to create less thermal diffusion and damage and thus shortens the reepithelialization of the skin, usually 5.5 days after the erbium:YAG resurfacing, compared with 8.5 days for CO2 laser resurfacing,5 as well as the time needed for resolution of
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the postoperative erythema and edema. Laser surgeons must remember, however, that unlike the CO2 laser the erbium:YAG laser is not an ideal hemostatic device and is associated with petechial bleeding from the dermal capillary nexus.
The variability of treatment afforded by these two lasers has led laser surgeons to explore more creative applications by combining the CO2 laser and erbium:YAG laser into a single treatment protocol. For patients presenting varying levels of photodamage and lesional involvement, some laser surgeons have opted to treat less severely damaged areas with the erbium:YAG laser while reserving treatment with the CO2 laser for the more ravaged areas that would require more drastic improvement.
Another interesting combined modality tries to capture the advantages offered by both the erbium:YAG and the CO2 lasers. The resurfacing protocol is superior because it achieves maximum cosmetic improvement while minimizing morbidity. In some cases we like to begin by treating the affected area with a single pass of the ultra-pulsed CO2 laser set at 300 to 500 mJ, immediately followed by two passes of the erbium:YAG laser with a 3-mm spot size. The single pass of the CO2 laser creates dermal remodeling by collagen shrinkage while minimizing collateral damage. The erbium:YAG laser is used to ablate the epidermis mechanically and overall improve texture. It also serves to lessen the thermal zone of damage dispersed by the CO2 laser.
Because both the CO2 laser and the erbium:YAG laser have wavelengths that fall within the invisible infrared spectrum, the preoperative, intraoperative, and postoperative care protocols are similar for ablative resurfacing regardless of whether it is CO2 laser, erbium:YAG laser, or a combination of both used on the patient.
Pretreatment
Starting 2 to 4 weeks before the procedure, patients may be started on 0.025 to 0.05% retinoic acid cream at night, hydroquinone 4% cream twice daily, and/or 5% to 10% glycolic acid lotion. However, this is still controversial, and many laser surgeons choose not to pretreat with topical agents. Sunscreens containing ultraviolet A and B blockers as well as a sun protective factor of 15 or higher should be used daily by the patient. The best sunscreen available for the patient before and after treatment is one containing mexoryl (Anthelios 60+: La Roche-Posay, Paris, France).
A preoperative questionnaire is helpful for the physician to learn about the patient’s history of
smoking, postinflammatory hyperpigmentation or hypopigmentation, radiation therapy, scarring, herpes simplex virus (HSV) infections, and some use of isotretinoin (Accutane: Roche Laboratories, Nutley, NJ). In particular, some surgeons believe that patients with a history of isotretinoin use within the previous 1 to 2 years may not be eligible for ablative laser resurfacing.
Beginning 1 day before laser resurfacing patients should be placed on preoperative antibiotics (erythromycin or dicloxacillin, 500 mg orally, two to four times a day, or azithromycin [Zithromax Z-pack]) and antiviral therapy (acyclovir or its derivatives) and continue this regimen for 7 days thereafter or until total reepithelialization is achieved.
Intraoperative Care
Safety precautions must be followed when using invisible infrared laser, which can inadvertently discharge and burn areas outside the field of treatment. The operating room door must have a cautionary laser sign displayed, and all personnel must wear wavelengthspecific eye protection. Surgical drapes should be fireresistant or moistened, and oxygen delivery should be turned off when using the laser. A water-filled spray should be ready in the treatment area to extinguish any fire. Finally, the erbium:YAG laser produces a large plume of dust containing water vapor and ejected particles. This “tissue dust” may be harmful to inhale, and all personnel must wear laser facemasks that filter particles as small as 1 m. A strong smoke evacuator is mandatory to capture the plume of dust.
During treatment, the erbium:YAG laser makes a loud popping sound and the CO2 laser makes a more muted sound with each pulse. There is more airborne debris and very little gross contraction of tissue during the first pass of erbium:YAG irradiation. In contrast, there is little debris during the first pass and immediate physical contraction during the second and third passes of the CO2 laser. The erbium:YAG laser creates a focal pinpoint bleeding that increases with each pass.
Generally, if only one or two cosmetic units are being resurfaced, local anesthesia with nerve blocks is used in addition to mild sedative and pain reducers such as a diazepam and meperidine cocktail. With the erbium:YAG laser, some suggest adding only topical anesthetic cream such as lidocaine (ELA-Max) or topical butacaine. However, if a full face resurfacing with the CO2 laser is planned, intravenous sedation is usually necessary. The periorbital area, however, is difficult to anesthetize with nerve blocks and is a very sensitive area
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to treat. Periorbital laser treatment is often combined with another procedure, such as a blepharoplasty, that may require intravenous sedation. If done alone, the option of topical anesthesia with the aforementioned cocktail or sedation is offered to the patient. It is easier for the laser surgeon to effectively treat the periocular area if the patient is not moving or wincing. Therefore, we suggest conscious sedation for resurfacing around the eyes unless an excellent anesthetic block and adequate ocular protection are provided.
Postoperative Care
The number and variety of post laser care regimens is even larger than the therapy choices available to begin with. Basically, after the laser procedure, either nonocclusive or occlusive dressings may be used. This is a controversial point in laser care at this time because each technique has distinct advantages as well as drawbacks.
Occlusive dressings are applied by the surgeon immediately after the treatment and are left in place for several hours to a few days, thus requiring minimal patient involvement in wound management. This method reportedly reduces postoperative pain and modestly accelerates the initial healing process. However, occlusive dressings may prevent visual inspection of the wound and increase the risk of bacterial or yeast infection on the skin if left intact for an extended period of time. These include Second Skin (Spenco Medical Corporation, Waco, TX), Vigilon, and other hydrogel derivatives.
Nonocclusive dressing involves frequent application of healing ointments such as Catrix 10 Correction Cream, Aquaphor (Beirsdorf, Inc., Norwalk, CT), Elta Renew Cream, or pure petrolatum by the patient. The patient also treats the wounds with application and soaks to decrease edema and any buildup of adherent crust. This method decreases the risk of infection and allows the surgeon to visualize the wound bed and intervene promptly if complications occur. However, postoperative pain is greater, there is significantly more crusting, and initial healing may be slightly slower. Most importantly, this method is highly dependent on strict patient compliance, and this should be taken into account by the surgeon considering postoperative care options. Whether the surgeon chooses the postoperative occlusive or nonocclusive technique is less important than keeping any uncovered area moist by the application of one of the previously mentioned ointments.
NONABLATIVE LASERS
The newest generation of laser rejuvenation is still in its early stages but theoretically promises to present the opportunity for laser skin rejuvenation to an increasingly expanding array of patients. The procedure will likely cost less, requires no recovery period, and, in fact, does not even ablate the epidermis. Patients could theoretically rejuvenate their appearance without even their closest friends being aware of their going through the process. One caveat to this treatment is the “too good to be true” phenomenon, that is, there are no long-term quality studies regarding the efficacy or extent of the benefit of these lasers. As more laser surgeons collect data based on patient treatment, a more thorough clinical review of this procedure will be necessary. However, this survey of laser skin rejuvenation techniques is intended merely to familiarize the reader with the new and continually evolving technology of nonablative lasers.
Generally there are three theories as to why nonablative lasers cause skin rejuvenation. Individually, one of these three theories may explain the science behind nonablative technology; however, it is more likely that these factors work together in varying capacities to create the resulting skin rejuvenation.
First, photothermal heating in the dermis may produce a nonspecific dermal wound response inducing fibroblast activation and subsequent collagen remodeling. Essentially, the photothermal heating tricks the dermis into thinking that it has been injured and stimulates collagen and fibroblast production to repair itself. Second, nonablative technologies may cause displacement of elastic photodamaged dermis, which is replaced by a more normal-appearing dermal matrix. By breaking down the damaged tissue, the dermis is able to replace it with more regularly structured healthy tissue. Third, laser-induced endothelial disruption leads to cytokine activation, which may induce subsequent collagen remodeling. In other words, by injuring but not destroying the dermal microvasculature, the injured vessels release cytokines to stimulate collagen production. Heat shock protein, vascular endothelial factors, and β-fibroblastic growth factors have all been shown to be up-regulated after clinical photoendothelial interaction. Clearly, there are measurable changes that occur as a result of nonablative lasers; however, it may take another generation or two of mechanical devices to translate these changes into a broadly useful tool.
As stated earlier, how and to what extent these various dermal reactions contribute to the final result of im-
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