Ординатура / Офтальмология / Английские материалы / Asian Blepharoplasty and the Eyelid Crease_Chen_2006

extends to the inferior orbital rim (Fig. 2-14). Epicanthus tarsalis rises from the upper lid crease and merges into the skin near the medial canthus (Fig. 2-15). Johnson called this configuration ‘Mongolian eye’. In epicanthus inversus, the fold rises from the

lower lid and extends to the upper lid over the medial canthus (Fig. 2-16).

Of the four types of epicanthus described by Johnson,18 Asians usually have epicanthus tarsalis. This configuration is a subtle fold of skin that arises from

the medial canthal angle and courses laterally, forming a small medial upper lid fold, toward a point between the medial third and the medial half of the upper lid. Some Asian children may appear to have an epicanthus palpebralis (Fig. 2-17A,B), in which the fold covers the upper and lower lids equally across the medial canthus. With growth and development, however, the fold appears to be transformed into a medial upper lid fold. This may be the result of the development of the nasal bridge (Fig. 2-18). The medial upper lid fold is often seen in patients who already have a natural crease (Fig. 2-19).

Most articles19–21 in the literature seem to focus on the correction of epicanthus palpebralis and epicanthus inversus. The latter is a condition more often associated with the syndrome of congenital blepharophimosis. Most repairs are a variation of the double-Z or Y-V- plasty. These techniques are ill-suited to the correction of the medial upper lid fold in Asians.

The author3,4,22,23 tends to be conservative in the correction of these medial upper lid folds, for the following reasons. First, it is hard to call something pathologic when it occurs naturally in a large percentage of the population, considering that there are at least two to three billion Asians living on this planet. Second, Asians tend to have thicker skin near the nasal bridge, which is more reactive and prone to hyper-

trophic scarring in the thick medial canthal skin area. Third, a medially tapered crease that merges with the origin of a mild medial upper lid fold or ‘epicanthus tarsalis’ provides an aesthetically natural crease, as seen in those Asians who do have a lid crease. Fourth, the fold often evolves and regresses as the individual reaches adulthood. These small medial canthal folds are almost always a very small version of a true epicanthus and do not warrant being labeled with a term implying pathologic status.

Upper Tarsus

Asians tend to be smaller built than Caucasians. Their upper tarsus is often only 6.5–8.5 mm in vertical dimension compared to Caucasians,22,23 in whom the average is 10 mm, ranging from 9.5 mm upwards.

Vascular Supply of the Upper Eyelid

Kawai et al.24 studied the upper eyelids in seven fresh cadaver specimens, presumably of Asian origin. The specimens were systemically injected with a lead oxide–gelatin mixture and stereoscopic radiographic records of the anastomotic vessels were made, followed by macroscopic dissection. The authors found four

A

Chapter 2 Comparative Anatomy of the Eyelids

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Fig. 2-17 (A) A 3-year-old child and (B) a 1-year-old child with slight epicanthal fold (a more appropriate term would be medial upper lid fold). The presence of this fold in Asian children frequently makes them appear to have esotropia (inward turning of the visual axis).

main arterial arcades in the upper eyelids, i.e. marginal, peripheral, superficial orbital and deep orbital. They described vertical branches arising from each arcade, with the vertical branches of the superficial orbital arcade lying anterior to the preseptal orbicularis, the vertical branches of the deep orbital arcade behind the same orbicularis, and the vertical branches between

the marginal and peripheral arcades lying both in front of and beneath the upper tarsal plate (Fig. 2-20).

The marginal and peripheral arcades were formed by the anastomosis of the medial and lateral palpebral arteries, which were branches of the ophthalmic and lacrimal arteries. The marginal arcade was situated between the orbicularis and the tarsal plate; it lay just

anterior to the lower margin of the tarsal plate and gave off small vertical branches that ascended tortuously on both sides of the orbicularis and on both sides of the tarsal plate. These branches provided fine vessels to the skin, muscle, and tarsal plate. In addition to these small vertical branches, the marginal arcades provided fine vessels to the free edge of the upper lid. The peripheral arcade coursed in Müller’s muscle along the superior tarsal border, and gave off vertical branches that descended on both sides of the tarsal plate. The descending branches (of the peripheral arcade) running over the tarsal plate anastomosed with the ascending branches arising from the marginal arcade, whereas the descending branches running beneath the tarsus separated into fine vessels and formed a vascular plexus with the ascending branches arising from the marginal arcade (Fig. 2-21).

The superficial and deep orbital arcades were formed by the anastomosis of the branches of the zygomatico-orbital artery, the transverse facial artery, or the frontal branch of the superficial temporal artery laterally and the branches of the supratrochlear artery, the ophthalmic artery, or the medial palpebral artery medially. Of these, the supratrochlear artery contributed significantly to both the superficial and deep orbital arcades, the latter running along the superior orbital rim. The terms superficial and deep refer to the level of the preseptal orbicularis oculi layer. Both the superficial and deep orbital arcades gave off vertical branches that descended anterior and posterior to the orbicularis and anastomosed with ascending branches from the marginal arcade. The authors further noted that the vertical vessels running over the orbicularis oculi traversed obliquely (connecting the marginal to

the superficial arcade) rather than vertically, as with those that ran under the orbicularis, which connected the deep orbital arcade to the marginal arcade. They did not observe any single dominant intramuscular vessel within the orbicularis and deduced that its blood supply must therefore come from the fine vessels from the vertical branches. The authors implied that their method of study provided an undistorted assessment of the arterial structure of the upper eyelid.

Kim et al.25 reported an incidence of 25 among 230 eyelids where an artery thought to be a variation of the lacrimal artery was found superficial to the orbital septum and inferolateral to the levator muscle, at a location 4–5 mm medial from the lateral canthus. After piercing the levator it was observed to connect with the lateral palpebral artery behind the levator muscle. This lateral vessel was nicked in 14 cases and the bleeding arterial end retracted posteriorly behind the levator to

form a hematoma in the postaponeurotic space. This resulted in swelling, secondary ptosis, and difficulty in designing the lateral portion of the eyelid crease. Clamping the bleeding vessel was noted to be more effective than electrocautery when this occurred. Besides postulating that this might be a variant of a branch of the lacrimal artery, the authors also mentioned the possibility of a communicating artery between the peripheral arcade and the marginal arcade, or that this might be a medially displaced lacrimal artery. They mentioned that a cadaver dissection with latex injected into the ophthalmic artery was in progress.

In a somewhat similar study, Hwang et al.26 described the occasional presence of a laterally located artery, named the lateral septoaponeurotic artery (LaSA), as a branch of the superior lateral palpebral artery after it divides into the peripheral arcade, the

other being the marginal arcade. It was detected in 50 eyelids (11%) out of 460 operated on. (The superior lateral palpebral artery is a branch of the lacrimal artery, itself a branch of the ophthalmic artery.) The LaSA arises from the superior portion of the peripheral arcade, which runs along the superior tarsal border. From the peripheral arcade it pierces the levator aponeurosis and orbital septum at the upper level of the tarsal plate and is seen coursing on the surface of the orbital septum, about 5 mm inside the lateral canthus (Fig. 2-22). It anastomoses with a branch of the supraorbital artery at the superior aspect of the orbit. The authors commented that care should be taken in incising the lateral aspect of the septum, as severance of the LaSA may cause severe bleeding, hematoma formation and temporary ptosis, as well as retraction of the bleeding point and the formation of hematoma in the postaponeurotic plane. This may occur during use of the incisional method as well as the stitch method, which involves the placement of stitches over the lateral portion of the upper eyelid. This makes the surgeon’s task of following his designed crease difficult. The authors recommended specific visual examination of the lateral aspect of the orbital septum prior to any horizontal transection.

Hematoma may also occur separately following injury to the perforating branch of the marginal arcade:

there is occasionally a larger branch of the arcade running perpendicularly upward and piercing the aponeurosis near its insertion on the anterior surface of the upper tarsus, where it may be injured when the lower incisional skin edge is manipulated during surgery. This, however, is separate from the LaSA.

Facial Anatomy

Onizuka and Iwanami27 noted that the Japanese characteristically have a flat face, a mesocephalic head shape, and eyes that are not as deeply recessed in the orbit as in Caucasians. They noted that the lateral canthus is often 10° superior to the medial canthus. To produce an aesthetically pleasing result, they made an upper lid crease and removed any upper lid hooding to make the palpebral fissure appear wider and more open. Although the author does not believe that most Asians have a lateral canthus 10° above the medial canthus, some of Onizuka and Iwanami’s observations may be correct.

Concept of Facial Symmetry

Song,28 in 1988, wrote that since ancient times Chinese portrait artists have followed the rule of ‘horizontal

Asian Blepharoplasty and the Eyelid Crease

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Hairline

1/3

1/3

1/3

1/5

Fig. 2-23 Rule of horizontal thirds and vertical fifths. The symmetric thirds are the distances from the hairline to the brow, from the brow to the base of the nose, and from the base of the nose to the chin. The fifths are the distances from the auditory canal to the lateral canthus, from the lateral canthus to the medial canthus, from medial canthus to medial canthus, from medial canthus to lateral canthus, and from lateral canthus to external auditory canal.

thirds, vertical fifths’ when portraying the ideal face (Fig. 2-23). The symmetric thirds are the distances from the hairline to the brow, from the brow to the base of the nose, and from the base of the nose to the chin. The vertical fifths are identical to the western concept of the rule of fifths: the distance from the auditory canal to the lateral canthus, from the lateral canthus to the medial canthus, from medial canthus to the opposite medial canthus, from medial canthus to lateral canthus, and from lateral canthus to external auditory canal. An ideal palpebral fissure should be equal to one-fifth the

width of the face. Interestingly, most patients with a single eyelid who desire a lid crease tend to have a palpebral fissure that is narrower than the ideal (Fig. 2-24); their eyes appear inharmonious with the rest of the face.

In attempting to match eyelid and crease configuration to the facial configuration, Song also mentioned six facial shapes and the eight factors that influence a crease. The six possible facial shapes seen in the average Asian population include square, rectangular, round, oval, triangular (with the base down), and diamond.

The eight factors that influence a crease are really the three variants of crease height (broad, average and narrow) and the five combinations of crease shape.

1.Parallel crease, favored by Song for a person with a stable temperament and a mild personality, a cheerful and happy person.

2.Medially narrow (<7–8 mm) and laterally broad crease (7–10 mm). Used for a person with a rectangular, stern face, a serious person.

3.Laterally narrow and medially broad crease. The eyelid appears hooded down laterally, producing a sad face and a triangular eye configuration. Not recommended.

4.Broader medially and laterally than centrally. Considered inharmonious and not recommended.

5.Broader centrally than medially and laterally. Considered inharmonious and not recommended.

A broad crease (>10 mm) was advocated by Song for people with a rectangular face and a strong character, such as performers and actors. An average crease (7– 8mm) is chosen most often. A narrow crease (4–5mm) is recommended for people who want a crease but are self-conscious about others knowing about the operation. A nasally tapered crease and a parallel crease based on tarsal height give the face the most aesthetic harmony.

The conclusion is similar to what the author stated a year earlier in 1987,22 i.e. that a nasally tapered crease and a parallel crease based on tarsal height measurement give the best aesthetic appearance to the face.13

Summary

It is apparent that there is more than a superficial difference between Asian and Caucasian eyelids. In addition to the readily apparent differences in the size of the lids, crease shape, and crease height, there are also anatomic differences in the tarsus and fat pads, differences in the structure of the medial canthus, differences in facial configuration, and differences in the concept of beauty. All these factors should be taken into account in the performance of Asian blepharoplasty.

References

1.Millard DR Jr. Oriental peregrinations. Plast Reconstr Surg 1955;16:319–336.

2.Millard DR Jr. The oriental eyelid and its surgical revision. Am J Ophthalmol 1964;57:646–649.

3.Chen WPD. Upper blepharoplasty in the Asian patient. In: Putterman AM, ed. Cosmetic oculoplastic surgery, 3rd edn. Philadelphia: WB Saunders, 2000: Chapter 11.

4.Chen WPD. Review of Aguilar G. Complications of oriental blepharoplasty. In: Mauriello J, ed. Management and avoidance of complications of eyelid surgery. Vol. 3. Philadelphia: Field & Wood, 1994.