The Ophthalmology Department,  Universiti Malaysia Sarawak (UNIMAS), Kuching, Sarawak.

The Ophthalmology Department, Sarawak General Hospital, Kuching, Sarawak, East Malaysia.

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Case 41a

by Professor Chua Chung Nen

 

The following patients complain that their eyes appear different in size. However, the palpebral apertures are similar in both eyes and the levator excursions are equal in both eyes.

 

Figure 1. A 17 year-old boy complain that the right eye appears smaller than the left.

 

 

Figure 2. A 19 year-old woman complains her right eye has always been smaller than the left.

 

Figure 3. A 27 year-old man seeks surgery to make the two eyes equal in size.

 

Figure 4. A 18 year-old boy finds the left eye always look less alert than the right eye.

 

a. What is the diagnosis and how may this cause apparent asymmetry in eye size?

 

The apparent size differences in the two eyes of these patients is the result of congenital skin crease asymmetry. The eye that does not have the skin crease appears smaller because the upper eyelid skin forms a hood over the lid margin (Figure 5 a and b).

 

Figure 5 a and b. A lateral view of the first patient shows hooding of the skin over the right eyelid margin (a) which has no skin crease. The eyelashes are pushed downwards by the skin causing lash ptosis. The skin crease in the left eye acts as a barrier against skin hooding over the eyelid margin (b).

 

 

The height of the skin crease is due to the interplay of several structures1: the level of the orbital septum, the amount of subcutaneous fat and the level of insertion of the levator aponeurosis to the skin. In the East Asians (mainly Chinese, Koreans and Japanese), the skin crease is lower or absent in comparison with other races for the following anatomical reasons (Figure 6):

 

a. the fusion of the orbital septum to the levator aponeurosis is lower (usually below the superior tarsal border);

 

b. the presence of a thick subcutaneous fat layer and preaponeurotic fat protrusion prevent the levator fibres from inserting into the skin near the superior tarsal border;

 

c. the primary insertion of the levator aponeurosis into the orbicularis muscle and the eyelid skin occurs closer to the eyelid in the East Asians.

 

Figure 6. Picture showing the anatomical differences between the eyelids of an East Asians (right)

and a Caucasian (left). Blue arrows indicates the level of levator fibre insertion into the eyelid

skin and hence the skin crease2.

In addition, the insertions of the levator fibres to the eyelid skin and the orbicularis oculi are weaker in East Asians. Consequently, skin crease asymmetry is commoner in East Asians than other races.

 

b. Suggest ways of correcting the problem.

To achieve eyelid symmetry, the best way is to create a symmetrical skin crease in the eye without one. This may be achieved by two means:

 

a. Surgical method (Figure 7). The skin crease may be created by excising a strip of skin +/- orbicularis oculi or by the buried suture method.

 

b. Non-surgical method (Figure 8). The skin crease may be formed using sticker or glue. This may be  or by other cosmetic means (sticker or glue).

 

Figure 7. The insertion of three buried sutures allows the creation of a symmetric skin crease

in the left eye.

 

Figure 8. In patient who refuses surgery, sticker may be used to create a skin crease.

 

Figure 8. Symmetrical skin creases following sticker application in the right eye.

 

References:


1. The Asian upper eyelid: an anatomical study with comparison to the Caucasian eyelid. Arch Ophthalmol.

    1999 Jul;117(7):907-12. Jeong S, Lemke BN, Dortzbach RK, Park YG, Kang HK.

 

2. Strategies for a successful corrective Asian blepharoplasty after previously failed revisions.Plast Reconstr Surg.

    2004 Oct;114(5):1270-7 Chen SH, Mardini S, Chen HC, Chen LM, Cheng MH, Chen YR, Wei FC, Weng CJ.