Eyelid Eversion for Visualization of the Upper Eyelid Lamellae

1. Marcus M. Marcet^1,2
2. Cheng Hong²
3. Bradley N. Lemke³
4. Tamara R. Fountain⁴
5. Steven Roth²
6. Sander R. Dubovy⁵

¹University of Hong Kong Eye Institute, Hong Kong, SAR
²University of Chicago, Chicago, IL, USA
³University of Wisconsin, Madison, WI, USA
⁴Rush University Medical Center, Chicago, IL, USA
⁵Bascom Palmer Eye Institute, University of Miami, Miami, FL, USA

Purpose: Although studies of the eyelid routinely include microanatomy, controversies remain in the arrangement of structures relevant to blepharoptosis surgery. The aim of our study is to describe the microscopic anatomy of the levator aponeurosis (LA) with the eyelid everted. The model presented herein is based on the natural separation of the lamellae when the eyelid is everted.

Methods: 20 orbits from 15 fresh cadaver heads were studied. Surface-coil MRI was obtained in 10 orbits with upper eyelids closed and then everted. The remaining 10 orbits with closed eyelids were used for anatomic comparison. After formalin fixation and exenteration, the orbits were sectioned and stained. The microscopic anatomy of the upper eyelids was studied histologically.

Results: In all 20 eyelids, bifurcation of the striated fibers of the levator palpebrae superioris muscle was seen near Whitnall's ligament. The LA was seen as a multilayered structure and was better visualized in the everted eyelids. The posterior LA inserted along the anterior tarsus and fused with the pretarsal orbicularis muscle. Both anterior and posterior layer LA attachments were more easily discernable in the everted eyelids. With eyelid eversion, there is lamellar separation of the postaponeurotic space.

Conclusions: To our knowledge, the anatomy of the aponeurosis in the everted eyelid has not been previously studied. Eversion causes separation of the eyelid's layers, alters the postaponeurotic space, and improves visualization of the lamellae. Eversion of the eyelid may improve intraoperative understanding of critical anatomy and promote safer and more effective eyelid surgery.