Orbital Septum Attachment on the Levator Aponeurosis in Asians. In Vivo and Cadaver Study

Abstract

Purpose To examine the anatomic relationships between the preaponeurotic fat pad, orbital septum, and the distal end of the anterior layer of the levator aponeurosis (DEALLA) in relation to the superior tarsal plate border. Design Prospective, clinical case series and experimental anatomic study. Participants Twenty-two upper eyelids in 11 Asian patients (average age, 76.5 years) and 10 postmortem upper eyelid specimens of 7 Asians (average age, 81 years). Methods The relationships between the orbital septum, DEALLA, preaponeurotic fat pad, and the superior tarsal plate border were examined in vivo, during upper blepharoplasty. In cadavers, the orbital septum was exposed and excised from the DEALLA, and the distance from the superior tarsal plate border to the DEALLA was measured at 3 points: the center of the palpebral width, and 2 points located 7 mm medial and lateral to the center. Main Outcome Measures The anatomic relationships of the orbital septum, DEALLA, and the preaponeurotic fat pad with the superior tarsal plate border. Results In vivo, the DEALLA was always located above the superior tarsal plate border, and the lower margin of the preaponeurotic fat was always positioned below the DEALLA and around the superior tarsal plate border. The lateral preaponeurotic fat in 4 eyelids showed extension beyond the superior tarsal border. In cadavers, the average distance from the superior tarsal plate border to the DEALLA was 3.7 mm centrally, 3.0 mm medially, and 0.9 mm laterally. In 3 specimens, the confluent part of the orbital septum and the levator aponeurosis reached the tarsus in the lateral area. Conclusions Orbital septum attachment on the levator aponeurosis in Asians seems to be situated above the superior tarsal plate border in vivo, but the preaponeurotic fat extends beyond the DEALLA, sometimes reaching the tarsal plate. In some cadavers, the confluent part was found to be situated on the tarsus laterally.