Levator musculoaponeurotic transition and margin reflex distance
Author: Ivana Pereira
Base Hospital / Institution: University São Paulo – Brazil
ePoster presentation
Abstract ID: 24-399
Purpose
Levator musculoaponeurotic transition (LMAT) is the point where the muscular fibers of the levator become aponeurotic. The transition is visible in eyelids with normal levator function that underwent surgeries in which septal aperture is necessary, such as blepharoplasty with fat remodeling, lacrimal gland repositioning, and ptosis repair.The variability of the transition height from the upper tarsus is observed. In cases of aponeurotic ptosis accompanied by tarsal attachment dehiscence, the LMAT may ascend, thereby increasing the separation distance from the upper tarsus. This study analyzes the LMAT height and preoperative MRD (margin reflex distance) in patients with normal levator function who had undergone eyelid surgery.
Methods
We include 25 patients (22 females) with a mean age of 65,48 (6.89 SD) who underwent upper eyelid blepharoplasty with septum opening, lacrimal gland repositioning, and ptosis repair. Bilateral surgery occurred in 20 patients, resulting in 45 eyelids being analyzed. Critical surgical steps: opening the orbital septum over the preaponeurotic fat, exposure of the anterior surface of the levator muscle and aponeurosis, and measurement of the distance between the upper tarsal border and LMAT at the central eyelid area.We measured the preoperative MRD in the standardized photograph with ImageJ software. The LMAT distance was analyzed in 2 groups, according to MRD. Group 1 for MRD greater then 2.5 (without ptosis) and group 2 for MRD less then 2.5 (ptosis). Statistical analysis.The mean LMAT of each group was compared with a 2-tail T-Test.
Results
The mean MRD in group 1 was 3.78 mm (0.62 SD), and the mean LMAT was 4.77mm (1.88 SD). In group 2 the mean MRD was 1.75 mm (0.74 SD) and the mean LMAT: 6.09 (1.38 SD).The mean LMAT was significantly higher in ptosis patients.
Conclusion
The higher position of the LMAT in patients with ptosis could be related to aponeurosis tarsal attachment stretching due to degenerative changes. Additional histopathologic studies in this group of patients are necessary to confirm this hypothesis.
Additional Authors
| First name | Last name | Base Hospital / Institution |
|---|---|---|
| Patricia | Akaishi | University São Paulo – Brazil |
| Paula | Pegoraro | University São Paulo – Brazil |
