Optimizing Management of Asymmetric Ptosis: A Comparison of Three Posterior Approach Resection Algorithms.

Abstract

The purpose of this study was to compare the efficacy of 3 resection algorithms in the management of patients with asymmetric ptosis. Patients undergoing bilateral Muller's muscle-conjunctival resection (MMCR) were identified. Standardized preoperative clinical photographs were examined and margin reflex distance 1 (MRD1) was measured using ImageJ. Patients presenting with ≥1 mm of asymmetry in MRD1 were included. Three groups were identified: variable (4:1 ratio, with the lower side receiving a greater resection), fixed (7 mm resection bilaterally), and tarsectomy (7 mm bilaterally + 1 mm of tarsus resected on the lower preoperative side). Postoperative MRD1 was measured from photographs obtained 3 months after surgery. The primary outcome was postoperative asymmetry. A total of 95 patients with a mean age of 71.0 ± 11.0 years were included. There was no significant difference in age ( p = 0.277) or length of follow-up ( p = 0.782) between the groups. Although the fixed tarsectomy group had significantly greater preoperative asymmetry ( p = 0.001), there was no significant difference in postoperative asymmetry ( p = 0.166). On multivariate analysis, preoperative asymmetry was the only significant predictor of postoperative asymmetry ( p < 0.001). Specifically, the surgical group was not a predictor of the primary outcome ( p = 0.723). Resection amount and technique did not predict postoperative outcomes in cases of asymmetric ptosis. This may support the hypothesis that changes in eyelid position and symmetry following MMCR is due to a dynamic system, rather than as a result of purely mechanical forces.