Immediate Postoperative Difference of Eyelid Height Based on Intraoperative Measurement of Levator Aponeurosis Advancement in Patients with Unilateral Ptosis.

Purpose: To determine the relationship between marginal reflex distance (MRD-1) outcomes and the distance of levator aponeurosis advancement.

Methods: This retrospective observational study included patients with acquired unilateral aponeurotic ptosis, who underwent small-incision anterior levator advancement. The distance of levator advancement, and intra-operative MRD-1 in the sitting position, were analyzed to determine a correlation between the two.

Results: Forty-eight patients were included. Results exhibited no direct relationship between advancement distance and MRD-1 measurements. Median and range of MRD-1 outcomes did not present a linear progression as the distance increased or decreased. A majority of advancement distances exhibited a median MRD-1 outcome of 4.00 mm (n = 3). Success criteria was met in 85.4% of surgeries performed.

Conclusion: Due to varying postoperative MRD-1 outcomes, surgical results cannot be accurately predicted using predetermined advancement distances. Confirming the final MRD-1 in the sitting position with subsequent adjustment is still recommended.