Open-sky isolated subtotal Muller’s muscle resection for ptosis surgery: a review of over 300 cases and assessment of long-term outcome

Abstract

To evaluate short- and long-term success rates on isolated subtotal Muller resection in over 300 cases of ptosis over a 10-year period. Clinical records were retrospectively evaluated for aetiology and severity of ptosis, levator function, response to phenylephrine, pre- and postoperative margin reflex distance of the upper lid (MRD1), postoperative lid contour and symmetry, complications and follow-up duration. change in MRD1 and eyelid contour. Surgical success: postoperative MRD1 ≥2 and ≤4.5 mm, symmetry to within 1.0 mm and satisfactory contour. All patients were also sent patient satisfaction questionnaires, and invited to attend for a longer-term assessment of their surgical outcome. In total, 92 and 95% of 309 eyelids met all three criteria for success after an average follow-up of 4 and 47 months, respectively. Mean improvement in MRD1 was 2.56 mm. In all, 97% had postoperative MRD1 of ≥2 and ≤4.5 mm and over 99% had an excellent contour. Altogether, 95 and 89% were within 1.0 and 0.5 mm symmetry of the fellow eye, respectively. In total, 51% of eyelids continued to rise, 17% maintained the same initial postoperative height, and 32% dropped by 1 mm or less. In all, 92% felt that their initial postoperative eyelid height had been maintained. Only 2% required repeat surgery and minor complications occurred in 4%. Isolated subtotal Muller's resection is safe and effective for the repair of the majority of ptosis with moderate-to-good levator function. It results in a more predictable height, which is maintained over time, less frequent contour abnormalities, and lower re-operation rates compared with anterior levator advancement.