Purpose: Results of Muller’s muscle resection in patients with ptosis and its relationship with levator and Muller’s muscle function.

Methods: Prospective review of medical records of all pateints who underwent open sky Mullerectomy for correction of upper eyelid ptosis. The study period was from January 2008 to July 2009. Levator function, MRD1, Phenylepherine test result and extent of ptosis correction were recorded. Excised muscle tissue in few cases were subjected to histopathology.

Results: In 11 patients who underwent 13 mullerectomy procedures for correction of upper eyelid ptosis, MRD1 increased an average by 2.54mm. The amount of ptosis correction was 4.28mm in pateints with either good levator function and/or Muller's action and 1mm in patients where both responses to phenylepherine and levator functions were poor. Histopathology revealed both straited and smooth muscle tissue in the excised specimens in all cases.

Conclusion: Mullerectomy porbably involves plication of the posterior layer of the levator aponeurosis. Results of Muller's muscle resection is good in patients with good levator function and/or good Mullers action and poor if both Muller and levator function are poor.