Purpose: To clarify histopathologically the structural features of blepharoptosis in prolonged hard contact lens wearers.
Design: Retrospective case-control study.
Methods: Biopsy specimens from identical sites at the levator aponeurosis and Mueller muscle from 15 long-term hard contact lens wearers were examined histopathologically (group 1). They comprised two men and 13 women with bilateral blepharoptosis ranging in age from 26 to 59 years (mean +/- SD, 44.4 +/- 10.70 years). The average length of hard contact lens wear was 25.4 years (range 12 to 40 years), and the average spherical equivalent refractive error was -9.100 diopters (range -2.825 to -20.375 diopters). We also examined specimens from 15 patients with involutional blepharoptosis who underwent levator resection; they comprised three men and 12 women ranging in age from 64 to 79 years (mean +/- SD, 72.3 +/- 4.38 years).
Results: All patients in group 1 manifested fibrosis and negligible fatty degeneration in Mueller muscle. In group 2, we detected mild fibrosis in Mueller muscle and fatty degeneration of the aponeurosis and Mueller muscle.
Conclusions: Prolonged hard contact lens wear induces fibrosis in Mueller muscle and may result in contact lens-induced blepharoptosis.