Contact Lens Induce Blepharoptosis Through Fibrosis of Müller's Muscle.

Objective: The aim of this study was to observe and analyze the histologic characteristics and changes of the upper eyelid regarding blepharoptosis induced by wearing contact lens.

Methods: The levator aponeurosis-Müller's muscle complex specimens from 12 people who wear contact lenses were stained with hematoxylin-eosinand, Masson trichrome and antismooth muscle actin antibodies, and then were observed under light microscopy. The upper eyelids from 6 cadaver specimens were used as controls, and were examined with the same histologic techniques.

Results: Twelve people were all women aged from 34 to 51 years and the span of wearing contact lenses ranged from 8 to 21 years. The spherical equivalent refractive error of the operated eye was from 4.32 to 11.92 diopters. Müller's muscle fibrosis and decrease were identified in the contact lens group. In the control group, Müller's muscle was continuous and homogeneous.

Conclusions: In this study, the authors analyzed the upper eyelids of long-term contact lens wearing and normal people, and found that Müller's muscle fibrosis in the upper eyelids of long-term contact lens wearing patients was more obvious. The authors initially believed that long-term contact lens wearing may cause acquired ptosis by causing Müller's muscle fibrosis.