Steroid-induced ptosis: case studies and histopathologic analysis

The purpose of this study was to review patients who developed ptosis after subtenon's steroid injection and to study the mechanism of steroid-induced ptosis in an animal model.

Part 1. Twenty-two patients with uveitis who had received posterior subtenon's triamcinolone acetonide injections were retrospectively reviewed. Demographics, type of uveitis, type and number of surgeries, pre and postoperative marginal reflex distance (MRD1), and clinical outcomes were evaluated. Part 2. Study of rabbit levator muscle and aponeurosis histopathology after subtenon's triamcinolone injection was performed.

Part 1. The average age was 44.6 years (range: 14-85 years) with a mean follow-up of 14 months. The most common causes of uveitis included uveitis after cataract extraction (five), pars planitis (three), multifocal choroiditis (three), and juvenile rheumatoid arthritis (three). The average time to documented onset of ptosis was 13.9 months (range: 0-49 months). In patients who received only one steroid injection, the average time to ptosis recorded was 2.7 months (range: 0-6 months). Seventeen patients underwent ptosis repair. Part 2. No ptosis was noted in the experimental and control groups. Histopathologic analysis of levator tissues revealed no significant difference in atrophy or degree of inflammation between experimental and control groups.

Ptosis following subtenon's steroid injection ranged from mild to moderate and occurred a few months after steroid injection. Prior studies of muscles and periocular tissues exposed to corticosteroids demonstrated degenerative muscle changes; our studies revealed no histopathologic changes in the levator muscle or aponeurosis.