To analyze the effects of topical 10% N-acetylcysteine on patients with refractory filamentary keratitis. Methods

The present study included 29 eyes from 20 patients diagnosed with filamentary keratitis. We analyzed the cause of filamentary keratitis, types of treatments, symptom scores, number of filaments, fluorescein staining, degrees of remission, and recurrence of the disease. Results

A total of 19 eyes treated with filament removal, therapeutic contact lenses, topical antibiotics, topical steroids, topical 0.05% cyclosporine, artificial tears, and punctal plugs showed improvements. Topical 10% N-acetylcysteine was added to 10 patients who did not respond to the usual treatment for more than 1 month. Seven eyes showed a complete remission of disease at an average of 56.22 ± 24.52 days. Two eyes showed a partial remission with less than 1–2 fillaments. One eye stopped 10% N-acetylcysteine treatment because of an irritable sensation. Conclusions

Topical 10% N-acetylcysteine was an effective treatment for refractory filamentary keratitis.