Purpose: Eye drops that promote mucin and moisture secretion and drugs that promote mucin production have recently became available for dry eye, and novel concepts of causes and treatment have been suggested with regard to filamentary keratitis (FK), a disease that is associated with dry eye. Therefore, we retrospectively investigated the causes and treatment for FK associated with dry eye.
Subjects and methods: Of the cases with dry eye that were being treated at the Kyoto Prefectural University Eye Institute, we investigated 53 eyes in 53 cases that were complicated with FK (mean age: 69.8 years). We examined the following: (1) dry eye diagnosis, (2) assumed mechanism of FK onset (three classifications: aqueous tear deficiency, increased friction, or combined mechanism), (3) treatments when FK was detected, and (4) treatments administered for improving FK.
Results: FK associated with dry eye was most common in cases with a definitive diagnosis of dry eye (87%), and the most common assumed mechanism was aqueous tear deficiency (74%). Regardless of the assumed mechanisms, several cases were using diquafosol sodium ophthalmic solution when FK was detected (aqueous tear deficiency: 39%, increased friction: 30%, and combined mechanism: 75%). In numerous cases of FK wherein the primary mechanism was assumed to be aqueous tear deficiency, for improving the disease, upper and lower punctal plug insertions (71%) were the most common treatment. Meanwhile, in several cases of FK wherein the primary mechanism was assumed to be increased friction, for improving the disease, the administration of rebamipide ophthalmic suspension (63%) was the most common treatment.
Conclusions: Our results suggest that the use of diquafosol sodium ophthalmic solution is a risk factor for FK onset. Moreover, it appears that punctal plugs are effective for treating FK associated with aqueous tear deficiency, whereas rebamipide ophthalmic suspension is effective for treating FK associated with increased friction.
Nippon Ganka Gakkai Zasshi (J Jpn Ophthalmol Soc) 123: 1065-1070, 2019.