Advantages:

Retinitis pigmentosa may be associated with macular edema and cystoid spaces. Topical dorzolamide may be useful in improving macular edema.

Methods:

Prospective evaluation of the use of dorzolamite  (topical 3 times daily for 3-6 months) in ME cases associated with RP.

Six cases with RP were identified by OCTas having macular edema. A course of dorzolamide drops was initiated 3 times/day for 3-6 months. Evaluation of visual acuity, macular thickness by OCT was performed for all patients. Mean macular thickness was 420 microns. Five cases responded by the resolution of macular edema at 6 weeks post-medication. Macular thickness improved to a mean of 220 microns with no intraretinal edema. One case rebound at 8 months and needed retreatment. One case failed medication. There was improvement of visual acuity of 2 lines in 2 patients.

Effectiveness / Safety:

Topical dorzolamide is an effective medication in macular edema associated with RP. No associated topical or systemic side effects were noted.

Take home message:

The use of topical carbonic anhydrase inhibitors should be considered in ME associated with RP. The effect is presumably related to improvement in function of outer blood ocular barrier and RPE function.