Efficacy of carbonic anhydrase inhibitors on cystoid macular lesions and visual acuity in patients with X-linked retinoschisis

Abstract

Purpose : To date, there is no standard treatment regimen for carbonic anhydrase inhibitors (CAIs) in X-linked retinoschisis (XLRS) patients. This is partly caused by a lack of longitudinal follow-up data as well as relatively small cohort sizes. This retrospective study aims to evaluate the efficacy of CAIs on visual acuity and cystoid macular lesions in XRLS patients in Dutch and Belgian tertiary referral centers.

Methods : Data were collected from the medical records of all participating centers of the Dutch RD5000 consortium and the Ghent University Hospital. In total, 42 patients were enrolled, which either had molecularly confirmed XLRS or an unambiguous clinical diagnosis with an X-linked disease inheritance pattern. To be included, patients had to have previous treatment with either oral CAIs (acetazolamide) or topical CAIs (brinzolamide/dorzolamide) for at least 4 consecutive weeks. We evaluated the effect of the CAI on best-corrected visual acuity (BCVA) and the central foveal thickness (CFT).

Results : The median age at the baseline visit of the patients in this cohort study was 14.7 years (Q1: 10.2, Q3: 21.7) with a median follow-up period of 4.0 years(Q1: 2.2, Q3: 5.2). During the follow-up period, 17 patients were initially treated with an oral CAI (40%), 20 with a topical CAI (48%), and 5 patients with a combination of both topical and oral CAI (12%). We observed a significant reduction of CFT for both oral (p < 0.00001) and topical CAI (p = 0.047). The visual acuity showed a significant change while on treatment with oral and topical CAI (p = 0.028 and p = 0.028, respectively). Fourteen patients (33.3%) had side effects leading to treatment discontinuation.

Conclusions : Our data may support the use of CAI for the management of cystoid macular lesions in XLRS patients with CAIs. Despite a clinically significant reduction in CFT, the change in visual acuity was modest and not of clinical significance. Nonetheless, the anatomical improvement of the central retina in these patients may be of value in an attempt to slow down disease progression, and to potentially create the optimal retinal condition prior to future administration of subretinal gene therapy

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.