[Tonometric response to acetazolamide in patients with retinal detachment]

Abstract

Introduction: Acetazolamide reduces intraocular pressure and stimulates absorption of subretinal fluid by the retinal pigment epithelium. Recording the intraocular pressure response to systemic acetazolamide might enable an indirect evaluation of retinal pigment epithelial carbonic anhydrase.

Methods: The intraocular pressure response to a standardized dose of intravenous acetazolamide (5mg/kg) was evaluated in a "case" group of 15 patients undergoing retinal detachment (RD) surgery and in a control group of 15 patients undergoing epiretinal membrane peeling. Intraocular pressure was measured with a handheld Perkins tonometer in a supine position before (t-2 min) and after the intravenous administration of acetazolamide (t+2 min, t+6 min, t+10 min and t+30 min). The mean variation of the intraocular pressure was compared between the two groups in the non-operated eye at each time point.

Results: A significant reduction of the intraocular pressure was observed in both groups at 2, 6 and 10 minutes (P<0.01) after the injection of acetazolamide (5mg/kg). The reduction was significantly lower in the group of patients who underwent retinal detachment surgery when compared with the group of patients in whom epiretinal membrane peeling had been performed. This difference remained significant up to 10 minutes (P<0.01 at t=2, 6 and 10 min). At t=30 min, the intraocular pressure reduction was comparable in both groups.

Discussion: The vitreous plays a fundamental role in the pathogenesis of retinal detachment via peripheral traction. However, since not all tears lead inevitably to retinal detachment, there must also be adherence factors which can prevent the latter. The response to acetazolamide differs significantly in patients undergoing retinal detachment surgery compared with patients treated with epiretinal membrane peeling. In the occurrence of retinal detachment, deficient photoreceptor adherence to the retinal pigment epithelium has been hypothesized. Further research should aim to correlate the tonometric response to acetazolamide with photoreceptor adherence.

Keywords: Acetazolamide; Acétazolamide; Anhydrase carbonique; Carbonic anhydrase; Décollement de rétine; Intraocular pressure; Retinal detachment; Retinal pigment epithelium; Tonus oculaire; Transport; Épithélium pigmentaire de la rétine.