Purpose:
To study the effect of acetazolamide on the visualacuity of patients with cystoid macular oedema of vascular origin.
Methods:
Retrospective case note review. Visual acuity recordedat onset was noted. All patients were treated with oral acetazolamide250 mg B.D. Visual acuity recorded at 1 month, 3 months, 6 monthsand one–year post intervention were noted. Statisticalanalysis was done using SPSS version 12.01. Paired sample–t–testwas performed on the data and a P value of <0.05 was consideredsignificant.
Results:
38 patients were included in the study of which 21were males and 17 were females. The average age of the studypopulation was 66.18 (range 30 to 91 years) Duration of treatmentwas between 3 to 6 months. Etiological classification was asfollows The improvement in the visual acuity from baseline was significantat 1, 3, 6 and 12 months following initiation of treatment witha P value of 0.013, 0.001, 0.007, 0.005 respectively.
Conclusions:
Acidification of the sub retinal space caused byacetazolamide is thought to be responsible for the increasein fluid resorption from the retina through the RPE into thechoroid. Several clinical studies have suggested that patientswith cystoid macular oedema due to retinitis pigmentosa anduveitis may react more favourably to acetazolamide treatmentthan those due to vascular causes such as diabetes and retinalvein occlusions. However, this study shows a significant improvementin the visual acuity of patients with cystoid macular oedemaof vascular aetiology on treatment with acetazolamide. The improvementwas sustained on follow up for a period of up to 12 months.
Keywords: diabetic retinopathy • drug toxicity/drug effects • macula/fovea