Abstract
Abstract: :
Purpose: The purpose of this study was to determine if the multifocal ERG (MERG) might be of diagnostic importance in evaluating asymptomatic and otherwise visually normal patients taking hydroxychloroquine. Method: The MERG was evaluated in 5 (10 eyes) visually asymptomatic patients taking hydroxychlorloquine in doses ranging from 200mg to 400mg daily for 2 to 7 years. All were taking it for rheumatoid arthritis. Ages ranged from 62 to 76 and all were female. Visual acuity, central fields and color plates (Ishihara) remained stable during the course of therapy. Examination of all fundi revealed no pigmentary changes associated with hydroxychloroquine retinopathy. Patients received standard flash ERG (ISCEV protocol) testing and multifocal ERG evaluation using the VERIS Clinic 4.2. Results: All patients had normal flash ERGs. However, each of the twelve eyes studied had markedly reduced or non-recordable MERG. Conclusion: The significance of these findings are that the MERG may detect macular changes prior to any change in visual fields, color vision, fundus or acuity in patients taking hydroxychloroquine. The MERG may prove to have application to other macular diseases before symptoms or physical findings develop and may be useful in early detection.
Keywords: 395 electroretinography: clinical • 554 retina • 355 clinical (human) or epidemiologic studies: risk factor assessment