She suffered from Sjogren syndrome and inflammatory arthritis and was currently treated with prednisone and methotrexate. She was previously treated with hydroxychloroquine (Plaquenil) 200mg bid (6.5mg/kg) for 10 years, which was stopped one year prior to presentation. Can plaquenil make you tired Plaquenil dilated eye retinal exam Plaquenil and iron Plaquenil methotrexate interactions Abstract Introduction Multifocal electroretinography mfERG is a new technique that allows analysis of local function of Retina. Hydroxychloroquine is a drug which has dose dependent systemic toxicity including significant visual disturbances & loss of vision. The use of mfERG for evaluating Determination of hydroxychloroquine toxicity Plaquenil toxicity. In general, an abnormal mfERG indicates that the foveal cones and/or bipolar cell layers are dysfunctional and the source of vision loss. Unlike the focal ERG, mfERG also indicates the precise distribution of the retinal dysfunction. And quantified using ERG. Which type of ERG to apply depends on the mechanism and site of retinal toxic-ity. Identifying retinal toxicity due to chloroquine or hydroxychloroquine is a pertinent application of mfERG. SIGNS OF TOXICITY Plaquenil toxicity first affects small areas of the retina between 5° and 15° from the fovea. Figures 2 and 3 show Review of systems: Blurred vision, halos, dry eye, dry mouth, gastroesophageal reflux, joint pain Pupils: Reactive to light in each eye from 5 mm in the dark to 2 mm in the light. Extraocular movements: Full, both eyes (OU) Confrontation visual fields: Full OU Intra-ocular pressure The optic nerves appeared healthy with a 0.3 cup-to-disc ratio. Past Ocular History: None Medical History: Sjogren syndrome and inflammatory arthritis, supraventricular tachycardia, anxiety, depression, peptic ulcer disease Medications: prednisone, methotrexate, amitriptyline, ranitidine, estradiol, tizanidine, diltiazem, Restasis Allergies: codeine, droperidol Family History: heart disease, arthritis, cancer Social History: occasional alcohol but no tobacco or intravenous drug use. Multifocal erg plaquenil toxicity Multimodal Imaging in Plaquenil Toxicity, Multifocal ERG in Practice - Ra plaquenil Multifocal ERG ring ratios reveal retinal toxicity in a surprisingly large fraction of patients taking hydroxychloroquine who are referred for evaluation and have no previous history of eye disease. We find the use of ring ratios to be a sensitive measure of dysfunction in ocular hydroxychloroquine toxicity. Detection of Early Hydroxychloroquine Retinal Toxicity.. Evaluating Hydroxychloroquine Toxicity With Multifocal.. Multifocal ERG Guiding Therapy in a Case of.. Multifocal ERG has the potential to be used as an early screening device for patients taking high doses of hydroxychloroquine before they become symptomatic or show clinical signs of toxicity. Because stabilization and perhaps reversibility are more likely if retinopathy is detected early, the development of multifocal ERG for detection of the earliest stages of hydroxychloroquine retinopathy is paramount. 15 Multifocal ERG ring ratios provide a sensitive and objective method to detect ocular toxicity in patients taking hydroxychloroquine Plaquenil. In order to measure ring ratios, the average mfERG amplitude was calculated for each of five concentric rings of a 61-hexagon mfERG. Hydroxychloroquine Plaquenil and chloroquine cause ocular toxicity, including the cornea, ciliary body, and retina. Chloroquine can cause cataract; however, no reports of hydroxychloroquine and cataract have been reported.