Additionally, another exception occurred while executing the custom error page for the first exception. : September 14, 2016 Chief complaint: Whirling and flashing lights A 57-year-old female presented to the Ophthalmology clinic at UIHC complaining bilateral central photopsias for the past two years. Chloroquine pharmacology How long can you stay on plaquenil Purpose To evaluate the utility of ring ratios in detecting hydroxychloroquine HCQ related retinal toxicity using the 103-hexagon multifocal electroretinogram mfERG. Design Retrospective cross-sectional study. Methods 23 patients taking HCQ were consecutively evaluated for retinal toxicity and divided into those without HCQ-non-toxic group and with documented visual field loss HCQ-toxic. Twenty patients on Plaquenil treatment were evaluated for retinal toxicity using the EOG and the mfERG. Group 1 comprises 15 patients 30 eyes with normal EOG. From these patients 11 22 eyes showed normal RRD of mfERG in area 1 and area 2. The rest four patients 8 eyes the RRD were reduced. Six months after interruption of HC, the mfERG improved in three cases. Group 2 comprises 5. Because early toxicity changes can be revealed on SD-OCT, it is prudent to perform a baseline screening of patients taking Plaquenil. Multifocal ERG has the ability to detect early macular dysfunction, so it should be included as part of baseline screening. A maximum daily dose of Plaquenil of 5.0mg/kg real weight is recommended. She was previously treated with hydroxychloroquine (Plaquenil) 200mg bid (6.5mg/kg) for 10 years, which was stopped one year prior to presentation. She suffered from Sjogren syndrome and inflammatory arthritis and was currently treated with prednisone and methotrexate. Multifocal erg plaquenil Subject Electroretinography, Assessing hydroxychloroquine toxicity by the multifocal ERG. Scarring alopecia plaquenil or hydroxychloroquine 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. The age-corrected amplitude of the central hexagon R1 and the ratios of R1 to each of the successive rings R1/R2. Using multifocal ERG ring ratios to detect and follow.. How to Succeed in Plaquenil Screenings. Advanced Multifocal ERG mfERG Diopsys. Multifocal electroretinography mfERG is highly sensitive for detecting hydroxychloroquine retinal toxicity. • Ring 2 P1 amplitude is the most sensitive mfERG parameter to detect hydroxychloroquine retinal toxicity. • Ring 2 P1 amplitude is inversely related to cumulative and daily doses of hydroxychloroquine. • The multifocal electroretinogram mfERG technique allows local ERG responses to be recorded simultaneously from many regions of the retina. As in the case of the full-field ERG, the ganglion cells contribute relatively little to the response, which originates largely from the outer retina. Electroretinography ERG In 2015, Tzekov and Madow 8 stated that birdshot chorioretinopathy BSCR is a rare form of autoimmune posterior uveitis that can affect the visual function and, if left untreated, can lead to sight-threatening complications and loss of central vision.