Anna Brouwer

132 Chapter 6 Example of ERG curves of a JIA uveitis patient (black) and an ERG of a healthy control (grey). The implicit times of a-waves and b-waves of both the dark adapted and light adapted are prolonged. Amplitudes are often reduced as well. Abbreviations: ERG = electroretinogram, JIA = juvenile idiopathic arthritis, cds/m 2 = candela · seconds/squared meters, ms = milliseconds, µV = microvolts. 30 Hz Healthycontrol JIApatient 10.0 30.0 3.0 1.0 0.3 0.1 0.03 0.01 0.003 0.0003 0.001 0.0001 0 50 100 150 200 ms 50 µV 0 50 100 150 200 ms 200 µV Darkadapted Light adapted Flashstrengthincds/m 2 10.0 3.0 1.0 0.3 Flashstrengthincds/m 2 b b b b a a a a a a a a b b b b peak trough trough peak a a a a a a a a a b b b b b b b b b b b b a a a a a a b b b b b b b b b active. 3 This might indicate that the observed ERG abnormalities in these JIA patients can also improve. However, we have also observed that ERGs of uveitis patients can deteriorate over time. 3 If this can also occur in JIA uveitis, should be the subject of further studies. There are reports that retinal atrophy can occur in JIA patients, usually as the result of chronic cystoid macular edema (CME), a complication of JIA uveitis. 4,5 None of the JIA eyes had a retinal atrophy (central macular thickness (CMT) < 150 µm), but because ERG abnormalities may occur prior to retinal atrophy, we investigated the effects of CME on the ERG. We found no association between CMT and ERG abnormalities (Spearman’s correlation coefficient -.267, p = 0.317). At the time of the ERG recording,