Anna Brouwer

134 Chapter 6 the median CMT of all eyes was 264 µm (IQR 250 - 260). Three eyes of the sixteen eyes had diffuse CME (CMT) > 304 µm on optical coherence tomography (OCT) at some point during their follow-up. Two eyes had a longer period of hypotony which resulted in macular folds. These folds were still present at the day of the ERG. One patient had a history of a retinal detachment in his left eye (case 1) which was treated with a posterior vitrectomy with silicon oil. The oil was removed 5 years prior to the ERG recording. The ERGs of this patient were severely abnormal in both eyes, but as expected, the eye with a history of retinal detachment was more affected. We did not find an association between a type of treatment and the absence or presence of ERG abnormalities. Five patients were treated with systemic medication (adalimumab and methotrexate) at the time of ERG recording and two patients were treated with only ocular steroid droplets. One patient had no medication at the time of ERG recording. This patient showed no signs of inflammation, but had an abnormal ERG in one eye, possibly due to the effects of end-stage glaucoma. These findings are in line with our previous studies were we also found no association between type of treatment and ERG abnormalities. 1–3 The absence of such an association could be due to the small population, different treatment strategies, and heterogeneity in the population due to responders and non-responders to treatment. In our previous studies we found a strong association between an active inflammation and ERG abnormalities. 1,2 In the current series, five eyes showed some signs of active inflammation (trace of anterior chamber cells, flare range 1+ - 3+) at the time of ERG recording and all of them had an abnormal ERG. However, of the eleven eyes that had an inactive uveitis at the time of the ERG recording, five had an abnormal ERG. Although ERG abnormalities can occur early in the disease process of uveitis, 1 in the current series the disease duration was long (median 18.9 years, IQR 16.6 - 19.8). If ERG abnormalities can also be observed in patients with a short duration of uveitis in JIA, remains therefore speculative. However, we found no association between the duration of JIA uveitis and ERG abnormalities (Spearman’s correlation coefficient 1.0, p > .999). Also, no relation was found between the mean deviation on VF and ERG abnormalities (median -3.14, IQR -4.65 - -0.80, Spearman’s correlation coefficient -.392 p = 0.143). None of the patients had severe media opacities that could have influenced the ERG results. All pupils were fully dilated at the time of ERG recording and none of the eyes had posterior synechiae at the time of ERG recording. None of the patients had central band keratopathy. With this letter we hope to illustrate to electro-physicists and ophthalmologists treating JIA uveitis that the retinal function can be affected in JIA uveitis, even though