Anna Brouwer

Results Patient population A total of 372 eyes of 189 patients were included. Two of the initial 200 uveitis patients of our cohort were excluded because the OCT scan was not performed on the same day as the ERG. Seven patients were excluded because their OCT scan was performed with a different OCT device (Heidelberg). Lastly, two patients were excluded because the algorithm could not properly segment the retinal layers in their eyes, due to a severe macula pucker or CME. In five patients with a bilateral uveitis, one eye was excluded because the algorithm could not properly segment the retinal layers of one eye. There were 40 uveitis patients with a unilateral uveitis. In one of these, there was only an OCT scan available of the uveitis eye. This enabled us to investigate 39 non-uveitis eyes of patients with a unilateral uveitis. Table 1 gives an overview of the patient characteristics and diagnoses. Of the 333 uveitis eyes, 142 eyes (42.6%) had a prolonged cone b-IT. None of the non- uveitis eyes (n = 39) of patients with a unilateral uveitis had a prolonged cone b-IT. Patients with a prolonged cone b-IT were on average older (median 61.2 (IQR 51.2 – 70.1) years) compared to patients with a normal cone b-IT (median 44.8 (IQR 33.7 – 55.7) years) and patients with unilateral uveitis (median 47.1 (IQR 32.4 -56.3) years)) (p < 0.001). There was no differences based on gender (p = 0.320). Most patients had a bilateral uveitis (n = 149 (78.8 %)). A prolonged cone b-IT was equally observed in unilateral and bilateral uveitis. There were no differences between eyes with and without a prolonged cone b-IT and uveitis diagnosis (p = 0.198), or anatomical localization of uveitis (p = 0.802). Patients (n=189) Male gender, N (%) 57 (30.2) Age, median [IQR] 53.65 [39.16, 64.07] Bilateral uveitis, N (%) 149 (78.8) Diagnosis, N (%)  Unknown cause 76 (40.2)  Sarcoidosis 29 (15.3)  Chorioretinitis 27 (14.3)  Birdshot 26 (13.8)  HLA-B27 14 (7.4)  MS 7 (3.7)  Behçet 5 (2.6)  VKH 5 (2.6) Table 1: Patient characteristics Abbreviations: N = number, IQR = interquartile range, MS = multiple sclerosis, HLA B27 = human leucocyte antigen B27, VKH = Vogt- Koyanagi-Harada. 98 Chapter 4