1 Identifying characteristic features of the retinal and choroidal vasculature in Choroideremia 2 using optical coherence tomography angiography 3 Running head: Choroideremia and OCTA 4 Alessandro Abbouda MD1-2, Adam M Dubis PhD1-2, Andrew R Webster1-2 MD FRCOpth, 5 Mariya Moosajee1-2 PhD FRCOpth 6 1 UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL 7 2 Moorfields Eye Hospital NHS Foundation Trust, 162 City Road, London EC1V 2PD 8 Financial Support: National Institute of Health Research (NIHR), Choroideremia Research Inc, USA 9 Foundation 10 Conflict of Interest: No conflicting relationship exists for any author 11 Corresponding Author: 12 Dr. Mariya Moosajee 13 UCL Institute of Ophthalmology, 14 11-43 Bath Street, 15 London, UK, EC1V 9EL 16 Email:
[email protected] 1 17 Abstract 18 Aims: Using optical coherence tomography angiography (OCTA) to investigate the area with 19 flow in the superficial retinal vessel network (SVRN) and choriocapillaris (CC) layer 20 amongst male subjects with Choroideremia (CHM), female carriers and normal controls to 21 identify vascular changes. 22 Methods: Images of SRVN and CC layer were acquired in 9 affected males, 5 female 23 carriers and 14 age- and gender-matched controls using the Angiovue software of the RTVue 24 XR Avanti (Optovue, Inc., Fremont, CA). 25 Results: The mean age was 33 years for affected male CHM patients (median 30 years), 46 26 years for female carriers (median 53 years) and 39 years for controls (median 38.5). Mean 27 SRVN area ± SD in subjects with CHM was 12.93±2.06 mm2 in carrier subjects, 15.36±0.60 28 mm2 and in controls 15.30±1.35 mm2 (p<0.01).