PT  - JOURNAL ARTICLE
AU  - Duriye Damla Sevgi
AU  - Adrienne W Scott
AU  - Alison Martin
AU  - Christopher Mugnaini
AU  - Shaivi Patel
AU  - Marguerite O Linz
AU  - Akosua A Nti
AU  - Jamie Reese
AU  - Justis P Ehlers
TI  - Longitudinal assessment of quantitative ultra-widefield ischaemic and vascular parameters in sickle cell retinopathy
AID  - 10.1136/bjophthalmol-2020-317241
DP  - 2022 Feb 01
TA  - British Journal of Ophthalmology
PG  - 251--255
VI  - 106
IP  - 2
4099  - http://bjo.bmj.com/content/106/2/251.short
4100  - http://bjo.bmj.com/content/106/2/251.full
SO  - Br J Ophthalmol2022 Feb 01; 106
AB  - Purpose To evaluate longitudinal quantitative ischaemic and vasculature parameters, including ischaemic index, vessel area, length and geodesic distance in sickle cell retinopathy (SCR) on ultra-widefield fluorescein angiography (UWFA).Methods Optimal UWFA images from two longitudinal timepoints of 74 eyes from 45 patients with SCR were aligned and a common region of interest was determined. A deep-learning augmented ischaemia and vascular segmentation platform was used for feature extraction. Geodesic distance maps demonstrating the shortest distance within the vascular masks from the centre of the optic disc were created. Ischaemic index, vessel area, vessel length and geodesic distance were measured. Paired t-test and linear mixed effect model analysis were performed.Results Overall, 25 (44 eyes) patients with HbSS, 14 (19 eyes) with HbSC, 6 (11 eyes) with HbSthal and other genotypes were included. Mean age was 40.1±11.0 years. Mean time interval between two UWFA studies was 23.0±15.1 months (range: 3–71.3). Mean panretinal ischaemic index increased from 10.0±7.2% to 10.9±7.3% (p<0.005). Mean rate of change in ischaemic index was 0.5±0.7% per year. Mean vessel area (p=0.020) and geodesic distance (p=0.048) decreased significantly. Multivariate analysis demonstrated baseline ischaemic index and Goldberg stage are correlated with progression.Conclusion Longitudinal ischaemic index and retinal vascular parameter measurements demonstrate statistically significant progression in SCR. The clinical significance of these relatively small magnitude changes remains unclear but may provide insights into the progression of retinal ischaemia in SCR.