Automated quantitative OCTA measurements of uveal melanoma-treated eyes with and without radiation retinopathy after I-125 plaque therapy and of nonirradiated fellow eyes

Abstract

Objectives: To determine if commercial OCTA measurements can provide quantitative biomarkers for detection of radiation retinopathy (RR) s/p I-125 plaque brachytherapy in patients with uveal melanoma.

Methods: Retrospective review of 6 × 6 mm OCTA images of nonirradiated fellow eyes (group 1, 28 eyes), eyes without RR (group 2, 22 eyes), eyes with RR (group 3, 13 eyes). We used automated AngioVue AngioAnalytics OCTA software determinations of FAZ size, perimeter size, and 27 capillary density measurements (nine regions of each segmentation: full-thickness retina, superficial plexus, deep plexus).

Results: Average time since irradiation was 1.9 years in group 2, and 3.7 years in group 3. FAZ size was 1.2 mm in group 3 compared with 0.2 mm in group 1 and 0.3 mm in group 2 (both p < 0.001). Capillary density was statistically significantly reduced in group 3 compared with group 1 in all 27 regions. Group 2 had significantly decreased superficial plexus capillary density compared with group 1 in three regions. Group 3 had significantly reduced capillary density compared with group 2 in 6/27 (22%) regions. Linear regression showed a change in whole-scan density of -1.5 per year after irradiation in the full-thickness retina segmentation (p = 0.008).

Conclusion: Quantitative OCTA may aid in early detection of RR.

Fig. 1. Linear regression of the FAZ size over time (number of years since irradiation).

The FAZ increases by 0.087 mm per year (p = 0.07) after I-125 plaque brachytherapy.

Fig. 2. Linear regression of capillary density of the whole-scan full-thickness retina over time (number of years since irradiation).

The capillary density decreases by −1.50 per year (p = 0.008) after I-125 plaque brachytherapy.