Widefield (WF) swept-source optical coherence tomography (SS-OCT) imaging of eyes with proliferative diabetic retinopathy (PDR) revealed that the diabetic choroid appears to be abnormal throughout the macula, according to the results published in Retina.
The investigators used WF SS-OCT imaging to characterize choroidal thickness and vascularity at baseline in patients with treatment-naïve PDR and longitudinally after panretinal photocoagulation (PRP) at 1 week, 1 month, and 3 months. They also included normal eyes of control participants for comparison and used previously validated algorithms to determine mean choroidal thickness (MCT) and choroidal vascularity index (CVI) in 5 regions of 12×12 mm scans.
Overall, 20 PDR eyes of 15 patients were imaged between January and May 2018; 14 PDR eyes with high-quality scans from all 4 visits and normal eyes of 102 control participants were included in the final analyses. Baseline MCT of PDR eyes was not significantly different from that of control eyes. CVI measurements in all regions were lower in PDR eyes than control eyes (P <.001 to P =.008). Nearly all MCT measurements after PRP were significantly lower in all regions in PDR eyes than control eyes at 1 month and 3 months (P <.001 to.005), except the fovea (P =.074). After PRP, CVI measurements did not change in any region.
Limitations of the study included a small sample size, wide inherent variability in choroidal thickness, treatment of 4 eyes with 1 or 2 anti-vascular endothelial growth factor (VEGF) injections, and restriction of the study to only diabetic choroidopathy in eyes with PDR.
“After PRP, the choroidal thickness decreases outside the fovea, but the CVI remains constant, which suggests that a relative decrease in choroidal vascularity persists. These WF SS-OCT results are consistent with choroidal alterations found in histopathological reports of diabetic choroidopathy,” researchers report. “Future larger, multicenter, prospective studies are needed to validate our findings and to characterize diabetic choroidopathy in eyes with less advanced [diabetic retinopathy].”
The authors also suggested that the WP SS-OCT approach can be applied to investigate choroidal dysfunction in other retinal diseases.
Disclosure: This research was supported by grants from Carl Zeiss Meditec, Inc. Please see the original reference for a full list of disclosures.
Reference
Russell JF, Zhou H, Shi Y, et al. Longitudinal analysis of diabetic choroidopathy in proliferative diabetic retinopathy treated with panretinal photocoagulation using widefield swept source OCT. Retina. Published online November 26, 2021. doi:10.1097/IAE.0000000000003375