Research recently published in Microvascular Research investigated three-dimensional choroidal characteristics in different stages of diabetic retinopathy (DR) and determined the effect of panretinal photocoagulation (PRP) by using UWF SS-OCTA.

192 treatment-naïve DR patients, 42 PRP-treated DR patients and 56 healthy controls were included in this study. Results revealed that choroidal thickness (CT), choroidal vascular and stromal volume (CVV/a and CSV/a) decreased in full range of DR (without treatment), while choroidal vascularity index (CVI) decreased only in the peripheral area. Interestingly, choroid was thinning in no-DR (NDR) and mild NPDR, followed by an increased trend in moderate and late stages of DR. Meanwhile, non-perfusion area (NPA) was positively associated with CT, CVV/a, and CSV/a in moderate and late stages of DR suggesting that increased expression of VEGF might be a significant factor in choroidal thickening. After PRP, choroidal parameters decreased while an increase of CVI in the central area was observed, suggesting that PRP treatment could contribute to the redistribution of choroidal blood flow and improve the perfusion of the macula.

A 400kHz speed swept source OCTA (Bmizar, TowardPi Medical) was used in this study to quantify choroidal changes in three-dimension. Based on AI-assisted segmentation algorithm and built-in software, comprehensive choroidal parameters, including CVI, CVV, CSV, CSI and choroidal thickness, can be analyzed on the device with high reproducibility.

This research is authored by Dr. Zhaoxia Zheng, etc. team of Prof. Xiaobing Yu from Beijing Hospital.

Link to original text：https://doi.org/10.1016/j.mvr.2025.104832