Changes in choroidal vascular parameters following pan-retinal photocoagulation using swept-source optical coherence tomography
To assess the effect of pan-retinal photocoagulation (PRP) on choroidal vascular parameters in eyes with advanced diabetic retinopathy (DR).
Forty patients (65 eyes) with severe nonproliferative DR or proliferative DR who underwent PRP were included. Changes in choroidal vascular parameters were assessed at 3, 6, and 12 months after PRP by using swept-source optical coherence tomography (OCT) and OCT angiography and were compared with baseline values.
Choroidal vascularity index (CVI) significantly decreased from 66.27% ± 1.55% at baseline to 65.85% ± 1.61%, 65.77% ± 1.29%, and 65.74% ± 1.60% at 3, 6, and 12 months after PRP, respectively. The ratio of luminal area to stromal area (L/S ratio) also significantly decreased from 1.98 ± 0.15 at baseline to 1.94 ± 0.14, 1.95 ± 0.13, and 1.93 ± 0.14 at 3, 6, and 12 months after PRP, respectively. The subfoveal choroidal thickness (SFCT) similarly showed a significant decrease from 319.50 ± 56.64 μm at baseline to 299. 07 ± 51.14 μm, 294.70 ± 58.96 μm, and 280.93 ± 53.57 μm at 3, 6, and 12 months after PRP, respectively. However, the choriocapillaris vessel density in both the fovea and parafovea showed no significant differences following PRP.
Eyes with advanced DR showed a significant reduction in CVI, L/S ratio, and SFCT over 12 months after PRP treatment.
KeywordsChoroidal vascular index Diabetic retinopathy Pan-retinal photocoagulation
This work was supported by the National Research Foundation of Korea (NRF-2015R1C1A1A01054285; NRF-2019R1H1A1035593) by the Ministry of Science, Information & Communication Technology (ICT), and Future Planning.
Compliance with ethical standards
Conflict of interest
Author JT Kim declares that he has no conflict of interest. Author N Park declares that she has no conflict of interest.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the Chung-Ang University Hospital, Seoul, South Korea and with the 1964 Helsinki declaration.
Informed consent was obtained from all individual participants included in the study.
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