Quantitative Analysis of Choriocapillaris Alterations in Swept-Source Optical Coherence Tomography Angiography in Diabetic Patients

Abstract

Purpose: To evaluate quantitative alterations of the choriocapillaris in swept-source optical coherence tomography angiography in diabetic patients.Methods: We included normal patients and diabetic patients with and without diabetic retinopathy (DR), excluding patients with macular edema. Angiograms in 3 • 3 mm were acquired with Plexelite 9000 swept-source optical coherence tomography angiography. Choroidal flow voids were analyzed after removal of projection artifacts. The main evaluation was the correlation between choroidal flow voids area (FVA-CC) and DR stage.Results: A total of 120 eyes of 72 patients were analyzed. There were 17 eyes from healthy subjects, 30 eyes without DR, 22 eyes with minimal nonproliferative DR, 30 eyes with moderate nonproliferative DR, 16 eyes with severe nonproliferative DR, and 5 eyes with proliferative DR (PDR). The percentage of FVA-CC for each group was, respectively,

Quantitative Analysis of Choriocapillaris Alterations in Swept-Source Optical Coherence Tomography-Angiography During Radiation Retinopathy

“…Moreover, projection artifacts, which are a common bias in OCTA interpretation, 23 were also avoided by careful subtraction of the flow signal of the SCP and DCP from the choriocapillaris angiograms using a normalization as described previously. 13 Finally, use of the Phansalkar method for choriocapillaris thresholding, as recommended in previous studies, 7,11 is still under debate, especially concerning window radius, which we set to six pixels based on intercapillary distance on a 3-mm • 3-mm angiogram. 24 This size angiogram does not include all regions subject to RR.…”

“…It has been demonstrated in diabetes that damage at the choriocapillaris level occurs before the retinal levels are affected on OCTA. [9][10][11] This implies that choriocapillaris alterations could be an early biomarker of radiation-induced damage and help predict the occurrence of RR. To this day, there are few OCTA studies on the choriocapillaris of eyes irradiated for ocular tumors.…”

Retinal Vascularization Analysis on Optical Coherence Tomography Angiography before and after Intraretinal or Subretinal Fluid Resorption in Exudative Age-Related Macular Degeneration: A Pilot Study

“…Another limitation was the management of segmentation artifacts on OCTA in cases where IRF disorganizes the retinal architecture [39]. For instance, some studies excluded patients with IRF, particularly when analyzing choriocapillaris vasculature [7,39,40]. Pigmented epithelium detachment could also have disorganized retinal segmentation on OCTA in the IRF and SRF groups and could thereby have modified the retinal vascular analyses.…”

Age-Related Macular Degeneration: New Insights in Diagnosis, Treatment, and Prevention

“…As demonstrated in diabetic macular edema, it appears that intraretinal fluid, which is associated with poorer visual prognosis in AMD, is related to worse vascular reperfusion when treated, in comparison to subretinal fluid [5]. Moreover, deep exploration inside the macular vascularization, at the choriocapillaris level, has demonstrated that the fellow-eyes in cases of unilateral neovascular AMD also showed vascular abnormalities such as nonexudative AMD (known as quiescent neovascularization, sometimes seen on invasive indocyanine green angiography), or choriocapillaris flow deficit, as already described in cases of high blood pressure or diabetes [4,6,7].…”