Repeatability of Optical Coherence Tomography Angiography Measurements in Patients with Retinal Vein Occlusion

Abstract

Purpose To analyze the repeatability of vessel density (VD) measurements and manual foveal avascular zone (FAZ) measurements using optical coherence tomography angiography (OCTA) in patients with retinal vein occlusion (RVO) without macular edema. Methods The study population consisted of patients with RVO and central macular thickness <300 μm. For each subject, measurements were performed twice with a 5-minute interval. The intraclass correlation coefficient (ICC) and coefficient of variation (CV) were calculated to analyze the repeatability of results obtained with the OCTA device. To identify factors related to repeatability, we performed Pearson correlation analyses based on the CV of potential factors. Results A total of 48 eyes were included in the study. The ICCs of the VDs in superficial capillary plexus (SCP) and the deep capillary plexus (DCP) were 0.748 and 0.665, respectively, and the CVs of the VDs in SCP and DCP were 9.1% and 12.6%, respectively. The ICCs associated with the FAZ of the superficial layer (SFAZ) and that of the deep layer (DFAZ) were 0.965 and 0.956, respectively, and the CV of the SFAZ and DFAZ were 8.8% and 9.7%, respectively. From Pearson correlation analyses, OCTA quality was significantly correlated with the CV of the VDs of SCP and DCP. However, there were no variables that were significantly correlated with the CV of SFAZ and DFAZ, including OCTA quality. Conclusions VD measurements in the SCP layer using OCTA exhibited good repeatability, and VD measurements in the DCP layer exhibited relatively low repeatability compared to that of SCP layer measurements in patients with RVO without macular edema after treatment with bevacizumab. Manual measurement of the FAZ area in both SCP and DCP layers resulted in good repeatability. In addition, the repeatability of VD measurements in SCP and DCP layers was correlated with OCTA image quality.

Application of ImageJ in Optical Coherence Tomography Angiography (OCT‐A): A Literature Review

“…In addition, they highlighted that the image quality affects the repeatability of the VD measurement. In contrast, manual measurement of FAZ was highly reproducible in both SCP and DCP layers [ 89 ]. Rabiolo et al investigated several OCT-A system angiocubes.…”

“…FAZ borders can be selected manually (plot all vascular endpoints) and automatically. While the manual segmentation of FAZ has demonstrated its reliability in producing consistent outcomes [ 89 , 100 ], it is not without limitations. One such disadvantage is its reliance on the operator, which introduces the potential for differences in the findings.…”

Superficial capillary plexus vessel density/deep capillary plexus vessel density ratio in healthy eyes

“…Similar concepts are signal strength or signal strength index in other devices. Previous studies found that these values affected the measurement of VD and its reliability [1,2,9,[22][23][24]. You et al [9] reported that a lower SVD and DVD were significantly associated with a lower signal strength index, and it was the strongest impact on the measured retinal VD.…”