The purpose of this study was to evaluate automated measurement of the foveal avascular zone (FAZ) area using the Kanno-Saitama macro (KSM) software in Image J with swept-source optical coherence tomography angiography (SS-OCTA) images. Methods: In this cross-sectional study, one photographer scanned the macular area (3 3 3 mm) of healthy volunteers twice on the same day, at the same time. The FAZ area was measured from the en face image of the superficial retinal layer by two masked examiners, using the KSM and the Advanced Retina Imaging (ARI)-network method in Carl Zeiss online analysis. Intra-and interscan reproducibility and FAZ area were compared among the methods. Results: Forty eyes of 22 healthy volunteers were included in the analysis. The mean 6 SD age of the subjects was 34.6 6 12.4 years. Intra-and interscan intraclass coefficients ranged from 0.997 to 1.000 and 0.989 to 0.995, respectively. The mean FAZ area was 0.264 6 0.08 mm 2 by the KSM, 0.245 6 0.08 mm 2 by the ARI, and 0.281 6 0.09 mm 2 by the manual method. The mean difference between the KSM and manual methods was 0.015 mm 2 , which was significantly smaller than the mean difference between the ARI and manual methods (0.034 mm 2 ; P , 0.001). Conclusions: Automated determination of the FAZ area is feasible and yields results comparable to those obtained by manual measurement. The FAZ area measured with the KSM program is less user dependent and could potentially contribute to our understanding of the pathophysiology of various retinal diseases, particularly underlying vascular diseases. Translational Relevance: This study demonstrates a novel automated determination of the FAZ area using the Image J macro program in SS-OCTA images. This program was feasible and yields results comparable to those obtained by manual measurement.

PurposeTo evaluate the reproducibility of vessel density calculations using different binarization methods obtained via two commercially available swept-source optical coherence tomography angiography (SS-OCTA) systems.MethodsHealthy volunteers were imaged using two swept-source optical coherence tomography angiography (SS-OCTA) devices, PLEXElite and Triton. SS-OCTA examinations were performed using a 3 × 3-mm volume scan pattern centered on the fovea. A total of six methods were used for binarization in ImageJ, two global thresholding and four local adaptive thresholding methods. Resultant vessel density values were compared between the instruments and binarization methods. Images for 60 eyes from 30 healthy subjects were assessed by two reviewers who were blinded to the scanning system used.ResultsTwenty-two eyes were excluded due to poor image quality (17 eyes from Triton, 4 eyes from PLEXElite, and 1 eye from both instruments, P = 0.003). A final 38 eyes from 23 subjects were eligible for analysis. Each binarization method and instrument led to different median values. The coefficients of variation for vessel density measurements ranged from 0.3% to 2.3% and 0.6% to 4.7% for the PLEXElite and Triton, respectively. Local adaptive thresholding methods revealed higher reproducibility than did global thresholding methods for both devices.ConclusionsMacular scans with both SS-OCTA instruments showed good reproducibility for vessel density measurements. PLEXElite recorded fewer poor images and had higher reproducibility than did Triton. These findings will inform the selection of proper binarization methods for the clinical detection of vascular diseases affecting the central retina.Translational RelevanceThe reproducibility for macular vessel measurements with SS-OCTA instruments was good. PLEXElite recorded fewer poor images and had higher reproducibility than did Triton.

PurposeTo evaluate microvascular changes in the macular area of eyes with rhegmatogenous retinal detachment (RRD) without macular involvement (macula-on RRD) using swept-source optical coherence tomography angiography (SS-OCTA).Patients and methodsFive patients with macula-on RRD were eligible for analysis. All patients underwent SS-OCTA examination (Triton) for the macular area. The healthy fellow eyes were included as controls. The vessel density (VD) was calculated using binarization, and the foveal avascular zone (FAZ) was measured. The VD and FAZ area were compared between the eyes with RRD and the fellow eyes using the Wilcoxon signed rank test.ResultsThe patients’ clinical characteristics were as follows: age, 49.0 years (21.0, 54.0) (median [25, 75th percentile]); preoperative best-corrected visual acuity, −0.08 (−0.08, 0.11) for RRD and −0.08 (−0.08, −0.03) for the fellow eye (P=0.50); and axial length, 27.0 (25.1, 28.7) mm for RRD and 27.4 (25.6, 28.5) mm for the fellow eye (P=0.31). The parafoveal VD was not significantly different between the eyes with RRD and the fellow eyes (P=1.00 for the superficial retina and P=0.44 for the whole retina). The FAZ area was also similar for the eyes with RRD and the fellow eyes (P=0.31 for the superficial retina and P=0.13 for the whole retina).ConclusionThe findings of this study suggest that the macular microvasculature remains intact in eyes with macula-on RRD.

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Baseline retinochoroidal images from the macula to the periphery are presented using a montaging technique of spectral domain optical coherence tomography. The scan length is approximately three times than that provided by conventional posterior scanning and provides novel spectral domain optical coherence tomography images of normal extramacular vitreoretinal and choroidal anatomy.