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.

Purpose To assess the physiology of the retina by electroretinography (ERG) with skin electrodes in eyes that had undergone vitrectomy with silicone oil (SO) tamponade. Design Retrospective case series. Method ERGs were recorded from eleven eyes with complex vitreoretinal disorders and from the normal fellow eyes. The affected eyes underwent pars plana vitrectomy (PPV) with SO tamponade. ERGs were recorded before and after the SO was removed. The amplitudes and implicit times of the a- and b-waves of the affected eyes were compared to those of the normal fellow eyes. In addition, the ratios of the amplitudes of the b-waves of the affected eyes to those of the fellow eyes were compared before and after the SO was removed. Results ERGs were recordable from 7 eyes (63.6%) before the SO was removed and 11 eyes (100%) after the SO was removed. The a- and b-wave amplitudes were significantly smaller in the affected eyes than those of the fellow eyes at the baseline. The b-wave amplitude before the removal of the SO was significantly and positively correlated with that after the SO removal. The ratios of the b-waves of the affected/normal fellow eye significantly increased after the SO was removed. Conclusion The results indicate that ERGs picked up by skin electrode can be used to assess the physiology of the retina in eyes with a SO tamponade. The amplitude of the b-waves of the ERGs in silicone-filled eyes can be used to predict the amplitude after the silicone is removed.

Purpose Optical coherence tomography angiography (OCTA) allows noninvasive observation of the retinal vasculature, and image analysis can be used to calculate the retinal vessel density and foveal avascular zone (FAZ) area. A previous study showed that macular vessel density and the signal strength index (SSI) of OCTA images increased significantly after cataract surgery. However, the effect of aging on OCTA analysis remains unclear. This study aimed to investigate age-related changes in macular vascularization while excluding the effects of cataracts. Patients and Methods OCTA imaging of the macula was performed in adult patients who had undergone cataract surgery between February 2018 and May 2019 and in young healthy participants between April 2017 and April 2018. Results The median (quartiles) age of the overall study population was 59.0 (27.0, 69.0) years, and no severe refractive error was observed (axial length: 24.2 ± 1.3 [mean ± SD] mm; spherical equivalent: 0.75 [−2.25, 0.00] diopter). When we investigated the relationship between macular vessel density and age after excluding the effects of cataracts, we found that the macular vessel density showed age-related changes even in the absence of the effects of the SSI. However, the FAZ area was not affected by age. Conclusion Macular vessel density decreased with age, even when the effects of cataracts were excluded. The effects of age and cataracts should be considered when designing studies and interpreting OCTA findings of the retinal vasculature.

The present report aimed to describe the macular structure’s recovery process in a case of optic disc pit maculopathy (ODP-M) with outer layer hole following pars plana vitrectomy (PPV) with juxtapapillary laser treatment (JPL). We performed repeated optical coherence tomography (OCT) examinations to evaluate the macular structural changes. An 80-year-old man presented with distorted vision and decreased visual acuity (VA) in his left eye, experienced for 1 year, prior to presentation. Fundus examination and OCT showed intraretinal fluid (IRF) in the inner and outer retinal layers. Serous retinal detachment (SRD) with an outer layer hole in the macula was also evident. The IRF was connected to the optic disc; however, the SRD was isolated. Best-corrected VA was 20/100. PPV combined with JPL was performed. Posterior vitreous detachment creation and tamponade with sulfur hexafluoride was performed. Postoperatively, the inner retinal IRF at the fovea disappeared. The outer layer hole gradually closed and had completely disappeared 1 month postoperatively. After resolution of the outer layer hole, SRD reduced gradually and disappeared 8 months postoperatively, although the macular outer retinal IRF remained. The outer retinal IRF had partially resolved by the 18th postoperative month. Macular structure was completely recovered 31 months postoperatively, with an improved VA of 20/20. In conclusion, SRD might be associated with outer retinal IRF and outer layer holes. In cases of ODP-M, outer layer holes might induce optic disc-isolated SRD.