Objective: To compare quantitative OCT angiography (OCTA) parameters of macular ischemia in diabetic eyes without retinopathy with those in healthy nondiabetic controls. Design: Cross-sectional study from August 2014 through June 2017. Subjects: Thirty-nine eyes of 39 diabetic patients without clinical evidence of diabetic retinopathy and 40 eyes of 40 healthy nondiabetic subjects. Methods: Subjects underwent OCTA imaging using prototype AngioVue software (RTVue XR Avanti). Analyses of the foveal avascular zone (FAZ) and vasculature surrounding the FAZ were performed on the automatically generated en face OCTA images of the superficial and deep retinal vasculatures using vessel-based and FAZ-based metrics. Main Outcome Measures: Comparison of measurements made in the superficial and deep retinal capillary plexuses of diabetic eyes and normal eyes. Results: FAZ-based analysis revealed statistically significant differences between diabetic and normal eyes in FAZ area (superficial and deep layers), perimeter (superficial layer), major axis length (superficial layer), and minor axis layer (superficial and deep layers). Vessel-based analysis revealed statistically significant differences in the binarized flow index (superficial and deep layers), both including and excluding the FAZ area. Conclusions: Quantitative OCTA parameters reveal subclinical macular ischemia at both the superficial and deep retinal capillary plexuses in diabetic eyes that do not manifest clinical retinopathy. Vessel-based and FAZ-based metrics applied to OCTA images may serve as effective tools for screening and disease monitoring in patients with diabetes without clinical evidence of retinopathy.

The purpose of this review is to summarize the current knowledge on choriocapillaris loss in advanced age macular degeneration (AMD). Several histopathological studies in animal models and human eyes had showed that the choriocapillaris density decreases with age. However, the role of choriocapillaris loss is still unclear in AMD and its advanced forms, either choroidal neovascularization (CNV) or geographic atrophy (GA). Some authors have hypothesized that choriocapillaris loss might precede overt retinal pigment epithelium atrophy. Others have hypothesized that deposition of complement complexes on and around the choriocapillaris could be related to the tissue loss observed in early AMD. The development of imaging modalities, such as optical coherence tomography angiography (OCTA), have led to a better understanding of underlying physiopathological mechanisms in AMD. OCTA showed atrophy of choriocapillaris underneath and beyond the region of photoreceptors and RPE loss, in agreement with previous histopathologic studies. The evolution of OCTA technology suggests that CNV seems to originate from regions of severe choriocapillaris alteration. Significant progress has been made in the understanding of development and progression of GA and CNV. In vivo investigation of the choriocapillaris using OCTA may lead to new insights related to underlying disease mechanisms in AMD.

Approved by the following research ethics committee: Federal University of Paraná (UFPR), 654.007. ABSTRACT Purpose:To assess the ability of spectral domain optical coherence tomography (SD-OCT) to diagnose macular changes pre-and post-cataract surgery and to identify changes in central foveal thickness (CFT) relative to age, sex, and presence of concomitant ophthalmic pathologies, for a period of 6 months post-surgery. Methods: A prospective study of patients evaluated by SD-OCT within 5 h before surgery at 7, 30, 60, 90, and 180 days post-op, with respect to CFT and presence of maculopathy. Results: Ninety-eight eyes of 98 patients were evaluated, with the following mean results: age = 71.4 years, pre-op VA = 0.27 logMAR, and final VA = 0.73 logMAR. There were 21 eyes in patients with diabetes mellitus (DM) and 10 eyes with age-related macular degeneration (AMD), three with epiretinal membrane, and four with glaucoma. Sixty eyes had no other ophthalmic-related pathologies (NOO), and had a mean pre-op CFT of 222 µm, which progressively increased up to the 60 th day post-op, reaching a mean of 227.2 µm. No pseudophakic cystoid macular edema was observed. The mean CFT was statistically significantly different (p<0.001) between NOO and diabetic patients from 30 days post-op. Four eyes presented with preoperative diagnosis of AMD as measured by ophthalmoscopy. After completion of the OCT, which was performed within 5 h before surgery, six additional patients were found to have AMD. Of the 98 total eyes, 10 were diagnosed with maculopathy only by OCT exam. Binocular indirect ophthalmoscopy (BIO) was unable to detect such changes. Conclusion: OCT diagnosed preoperative maculopathies in 21.4% of the patients, and was more effective than BIO (11.2%). OCT showed a progressive increase in CFT in diabetics up to 180 days post-operatively, as well as greater CFT in male patients and patients older than 70 years.

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receives research support from Carl Zeiss Meditec, Topcon, and OptoVue. Nadia K. Waheed is a consultant for Optovue, and receives research support from Carl Zeiss Meditec and Topcon. There are no conflicting relationships for any other author. Purpose A) to assess the variability in vessel density (VD) measurements across three OCTA devices B) to identify a method that offers the least amount of variation in VD 3