![]() ![]() 20, 22 - 27 Jia et al 18 recently quantified optic disc perfusion using the split-spectrum amplitude-decorrelation angiography (SSADA) algorithm on a custom swept-source OCT system and showed decreased optic disc perfusion in glaucoma. Laser Doppler flowmetry (LDF) and laser speckle flowgraphy (LSFG) have demonstrated reduced optic nerve head (ONH) and peripapillary blood flow dynamics in glaucoma. Some studies 15 - 21 have shown that glaucoma may be associated with vascular dysfunction, suggesting another possible imaging target for early diagnosis and monitoring of glaucoma. 4, 5 Structural studies 6 - 14 of retinal nerve fiber layer (NFL) by optical coherence tomography (OCT) show its promise as an objective quantifiable measure for glaucoma assessment, but it has limited sensitivity for detecting early glaucoma and only moderate correlation with VF loss. Visual field (VF) testing remains the criterion standard for glaucoma assessment, but it has substantial variability, with poor reproducibility in some patients. 1 - 3 Early diagnosis and close monitoring of glaucoma are important given the insidious onset of glaucoma, with irreversible nerve damage associated with vision loss. Glaucoma is the second leading cause of blindness worldwide, affecting more than 60 million people and predicted by 2020 to reach 79.6 million. Quantitative OCT angiography may have value in future studies to determine its potential usefulness in glaucoma evaluation. The areas under the receiver operating characteristic curve for normal vs glaucomatous eyes were 0.892 for peripapillary flow index and 0.938 for peripapillary vessel density.Ĭonclusions and Relevance Using OCT angiography, reduced peripapillary retinal perfusion in glaucomatous eyes can be visualized as focal defects and quantified as peripapillary flow index and peripapillary vessel density, with high repeatability and reproducibility. Peripapillary flow index (Pearson r = −0.808) and peripapillary vessel density (Pearson r = −0.835) were highly correlated with visual field pattern standard deviation in glaucomatous eyes ( P = .001 for both). Peripapillary flow index and peripapillary vessel density in glaucomatous eyes were lower than those in normal eyes ( P < .001 for both). In normal eyes, between-visit reproducibilities of peripapillary flow index and peripapillary vessel density were 4.3% and 2.7% of the coefficient of variation, respectively, while the population variabilities of peripapillary flow index and peripapillary vessel density were 8.2% and 3.0% of the coefficient of variation, respectively. In 12 glaucomatous eyes, this network was visibly attenuated globally and focally. Results In 12 normal eyes, a dense microvascular network around the disc was visible on OCT angiography. Correlations between vascular and visual field variables were assessed by linear regression analysis. ![]() The Mann-Whitney test was used to compare the 2 groups of eyes. Main Outcomes and Measures Variability was assessed by the coefficient of variation. The data statistical analysis was performed from October 30, 2013, to May 30, 2014. Peripapillary vessel density was the percentage area occupied by vessels. Peripapillary flow index was calculated as the mean decorrelation value in the peripapillary region, defined as a 700-µm-wide elliptical annulus around the disc. ![]() The split-spectrum amplitude-decorrelation angiography algorithm was used. The optic disc region was imaged twice using a 3 × 3-mm scan by a 70-kHz, 840-nm-wavelength spectral OCT system. In total, 12 glaucomatous eyes and 12 age-matched normal eyes were analyzed. Participants were recruited and tested at Casey Eye Institute, Oregon Health & Science University. Objective To detect peripapillary retinal perfusion in glaucomatous eyes compared with normal eyes using optical coherence tomography (OCT) angiography.ĭesign, Setting, and Participants Prospective observational study performed from July 24, 2013, to April 17, 2014. A practical method for the clinical evaluation of ocular perfusion is needed to improve glaucoma management. Importance Vascular factors may have important roles in the pathophysiology of glaucoma. Shared Decision Making and Communication.Scientific Discovery and the Future of Medicine.Health Care Economics, Insurance, Payment.Clinical Implications of Basic Neuroscience.Challenges in Clinical Electrocardiography. ![]()
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