Evaluation of Automatically Quantified Foveal AvascularZone Metrics for Diagnosis of Diabetic Retinopathy UsingOptical Coherence Tomography Angiography

Investigative Ophthalmology & Visual Science

article

Yansha Lu¹  Joseph M. Simonett¹  Jie Wang¹  Miao Zhang¹  Thomas Hwang¹  Ahmed M. Hagag¹  David Huang¹  Dengwang Li²  Yali Jia¹ 

[1] Casey Eye Institute, Oregon Health & Science University;Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Biomedical Sciences, School of Physics and Electronics, Shandong Normal University;Optovue, Inc.

关键词: optical coherence tomography;    diabetic retinopathy;    microcirculation;    OCTangiography;   

DOI  :  10.1167/iovs.17-23498

学科分类：社会科学、人文和艺术（综合）

来源: Association for Research in Vision and Ophthalmology

【 摘 要 】

PURPOSE. To describe an automated algorithm to quantify the foveal avascular zone (FAZ),using optical coherence tomography angiography (OCTA), and to compare its performancefor diagnosis of diabetic retinopathy (DR) and association with best-corrected visual acuity(BCVA) to that of extrafoveal avascular area (EAA).METHODS. We obtained 3 3 3-mm macular OCTA scans in diabetic patients with various levelsof DR and healthy controls. An algorithm based on a generalized gradient vector flow (GGVF)snake model detected the FAZ, and metrics assessing FAZ size and irregularity werecalculated. We compared the automated FAZ segmentation to manual delineation and testedthe within-visit repeatability of FAZ metrics. The correlations of two conventional FAZmetrics, two novel FAZ metrics, and EAA with DR severity and BCVA, as determined by EarlyTreatment Diabetic Retinopathy Study (ETDRS) charts, were assessed.RESULTS. Sixty-six eyes from 66 diabetic patients and 19 control eyes from 19 healthyparticipants were included. The agreement between manual and automated FAZ delineationhad a Jaccard index > 0.82, and the repeatability of automated FAZ detection was excellent ineyes at all levels of DR severity. FAZ metrics that incorporated both FAZ size and shapeirregularity had the strongest correlation with clinical DR grade and BCVA. Of all the testedOCTA metrics, EAA had the greatest sensitivity in differentiating diabetic eyes without clinicalevidence of retinopathy, mild to moderate nonproliferative DR (NPDR), and severe NPDR toproliferative DR from healthy controls.CONCLUSIONS. The GGVF snake algorithm tested in this study can accurately and reliably detectthe FAZ, using OCTA data at all DR severity grades, and may be used to obtain clinically usefulinformation from OCTA data regarding macular ischemia in patients with diabetes. While FAZmetrics can provide clinically useful information regarding macular ischemia, and possiblyvisual acuity potential, EAA measurements may be a better biomarker for DR.

【 授权许可】

CC BY|CC BY-NC-ND