Mayss Al-Sheikh1, Handan Akil2, Maximilian Pfau3, SriniVas R Sadda1. 1. Doheny Image Reading Center, Doheny Eye Institute, Los Angeles, California, United States 2Department of Ophthalmology, David Geffen School of Medicine, University of California - Los Angeles, California, United States. 2. Doheny Image Reading Center, Doheny Eye Institute, Los Angeles, California, United States. 3. Doheny Image Reading Center, Doheny Eye Institute, Los Angeles, California, United States 3Department of Ophthalmology, Rheinische Friedrich-Wilhelms University of Bonn, Bonn, Germany.
Abstract
PURPOSE: We compared the area of the foveal avascular zone (FAZ) and macular capillary network density at different retinal layers using swept-source optical coherence tomography angiography (OCT-A) in normal individuals and patients with diabetic retinopathy (DR). METHODS: Images (a 3 × 3 mm cube centered on the fovea) were acquired in 40 eyes of 22 normal individuals and 28 eyes of 18 patients with varying levels of DR using a swept-source OCT-A device (central wavelength 1050 nm; A-scan-rate of 100,000 scans per second). En face images of the retinal vasculature were generated from the superficial and deep retinal layers (SRL/DRL). Quantitative analysis of the vessel density (VD) and FAZ area was performed. Vessel density was assessed as the ratio of the retinal area occupied by vessels. RESULTS: Among the DR subjects (mean age, 72 years; 61% male), 35.7% of the eyes had mild, 35.7% moderate, and 7.1% severe nonproliferative DR (NPDR), and 21.4% and proliferative DR (PDR). The mean FAZ area in patients with DR and in normal individuals was 0.518 and 0.339 mm2, respectively, for the SRL (P = 0.003), and 0.615 and 0.358 mm2, respectively, for the DRL (P < 0.001). The mean VD (ratio) at the SRL and DRL was statistically significantly lower in patients with DR (SRL, P < 0.001; DRL, P = 0.028). CONCLUSIONS: Swept-source OCT-A of the microcirculation in eyes of patients with DR can be used to quantitatively demonstrate alterations in the FAZ and VD in the SRL/DRL of the macula compared to normal eyes. Future longitudinal studies may use these metrics to evaluate changes over time or in response to treatment.
PURPOSE: We compared the area of the foveal avascular zone (FAZ) and macular capillary network density at different retinal layers using swept-source optical coherence tomography angiography (OCT-A) in normal individuals and patients with diabetic retinopathy (DR). METHODS: Images (a 3 × 3 mm cube centered on the fovea) were acquired in 40 eyes of 22 normal individuals and 28 eyes of 18 patients with varying levels of DR using a swept-source OCT-A device (central wavelength 1050 nm; A-scan-rate of 100,000 scans per second). En face images of the retinal vasculature were generated from the superficial and deep retinal layers (SRL/DRL). Quantitative analysis of the vessel density (VD) and FAZ area was performed. Vessel density was assessed as the ratio of the retinal area occupied by vessels. RESULTS: Among the DR subjects (mean age, 72 years; 61% male), 35.7% of the eyes had mild, 35.7% moderate, and 7.1% severe nonproliferative DR (NPDR), and 21.4% and proliferative DR (PDR). The mean FAZ area in patients with DR and in normal individuals was 0.518 and 0.339 mm2, respectively, for the SRL (P = 0.003), and 0.615 and 0.358 mm2, respectively, for the DRL (P < 0.001). The mean VD (ratio) at the SRL and DRL was statistically significantly lower in patients with DR (SRL, P < 0.001; DRL, P = 0.028). CONCLUSIONS: Swept-source OCT-A of the microcirculation in eyes of patients with DR can be used to quantitatively demonstrate alterations in the FAZ and VD in the SRL/DRL of the macula compared to normal eyes. Future longitudinal studies may use these metrics to evaluate changes over time or in response to treatment.
Authors: Osama A Sorour; Almyr S Sabrosa; A Yasin Alibhai; Malvika Arya; Akihiro Ishibazawa; Andre J Witkin; Caroline R Baumal; Jay S Duker; Nadia K Waheed Journal: Int Ophthalmol Date: 2019-05-22 Impact factor: 2.031
Authors: S Tammy Hsu; Hoan T Ngo; Sandra S Stinnett; Nathan L Cheung; Robert J House; Michael P Kelly; Xi Chen; Laura B Enyedi; S Grace Prakalapakorn; Miguel A Materin; Mays A El-Dairi; Glenn J Jaffe; Sharon F Freedman; Cynthia A Toth; Lejla Vajzovic Journal: Ophthalmology Date: 2019-07-15 Impact factor: 12.079