Session Title: Quick Fire Free Paper Session
Session Date/Time: Saturday 17/02/2018 | 11:45-13:00
Paper Time: 12:20
Venue: Ballroom II & III.
First Author: : I.Kovács HUNGARY
Co Author(s): : C. Czako G Sandor M. Ecsedy Z. Recsan H. Z. Nagy
To evaluate intrasession and between-visit reproducibility of macular non-flow area and macular vessel-density values in patients with diabetes.
Semmelweis University, Department of Ophtalmology
A total of 44 eyes of 22 diabetic patients underwent OCT angiography imaging (RTVue-XR Avanti; Optovue, Fremont, CA, USA). Central non-flow area and vessel density (VD) was examined in the central area with a radius of 3.0 mm from the foveolar center using the AngioAnalytics software. Three images were acquired in one visit and one image 1 month later. Intrasession and between-visit reproducibility were characterized by the corresponding intraclass correlation coefficient (ICC) and coefficient of variation (CV) values determined for the central non-flow area, and for vessel density in the 3.0 mm macular area and in the parafoveal ring.
There was no significant difference in the mean non-flow area between the two visits (0.30±0.11 mm2 vs. 0.31±0.11 mm2; p>0.05). Similarly, there was no significant difference in 3.0 mm vessel density (47.94±3.85% vs. 47.70±3.96%; p>0.05) and in parafoveal vessel density (49.48±4.08 vs. 49.26±4.19%; p>0.05) between the two visits. We measured excellent ICC values both in intrasession (0.96 to 0.97) and between-visit (0.91 to 0.94) comparisons of the analyzed paramaters. The intrasession CV was significantly higher in the non-flow area compared to CV values of vessel density in the 3.0 mm macular area and in the parafoveal ring (18.13% vs. 4.86% and 2.59%; p<0.05). Similarly, the between-visit CV was significantly higher in the non-flow area compared to CV values of the 3.0 mm macular area and the parafoveal ring (12.67% vs. 4.74% and 4.78%; p<0.05). There was no statistically significant difference between intrasession and between-visit CV values of the analyzed parameters (p>0.05). When analyzed FAZ area, between-visit variability of data was positively correlated with the initial area (r=0.54, p<0.001), but no correlation was found in case of retinal vessel density measured at the 3 mm area (p>0.05) or in the parafoveal ring (p>0.05).
Repeated OCT angiography measurement of macular vessel density revealed excellent repeatability, indicating that this non-invasive technology is sufficient for longitudinal assessment of microvascular complications in diabetes. Measurement of the macular non-flow area had higher variance, suggesting that this parameter is less reliable in the analysis of the vascular aspects of diabetic retinopathy and monitoring of disease progression and the effect of treatments.