The investingation of optic disc vessel density by swept source optical coherence tomography angiography

Abstract

Purpose : To investigate the values and reproducibility of optic disc vessel density (VD) measured by swept source optical coherence tomography angiography (SS-OCTA).

Methods : Healthy subjects except for refractive error were included into the study subjects. 3x3mm optic disc VD was measured twice in the same day by SS-OCTA (DRI Triton, TOPCON, Japan). En face images at superficial area were binarized and VD values and interclass correlation coefficient (ICC) were calculated. The binarization was performed by Phansalkar, Otsu, and Niblack methods, and each result was compared.

Results : Forty eight eyes of 29 cases (11 males and 18 females, averaged age 33.9±11.6 y/o) were enrolled in this study. The mean(±standard deviation) VD values were 57.1±1.9% by Phansalkar method, 43.4±2.0% by Otsu method, and 40.7±0.9% by Niblack method. The differences among these values by three methods were statistically significant (p<0.001 each, Bonferroni method). The ICCs were 0.77(0.62,0.86) (95% CI) by Phansalkar method, 0.89(0.82,0.94) by Otsu method, 0.85(0.75,0.91) by Niblack method.

Conclusions : VD vlalues were significantly different by binarization methods, and our data showed that each ICC value was considerably satisfactory.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.