Qualitative analysis of optic nerve head peripapillary microvasculature in healthy eyes using optical coherence tomography angiography

Abstract

Primary objective: To evaluate optic nerve head microvasculature/radial peripapillary capillaries (RPCs) in healthy adult eyes using swept-source optical coherence tomography angiography

Secondary objectives: To evaluate macular microvascular network in healthy adult eyes using swept-source optical coherence tomography angiography

Design: Cross-sectional study

Participants: 224 eyes of 112 healthy adult volunteers at eye clinic of King Chulalongkorn Memorial Hospital.

Method: En face 3x3-mm OCTA at macular area, 6x6-mm OCTA at optic nerve head and high-definition horizontal lines 16-mm scans crossing the fovea and optic disc were acquired using the SS-OCTA Plex Elite 9000. To evaluate RPCs density, the images were binarized and skeletonized. En face 3x3-mm image used to evaluate both of superficial capillaries and deep capillaries foveal avascular zone(SCP-FAZ and DCP-FAZ)

Main Outcome and Measures: The radial peripapillary capillaries vessel density

Result: The RPCs vessel density was the most crowded at inferotemporal quadrant in all age groups with mean±SD vessel density of 17.99±2.00. The lightest quadrant was nasal quadrant with mean±SD vessel density of 14.20±1.82. The mean±SD of SCP-FAZ and DCP-FAZ were 0.31 ±0.1 mm2 , 0.56 ±0.22 mm2 respectively.

Conclusion: Our study gives the SS-OCT/OCTA normative database using the PLEX Elite 9000 device of RPCs density, FAZ area in healthy eyes of Thai people. This baseline database of healthy eyes may used to help for detect, early diagnosis or monitor in the pathologic eyes. Further investigation in pathologic eye is needed.