Assessment of Retinal Blood Flow in Systemic Hypertensive Patients Using Doppler Fourier-Domain Optical Coherence Tomography (FD-OCT).

Abstract

Purpose : To evaluate and compare retinal blood flow in subjects with and without systemic hypertension using Doppler Fourier-domain optical coherence tomography (FD-OCT).

Methods : Thirty eight eyes of 38 participants without evidence of eye disease consisting of 14 eyes with systemic hypertension and 24 eyes without hypertension from the AIGS study were included in this IRB-approved analysis. All subjects were scanned by Doppler FD-OCT using a standardized, circumpapillary double circular protocol which transected all major blood vessels entering/exiting the optic nerve head. Cube/volume scans and color disc photos of the optic nerve head were obtained to help in vessel identification and quantification. Scans were then imported into Doppler OCT of Retinal Circulation (DOCTORC) grading software for refining and correcting the vessel location and also to classify vessels as veins or arteries. Total retinal blood flow (TRBF) and cross-sectional areas of the veins and arteries were computed. Measurements were compared between the two groups by Mann-Whitney U test.

Results : The age of the group with systemic hypertension was (Mean ± SD) 66.93 ± 8.10 years, similar (p=0.051) to the group without hypertension 61.38 ± 9.45 years. The mean TRBF was significantly higher (p= 0.034) in eyes with hypertension 49.17 ± 11.42 (range; 29.46 - 66.70) µl/min compared to eyes without hypertension 41.65 ± 7.69 µl/min (range; 27.05 - 54.87). There was no significant difference in total cross-sectional areas of either veins or arteries between the two groups. Mean arterial pressure (MAP) was significantly higher (p=0.048) in the eyes with hypertension 99.21 ± 9.88 mm Hg compared to the eyes without hypertension 91.53 ± 7.98 mm Hg.

Conclusions : TRBF was significantly higher in the eyes of subjects with systemic hypertension compared to those without hypertension. Increased TRBF may be related to higher MAP and dysfunctional autoregulation in the hypertensive group. Doppler OCT blood flow measurements warrant further study as potentially useful parameters in the assessment of patients with hypertension.

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.