Abstract
Purpose :
Pre-eclampsia is a pregnancy complication that is characterized by high blood pressure and damages multiple organs. As etiology is poorly understood, vasoconstriction and vascular resistance increase has been noted. Visual complications occur such as blurred vision, double vision, and sometimes blindness. The purpose of this study is to characterize qualitative and quantitative retinal microvasculature changes that can serve as a biomarkers for early detection of pre-eclamptic patients.
Methods :
Retinal Images were captures using (Cirrus HD-OCT 5000 Angioplex) images of 6x6mm superficial macular scans were obtained from 11 patients with 22 scans. The scans were captured at ~840nm wavelength.Subjects were enrolled in two groups a high severity postpartum pre-eclamptic group and a postpartum control group. Data collected included foveal avascular zone area, mean parafoveal vessel density, and average bifurcation angle. Mean vessel bifurcation angle was obtained by measuring vessel branching angles within a 1.8 mm radius around the fovea. Capillary dropout percentages in parafoveal zones of increasing radii were obtained. Example of zones 0.5 mm, 1.0mm,1.5mm, 2.0 mm, 2.5mm.The capillary dropout percentage were measured using masks of radii increasing in 0.5 mm per parafoveal zone.
Results :
Preliminary Data of 11 subjects with 22 OCTA images, analysis of the FAZ mean area of postpartum preclampsia group is 0.37mm2 (±.05mm2) postpartum control is 0.64mm2 (±.08mm2), The mean vessel bifurcation angle of pre-eclamptic group is 116.96°, control group is 81.38°. Mean Peri-foveal Vessel integrated Density in a 2.75mm radius is 917.54 for the Pre-clamptic group 365.7 for the control group, respectively (p <0.0001). Capillary dropout percentages pre-eclamptic group in parafoveal zones (0.5 mm) 2.36% (1mm) 16.33% (1.5 mm) 24.77% (2.0mm) 31.36%(2.5mm) 36.49%,The percentage for control group is (0.5 mm)7.4% (1mm) 22.6% (1.5mm) 34% (2mm) 40.8% (2.5mm) 44.67%. Both groups showed increased capillary dropout with increasing radii which can be due to an anatomical feature.
Conclusions :
Based on our preliminary Data parameters obtained from the FAZ, vessel bifurcation, and mean parafoveal vessel density can be sensitive features. These parameters could serve as early biomarkers for detection of vascular changes in patients who are susceptible to pre-eclampsia and its complications.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.