Evaluation of retinal vascular density in third trimester pregnancies by optic coherens tomography angiography

Purpose: We aimed to investigate retinal vascular density, foveal avascular zone (FAZ) and choroidal thickness in third trimester pregnant women compared with non-pregnant women. Material-Method: 40 healthy pregnant women in the third trimester and 40 healthy control groups were included in the study. Only the right eye of the patients was included in the study. Optical Coherence Tomography Angiography (OCTA) were performed at the same time of day (09: 00-12: 00) HD angio retina 6x6 mm and HD angio retina 3x3 mm scanning methods were used. Vascular density (VD) was measured in the parafovea, perifovea and the whole area of the macula in the superficial capillary plexus (SCP) and Deep Capillary Plexus (DCP). FAZ area (mm2), FAZ circumference (mm) and Foveal Density (FD) were measured automatically with the instrument software. Choroidal images were obtained with the enhanced HD line module of the OCTA device. All parameters were compared statistically and p <0.05 was considered significant. Results: The mean gestational age of the pregnant women was 34.02 week. (28-41 week). The mean age of the pregnant group was 28.80 ± 5.27 (20-38) years and the mean age of the control group was 29.23 ± 5.39 (20-38) years and the difference was not statistically significant (p = 0.732). In the pregnant group, the VD in the SCP was 55.59 ± 2.99% in parafovea, 53.44 ± 2.69% in perifovea and 52.80 ± 2.60% in whole area. In the control group, the VD in the SCP was 54.96±3.63% in parafovea, 52.59±3.46% in perifovea and 52.03±3.31% in whole area. VD in SCP was not statistically significant in any region (p> 0.05). In DCP measurements; VD in the pregnant and control group was 60.36 ± 4.36% and 58.66 ± 4.19% in parafovea, 59.18 ± 6.50% and 58.15 ± 5.60% in perifovea, 57.73 ± 6.12% and 56.54 ± 5.44% in whole area, respectively. VD in DCP was found statistically significant only in the parafovea region (p = 0.015). FAZ area was 0.33 ± 0.10 mm2 in pregnant group and 0.28 ± 0.10 mm2 in control group, FAZ circumference 2.29 ± 0.37 mm in pregnant women and 2.14 ± 0.45 mm in control group. Foveal Density was 53.52 ± 3.32% in pregnant women and 51.08 ± 3.58% in the control group. FAZ area and Foveal Density were statistically significantly higher in pregnant women (p <0.05). Subfoveal choroidal thickness was 358.13 ± 84.89 µm in pregnant women and 335.98 ± 77.12 µm in the control group. Choroid thickness was higher in pregnant women in subfoveal, but the difference was not statistically significant in subfoveal regions (p> 0.05). Conclusion: Physiological changes during pregnancy may alter the retinal vascular structures. VD in DCP was significantly higher in parafoveal area and FAZ area and foveal density also were significantly higher in pregnant women.