Optical coherence tomography angiography findings in patients with essential hypertension

Purpose: To study the variation of retinal and choroidal density in patients with essential hypertension using Swept Source Optical Coherence Tomography Angiography (SS‐OCT A). Methods: Prospective cross‐sectional study carried out at the Ophthalmology department of Habib Thameur University Hospital of Tunis between June, 1st 2021 and March, 30th 2022. Fifteen volunteer healthy patients (30 eyes) were included. All patients underwent complete ophthalmic examination, measurements of resting systolic and diastolic blood pressure and 3 × 3 and 4.5 × 4.5 SS‐OCT A angiograms in both eyes. Perimeter of avascular central zone (ACZ), superficial retinal plexus density (SRPD), deep retinal plexus density (DRPC) and choriocapillaris capillary vessel density (CVD) were calculated on exported jpg format images using the Fiji Software. Comparative Mann Whitney and Spearman tests were performed using 21.0 SPSS. Results: Eleven males and four females were eligible for the study. Mean age was 53.33 ± 9.73 years. Eight patients (53.3%) with chronic essential hypertension were compared to seven healthy volunteers (46.7%). Mean ACZ, SRPD, DRPD and CVD were respectively 2.62 ± 0.52 mm, 13.20 ± 2.10%, 17.14 ± 1.17% and 51.05 ± 0.85%. Mean systolic blood pressure was 13 ± 5 mmHg and mean diastolic blood pressure was 7.67 ± 5.16 mmHg. CVD was lower in patients with chronic hypertension than in the control group (50.59 vs 51.41, p = 0.047). There were no significant differences between hypertension group and normal group in ACZ, SRPD and DRPC measurements ( p = 0.089, p = 0.90 and p = 0.70, respectively). No correlations were found between resting blood pressure values and ACZ measurements. Conclusions: Chronic hypertension does not affect retinal vessels and capillaries quantitative parameters. However, it may alter choroidal vascular structures by decreasing choriocapillaris vessel density. Larger studies are needed to strengthen these results.