Foveal Avascular Zone in Hypertension as Measured by Optical Coherence Tomography Angiography
Purpose: To investigate the Foveal Avascular Zone (FAZ) area in patients with arterial hypertension using optical coherence tomography angiography (OCT-A).
Material and methods: The study was permormed at the School Clinic of UNIFACISA and at the Eye Care Center. It was included 21 hypertensive patients (study group) and 19 individuals without hypertension (control group). It was excluded patientes with diabetes or glaucoma. The measurement of the FAZ areas was performed by the DRI OCT-1Triton/Plus. For the quantitative variables, the results were expressed by their means and standard deviations. Qualitative variables were expressed by their absolute and relative frequencies. Student’s t-test was used to verify differences between means and Fisher’s exact test for differences between frequencies. For evaluating the correlation between the superficial and deep plexus areas, the Pearson correlation test was used. P value ≤ 0.05, rejected the null hypothesis. The research was approved by the Ethics Committee of the Medical School from Campina Grande -UNIFACISA and all individuals signed the free and informed consent form.
Results: The means of the superficial FAZ of both eyes was significantly higher in the study group (right eye 410.7 ± 160.7 μm2 - 319.1 ± 108.2 μm2 - p = 0.0433); (left eye: 405.4 ± 144.8 μm2 versus 309.4 ± 87.7 μm2- p = 0.0174). The means of the deep FAZ areas of the right and left eyes were similar between the study and control groups (right eye: 559.6 ± 253.28 μm2 versus 605.1 ± 226.8 μm2 - p = 0.5548); (left eye: 673.2 ± 170.8 μm2 versus 585.6 ± 171.2 μm2 - p = 0.1142). The relationships between the superficial and deep plexus areas of both eyes showed a weak correlation between the two plexuses. (r = 0.4734), left eye (r = 0.2287), study group - right eye: (r = 0.4374), left eye (r = 0.3580).
Conclusion: The area of superficial FAZ of the right and left eyes was significantly higher in the hypertensive patients. The deep FAZ area of both eyes, however showed similar mean areas between the study and control groups.