Use of optical coherence tomography angiography for assessment of microvascular changes in the macula and optic nerve head in hypertensive patients without hypertensive retinopathy

Abstract

PurposeTo compare optical coherence tomography angiography (OCTA) screening parameters of the macula and optic nerve head (ONH) between healthy volunteers and chronic hypertensive patients without hypertensive retinopathy. MethodsThis was an observational, cross-sectional study. Fifty-seven chronic hypertensive patients without hypertensive retinopathy (22 men and 35 women) and 40 healthy volunteers (17 men and 23 women), ranging in age from 60 to 70 years, were included in this study. Patients and volunteers were divided into three groups and one eye was selected randomly from each participant. Group A comprised patients who had a history of hypertension for >10 years (n = 35); Group B comprised patients who had a history of hypertension for 5–10 years (n = 22); and Group C comprised 40 healthy volunteers who had no history of hypertension. A 3 × 3-mm macula scan and a 4.5 × 4.5-mm ONH scan were performed in each group by OCTA using prototype AngioVue software within the AngioVue device. Vessel density (VD), foveal avascular zone (FAZ) area, choriocapillaris flow area, ONH capillary density, retinal nerve fiber layer (RNFL) thickness, and demographic information were compared among the groups. ResultsMacula scans showed that superficial plexus VD was significantly lower in groups A and B than in group C (P < 0.05). In addition, FAZ area was significantly larger in group A than in group C (P < 0.05). Inner retinal layer thickness was significantly thinner in groups A and B than in group C (P < 0.05). In ONH scans, RNFL thickness was significantly thinner in group A than in groups B and C (P < 0.05); it was significantly thinner in group B than in group C (P < 0.05). Inside disc capillary density and peripapillary capillary density were significantly lower (P < 0.05) and greater (P < 0.05), respectively, in groups A and B than in group C. ConclusionsSuperficial plexus VD, FAZ area, capillary density, and inner retinal thickness changed significantly in hypertensive patients without hypertensive retinopathy. However, only RNFL thickness was significantly thinner in patients who had >10 years of hypertension, compared to patients who had 5–10 years of hypertension. In addition, OCTA provided a method to prospectively assess changes in retinal microvasculature and thickness, thereby avoiding further long-term retinal damage in hypertensive patients.