Choroidal morphological and microvascular differences in patients with hypertensive retinopathy

PURPOSE: To investigate alterations in choroidal structure, including changes in choroidal microvasculature and thickness, in patients with hypertensive retinopathy (HR) of Grades I–III.
METHODS: This retrospective study included 110 eyes from 63 patients with HR and 56 eyes from 30 healthy controls. The mean choroidal vascularity index (CVI), choroidal stromal index (CSI), and subfoveal choroidal thickness (SFCT) were assessed using enhanced depth imaging optical coherence tomography.
RESULTS: Lower CVI and SFCT values were associated with higher HR grades (p<0.001 and p=0.001, respectively). The mean luminal area was significantly lower in both the Grade II and Grade III HR groups than in the controls (p<0.008 and p<0.001, respectively). Although the CSI was significantly higher in the Grade II and Grade III HR groups than in the controls (p<0.009 and p<0.002, respectively), the stromal area (SA) did not differ between groups. After adjusting for relevant confounders, age, axial length, and diastolic blood pressure (DBP) were determined to be negatively associated with the CVI in individuals with HR (all, p<0.05).
CONCLUSION: A lower CVI and choroidal thickness were associated with higher-grade HR; however, the SA was similar between groups. Greater HR severity can lead to more profound disruptions in choroidal structure due to the enhanced severity of choroidal microvascular damage, and elevated DBP can exacerbate damage to the choroidal microvasculature.

Keywords: Choroid, Hypertensive retinopathy, Microvasculature, Optical coherence tomography