The Keith-Wagener-Barker (KWB) classification is used worldwide as an index of hypertensive vascular changes; however, it is a subjective evaluation classification method used by ophthalmologists and has low reliability and reproducibility. In this study, we devised a method to objectively evaluate hypertensive changes as numerical values by measuring blood flow in the choriocapillaris. Choriocapillaris blood flow in the fovea centralis of the macula region (3 mm×3 mm) in 361 healthy subjects and 206 patients with hypertension were measured with optical coherence tomography angiography(OCTA), and vessel density, vessel length, and vessel diameter were calculated using analysis software. As a significant difference was noted when comparing the right and left eyes in normal persons, we examined the factors that affected the right eye of 308 normal persons (i. e., sex, age, intraocular pressure, ocular axis), and the vessel density of the 1 mm×1 mm fovea centralis area was only slightly negatively correlated with age. Finally, comparison of 159 healthy subjects and the KWB classification I group (35 persons), II group (12 persons) revealed that the vessel density and vessel length of the 1 mm×1 mm fovea centralis area significantly decreased with hypertensive changes, and the vessel density and vessel length in multiple regression analysis showed a significant correlation only with the KWB classification; furthermore, no correlation with other items (i. e., sex, age, body mass index, blood pressure at screening, visual acuity, intraocular pressure, eye axis, oral medication) was noted. These findings suggest that measurement of choriocapillaris blood flow in the fovea centralis by OCTA may be an objective index of hypertensive changes.
Nippon Ganka Gakkai Zasshi (J Jpn Ophthalmol Soc) 124: 886-895, 2020.