Relationship of retinal vascular tortuosity with the neuroretinal rim: the singapore malay eye study.

PURPOSE. To describe the association of retinal vascular tortuosity, measured quantitatively, with the neuroretinal rim. METHODS. A population-based, cross-sectional study was conducted in Malay persons aged 40 to 80 years residing in Singapore. Retinal vascular tortuosity was quantified by using a semiautomated, computer-assisted program assessing retinal fundus photographs, according to a standardized protocol. Optic disc measurements including disc area, rim area, and rim-to-disc area (RDA) ratio were obtained with a confocal scanning laser ophthalmoscope. RESULTS. In analyses adjusting for age, sex, spherical equivalent, and retinal vascular caliber, reduced arteriolar and venular tortuosity were associated with a decrease in global RDA ratio (P = 0.006 and P = 0.001, respectively). When compared with the arterioles, retinal venular tortuosity demonstrated a stronger association with RDA ratio. The temporal-inferior region of the neuroretinal rim was most strongly associated with retinal vascular tortuosity. CONCLUSIONS. Straighter retinal vessels were significantly associated with a thinning neuroretinal rim. These findings may provide additional insights into the geometric retinal vascular changes seen in early glaucomatous optic neuropathy.