Background: Since the neuroretinal rim is the major parameter in the quantitative analysis of the optic nerve head, it was the purpose of the present study to measure its size and correlations in adult Chinese in a population-based setting.
Methods: The Beijing Eye Study, a population-based, cross-sectional cohort study, included 4439 subjects out of 5324 subjects invited to participate (response rate 83.4%) with an age of 40+ years. The present study included a random sample of 781 subjects with normal intraocular pressure (IOP), normal visual field and a normal optic nerve head; and a random sample of 84 subjects with an IOP > 21 mm Hg. Color optic disc photographs (30°) were morphometrically examined.
Results: In the normal group, neuroretinal rim measured 1.70 ± 0.30 mm2. It was significantly correlated with optic disc area (Rim Area = 0.43 * Disc Area + 0.67; P<0.001). It was not significantly associated with age, gender, and the known diagnosis of diabetes mellitus, arterial hypertension, arterial hypotension, hyperlipidemia, coronary heart disease, and cerebral hemorrhage. Taking the whole study group, neuroretinal rim significantly decreased with intraocular pressure (P>0.001).
Conclusions: In adult Chinese, the neuroretinal rim area measures on optic disc photographs 1.70 ± 0.30 mm2. It was statistically independent of age. Compared with data of studies from Western countries, the neuroretinal rim is larger in adult Chinese than in adult Caucasians.
- Neuroretinal rim
- Optic disc
- Peripapillary atrophy
- Refractive error
- Visual impairment