Corneal Eccentricity in a Rural Japanese Population: The Locomotive Syndrome and Health Outcome in Aizu Cohort Study (LOHAS)

Purpose To determine normal corneal eccentricity in a rural Japanese population and to examine factors associated with eccentricity value. Methods This used data from the Locomotive Syndrome and Health Outcome in Aizu Cohort Study (LOHAS) project between 2009 and 2012. Residents of Minamiaizu and Tadami in Fukushima, Japan, who were aged 40 years or over, were invited for a comprehensive eye examination. For 1371 patients with no history of internal eye surgery, corneal eccentricity was measured using a Pentacam. Results Of 1371 people recruited to the study, 1215 (1215 eyes) met the inclusion criteria. The overall mean eccentricity was 0.46 (SD = 0.18; range, -0.85 to 0.88). Corneal eccentricity was significantly associated with age, spherical equivalent, pupil diameter, anterior chamber angle, anterior chamber volume, and central corneal thickness, but not with gender or body mass index. Conclusions In this study, the normal cornea in this Japanese population was prolate. Corneal eccentricity was likely to decrease with increasing age. Also, spherical equivalent and other anterior segment parameters had an influence on corneal eccentricity. Corneal eccentricity measurements might be helpful in the diagnosis of corneal diseases and in calculations for intraocular lens implantation and corneal refractive surgery.