Baskaran Karthikeyan, Unsbo Peter, Gustafsson Jörgen
Vision Enabling Laboratory, Section of Optometry and Vision Science, School of Natural Sciences, Linnaeus University, Kalmar, Sweden.
Optom Vis Sci. 2011 Sep;88(9):1088-98. doi: 10.1097/OPX.0b013e3182234630.
To compare peripheral lower and higher order aberrations across the horizontal (±40°) and inferior (-20°) visual fields in healthy groups of young and old emmetropes.
We have measured off-axis aberrations in the groups of 30 younger (24 ± 3 years) and 30 older (58 ± 5 years) emmetropes. The aberrations of OD were measured using the COAS-HD VR Shack-Hartmann aberrometer in 10° steps to ±40° horizontally and -20° inferiorly in the visual field. The aberrations were quantified with Zernike polynomials for a 4 mm pupil diameter. The second-order aberration coefficients were converted to their respective refraction components (M, J45, and J180). Mixed between-within subjects, analysis of variance were used to determine whether there were significant differences in the refraction and aberration components for the between-subjects variable age and the within-subjects variable eccentricity.
Peripheral refraction components were similar in both age groups. Among the higher order coefficients, horizontal coma (C3) and spherical aberration (C4) varied mostly between the groups. Coma increased linearly with eccentricity, at a more rapid rate in the older group than in the younger group. Spherical aberration was more positive in the older group compared with the younger group. Higher order root mean square increased more rapidly with eccentricity in the older group.
Like the axial higher order aberrations, the peripheral higher order aberrations of emmetropes increase with age, particularly coma and spherical aberration.
比较年轻和老年正视眼健康组水平方向(±40°)和下方(-20°)视野的周边低阶和高阶像差。
我们测量了30名年轻正视眼(24±3岁)和30名老年正视眼(58±5岁)的离轴像差。使用COAS-HD VR Shack-Hartmann像差仪,以10°步长测量右眼在水平方向±40°和下方-20°视野范围内的像差。对于4mm瞳孔直径,用Zernike多项式对像差进行量化。将二阶像差系数转换为各自的屈光分量(M、J45和J180)。采用受试者间和受试者内混合方差分析,以确定受试者间变量年龄和受试者内变量偏心率在屈光和像差分量上是否存在显著差异。
两个年龄组的周边屈光分量相似。在高阶系数中,水平彗差(C3)和球差(C4)在两组间变化最大。彗差随偏心率呈线性增加,老年组比年轻组增加速度更快。与年轻组相比,老年组的球差更正。老年组高阶均方根随偏心率增加更快。
与眼轴高阶像差一样,正视眼的周边高阶像差随年龄增加,尤其是彗差和球差。