Effects of age on peripheral ocular aberrations.
نویسندگان
چکیده
On-axis monochromatic higher-order aberrations increase with age. Few studies have been made of peripheral refraction along the horizontal meridian of older eyes, and none of their off-axis higher-order aberrations. We measured wave aberrations over the central 42 degrees x32 degrees visual field for a 5mm pupil in 10 young and 7 older emmetropes. Patterns of peripheral refraction were similar in the two groups. Coma increased linearly with field angle at a significantly higher rate in older than in young emmetropes (-0.018+/-0.007 versus -0.006+/-0.002 microm/deg). Spherical aberrationC40was almost constant over the measured field in both age groups and mean values across the field were significantly higher in older than in young emmetropes (+0.08+/-0.05 versus +0.02+/-0.04 microm). Total root-mean-square and higher-order aberrations increased more rapidly with field angle in the older emmetropes. However, the limits to monochromatic peripheral retinal image quality are largely determined by the second-order aberrations, which do not change markedly with age, and under normal conditions the relative importance of the increased higher-order aberrations in older eyes is lessened by the reduction in pupil diameter with age. Therefore it is unlikely that peripheral visual performance deficits observed in normal older individuals are primarily attributable to the increased impact of higher-order aberration.
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ورودعنوان ژورنال:
- Optics express
دوره 18 6 شماره
صفحات -
تاریخ انتشار 2010