Age-related changes of defocus-specific contrast sensitivity in healthy subjects.
To investigate the effect of defocus on contrast sensitivity as a function of age in healthy subjects, the through focus contrast sensitivity was measured in 100 healthy subjects aged 20-69. Defocus-specific changes in contrast sensitivity reflect age-related changes in the optics of the eye. Tests were performed in cycloplegic eyes varying artificial pupil size (2, 4 and 6 mm), defocus (-1 to +2 D), and spatial frequency (1-16 cpd). Integrated contrast sensitivity was taken as a measure for the total amount of visual information transferred by the optical media. At optimal focus, integrated contrast sensitivity and log contrast sensitivity at 8 cpd showed a significant age-related decline. The log contrast sensitivity at 1 cpd appeared to be independent of age. The depth of focus for a 4-mm pupil increased significantly with age, even though contrast sensitivity at +2 D defocus decreases with age too, but not as much as the contrast sensitivity at optimal focus. Our study indicates that the effect of defocus on contrast sensitivity decreases with age; this was attributed to age-related changes in the optical media.
Nio
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YK
Laboratory of Experimental Ophthalmology, University of Groningen, The Netherlands.
Jansonius
N M
NM
Fidler
V
V
Geraghty
E
E
Norrby
S
S
Kooijman
A C
AC
D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D015350:Contrast Sensitivity / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D008875:Middle Aged; D009184:Mydriatics / Q000008:administration & dosage; D011680:Pupil / Q000187:drug effects
D009184:Mydriatics