Visual acuity and contrast sensitivity in the elderly

The visual acuity of the better eye in the elderly inhabitants of three communities (476 persons, aged 70 years or more) ranged from 0 to 1.4 (mean 0.7), and 12% saw less than 0.3. The logarithm of binocular contrast sensitivity ranged from 1.0 to 2.75 (n = 412, mean 2.19) in the Cambridge test and from 0.15 to 1.95 (n = 468, mean 1.48) in the Pelli-Robson test. The 72 subjects with healthy eyes had a mean visual acuity of 1.03 (range 0.5-1.4) in the better eye, and the two contrast sensitivity tests gave mean values of 2.45 and 1.69, respectively. Cortical, nuclear and mixed cataracts and macular pathology impaired both contrast sensitivity and visual acuity. The correlation between the three tests was good in the whole sample and in the different subgroups of cataract and macular changes. Individually, however, a few contradictory results were obtained. According to these results measurement of contrast sensitivity does not add much to the general information obtained in the elderly by visual acuity measurement alone, but in selected cases it may give valuable information.