This study examined whether the information provided by the Regan low-contrast letter charts on older patients is similar to that provided by conventional contrast sensitivity testing. Measurements were carried out on older adults in good eye health; older adults with early, nonexudative age-related macular degeneration (AMD); and young adults in good eye health. Agreeing with earlier work, patients in both older groups exhibited deficits in the CSF, showing sensitivity losses which increased with increasing spatial frequency. On the Regan charts, older adults in good eye health exhibited about a 1-2 line loss in acuity at all contrast levels (12-100%). AMD patients tended to have more severe losses, exhibiting their greatest deficits on the charts of high, not low, contast. For older adults in both groups, there was a statistically significant yet low correlation between contrast sensitivity at all tested spatial frequencies and Regan chart performance. In addition, most older patients who were identified as having seriously impaired contrast sensitivity also were identified as having deficient Regan chart performance. The Regan charts appear to be a reasonable alternative to conventional contrast sensitivity testing in older adults. Further analyses using regression techniques indicated that for this older adult population, predictions about contrast sensitivity problems based on high-contrast acuity were not significantly improved by measuring low-contrast acuity, except at low spatial frequencies. Results imply that a finding of greater acuity loss at low contrast than at high contrast in an older patient with good eye health may be indicative of a neuro-ophthalmological disorder, rather than ''aging'' per se.
