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Role of the crystalline lens in the spatial vision loss of the elderly.

This study examined the contribution of the crystalline lens to the spatial contrast sensitivity loss experienced by many healthy older adults. Spatial contrast sensitivity was measured in three groups of adults: older adults who had undergone cataract extraction and intraocular lens (IOL) insertion; older adults who were in good ocular health (agematched to the first group); and young adults also in good ocular health. Older adults had decreased contrast sensitivity at higher spatial frequencies compared to young adults, agreeing with earlier reports. In addition, both groups of older adults had similar contrast sensitivity at higher frequencies, contrary to what would be expected if the aged, noncataractous crystalline lens significantly hampered contrast transfer in the healthy older eye. Results imply that the crystalline lens is not primarily responsible for the spatial sensitivity loss of healthy older adults. Furthermore, these data indicate that for at least some IOL patients, spatial vision can be restored to a level similar to their agemates who have no history of lens opacity or ocular disease.