Age differences in Vistech near contrast sensitivity.

Contrast sensitivity was measured at near using the Vistech 6000 Contrast Test System (VCTS) in 287 persons aged 4 to 87 years. Obtained data compared well with those previously reported for the Vistech charts. Results indicate an age-related loss in sensitivity to intermediate and higher spatial frequencies. This is consistent with the age trends observed using other methods for measuring contrast sensitivity functions (CSFs). However, the Vistech charts yield contrast sensitivity values which are lower than those obtained previously with the Nicolet system. These between-method differences are greatest at lower spatial frequencies, and are attributed to the small number of grating cycles in the Vistech charts. The data are used to develop provisional age norms for the Vistech charts which allow the assessment of an individual's performance relative to their age cohort. Recommendations for use and future development of the Vistech charts are also given.