Purpose. Contrast sensitivity is considered a more sensitive measure of visual function than Snellen acuity. We evaluate the factors that influence contrast sensitivity in emmetropes and spectacle corrected myopes. Methods. Twenty-nine patients (ages 23 to 67 years) comprising 22 emmetropic and 42 spectacle corrected myopic eyes (-10.25 to -1.5 diopters spherical equivalent) participated in the study. Contrast sensitivity was measured with both the Vistech and Vectorvision systems. Results. Vistech contrast sensitivity at high spatial frequencies was significantly greater in spectacle corrected myopes than in emmetropes (p=0.004 to 0.025). Vectorvision contrast sensitivity did not statistically differ between these two groups. Patient age and gender were significant factors in determining contrast sensitivity with the Vistech system (p=0.002 to 0.037), but not the Vectorvision system. There was no statistically significant difference in patient age or best corrected visual acuity between spectacle corrected myopes and emmetropes. Conclusions. Both gender and age-based reference ranges may need to be developed for the Vistech contrast sensitivity system; the Vectorvision system is apparently insensitive to these factors. The decreased Vistech contrast sensitivity observed in emmetropes as compared with spectacle corrected myopes may explain reductions in contrast sensitivity noted post-operatively in keratorefractive patients by mechanisms unrelated to the surgery.
|Original language||English (US)|
|Journal||Investigative Ophthalmology and Visual Science|
|State||Published - Feb 15 1996|
ASJC Scopus subject areas
- Sensory Systems
- Cellular and Molecular Neuroscience