Color vision and contrast sensitivity tests in early diagnosis of primary open-angle glaucoma.

Color vision was examined by the Farnsworth 100 hue test in 48 eyes with ocular hypertension (OHT). Thirteen eyes had a general loss of color discrimination and 8 had a blue-yellow axis. Spatial contrast sensitivity was tested in 31 eyes with OHT by the Mentor B-VAT and was reduced in 8 of them. Temporal contrast sensitivity was explored in 40 eyes with OHT by the Flickersyst&m and showed abnormal responses in 11 eyes. According to the lack of specificity of the responses and the overlapping of the results of normal eyes and OHT eyes, those tests are not useful for classifying an individual patient. Such investigations however have the interest to show that macular mediated functions may be impaired early in glaucoma.