Acquired color vision and visual field defects in patients with ocular hypertension and early glaucoma

PURPOSE To study acquired color vision and visual field defects in patients with ocular hypertension (OH) and early glaucoma. METHODS In a prospective study we evaluated 99 eyes of 56 patients with OH without visual field defects and no hereditary color deficiencies, followed up for 4 to 6 years (mean = 4.7 +/- 0.6 years). Color vision defects were studied using a special computer program for Farnsworth-Munsell 100 hue test and visual field tests were performed with Humphrey analyzer using program 30-2. Both tests were repeated every six months. RESULTS In fifty-six eyes, glaucomatous defects were observed during the follow-up period. There was a statistically significant difference in total error score (TES) between eyes that eventually developed glaucoma (157.89 +/- 31.79) and OH eyes (75.51 +/- 31.57) at the first examination (t value 12.816, p < 0.001). At the same time visual field indices were within normal limits in both groups. In the glaucomatous eyes the earliest statistical significant change in TES was identified at the first year of follow-up and was -20.62 +/- 2.75 (t value 9.08, p < 0.001) while in OH eyes was -2.11 +/- 4.36 (t value 1.1, p = 0.276). Pearson's coefficient was high in all examinations and showed a direct correlation between TES and mean deviation and corrected pattern standard deviation in both groups. CONCLUSION Quantitative analysis of color vision defects provides the possibility of follow-up and can prove a useful means for detecting early glaucomatous changes in patients with normal visual fields.