Glaucoma patients who undergo delayed treatment may not see many visual function consequences. Photo: Brian D. Fisher, OD. Click image to enlarge.

Upon comparing the long-term visual outcomes in the two arms of the Early Manifest Glaucoma Trial to determine if delayed treatment was associated with decreased visual function, researchers recently found that vision impairment occurred at similar proportions in both treatment arms with a slight preponderance in the treatment group, while visual field damage was slightly higher in the control group.

A total of 255 subjects with newly detected, untreated glaucoma were randomized to immediate treatment with topical betaxolol and argon laser trabeculoplasty or to no initial treatment as long as no progression was detected. Subjects were followed prospectively with standard automated perimetry, visual acuity measurements and tonometry for up to 21 years.

The percentages of eyes with vision impairment or blindness were slightly higher in the treated group than in the untreated control group (12.1% vs. 11.0% and 9.4.% vs. 6.1%, respectively), as were subjects with vision impairment ≥one eye (19.5% vs. 18.7%). The differences were not statistically significant, nor were the cumulative incidences of vision impairment in at least one eye. The control group had more field loss than the treatment group, with median mean deviation in the worse eye of -14.73dB vs. -12.85dB and rate of progression of -0.74dB/year vs. -0.60dB/year, not statistically significant. Differences in visual acuity were minimal.

“These findings indicate that the cost of delaying glaucoma diagnosis, and thus treatment, a few years in patients with early glaucoma should not be associated with a large visual function penalty but probably with some smaller penalty,” the team concluded in their paper.