One- and two-session laser trabeculoplasty. A randomized, prospective study

Seventy-seven eyes with primary open angle glaucoma and exfoliation glaucoma were subjected to laser trabeculoplasty and followed in a prospective way. The full 360 degrees circumference was treated, but the patients were randomized in two groups: In group 1 the full treatment was given in one session, and in group 2 it was divided into two sessions one month apart. During the follow-up time of 3 to 18 (mean: 12) months both methods of treatment gave the same reduction of IOP. The only three cases with high post-operative transient pressure spike-occurred in group 1. Although this difference of course not is statistically significant it is in agreement with other studies suggesting that a two-session approach might be safer than treating the full circumference in one session. One month after the laser treatment the eyes of group 1, where the full circumference of the trabecular meshwork had been treated, showed only a slightly larger pressure reduction (not statistically significant) than the eyes of group 2 one month after treating 180 degrees of the meshwork.