Repeated 50 burn/180 degree argon laser trabeculoplasty.

Thirty-five repeated 50-spot/180 degree argon laser trabeculoplasties (ALT) are prospectively compared to as many first ALT's. The distribution of the treatment variables possibly affecting the results was almost identical between the two groups. The postoperative intraocular pressure decrease was statistically significant in both groups but it was significantly smaller in the re-ALT group as compared with the pressure reduction taking place in the group receiving their first ALT.