Argon laser trabeculoplasty in open-angle glaucoma.

Argon laser trabeculoplasty (LTP) was carried out, along the whole circumference of the trabecular band (WC-LTP) in 45 eyes and along half the circumference (HC-LTP) in 20 eyes with open-angle glaucoma. A pronounced rise of the intraocular pressure (IOP) occurred in 74% of the WC-LTP eyes, usually within 6 hours. An initial IOP rise was found to occur in 64% of the HC-LTP eyes, usually within 2 hours. The maximum IOP level was similar after both techniques, but the duration of the IOP rise was significantly shorter after the HC- than after the WC-LTP. The IOP after 24 hours was at or higher than 25 mmHg in 42% of the cases after the WC-LTP and in 10% after the HC-LTP. During the follow-up for 7-38 months after the WC-LTP 22 out of 45 eyes showed failure of IOP control below 21 mmHg: the majority of failure took place within one week. An analysis by a life-table method showed that the final probability of control after 38 months was about 48%, and that the failure of control occurred in only a few eyes after the IOP had been under control for a period of 6 months. The rate of IOP control was the following day was lower than 25 mmHg. The eyes treated by the HC-LTP were followed only for a short time, but the results appeared promising. Since the HC-LTP shows less complications than the WC-LTP, the long-term results of HC-LTP need to be evaluated for possible routine use.