The medium and long-term efficacy of primary argon laser trabeculoplasty in avoiding topical medication in open angle glaucoma.

PURPOSE: To study the medium and long-term efficacy of primary argon laser trabeculoplasty in open angle glaucoma with especial emphasis on avoidance of additional medical therapy.
METHODS: Records of 168 patients with chronic open angle glaucoma or pseudoexfoliation glaucoma who underwent primary argon laser trabeculoplasty between 1987 and 1995 were studied retrospectively (duration of follow-up 1-8 years, mean 4.1 years). Mean baseline intraocular pressure was 28.7 mmHg (range 22-60 mmHg). Need of additional medical therapy was in each case evaluated at the surgeons' discretion, and the results were analysed by survival analysis.
RESULTS: The probability of treatment success (no medication required) was for chronic open angle glaucoma 77% after 2 years, 67% after 5 years and 67% after 8 years Corresponding numbers for pseudoexfoliation glaucoma were 80%, 54% and 36%. Prelaser IOP higher than 31 mmHg, pretreatment visual field defect and sparse pigmentation of the trabecular meshwork were independent predictors of failure.
CONCLUSION: Primary argon laser trabeculoplasty gives a long-lasting and favourable effect in chronic open angle glaucoma where 2/3 of the eyes still managed without additional medication for 8 years. The success in pseudoexfoliation glaucoma was even higher the first 3 years, and kept above 50% for 5 years. This makes laser a valuable option as first choice of therapy in glaucoma.