[Micropulse 577 nm laser trabeculoplasty--a prospective pilot study]

To evaluate the efficacy of micropulse 577 nm laser trabeculoplasty.

Prospective clinical trial designed for 30 patients diagnosed with open angle glaucoma. The micropulse 577 nm laser trabeculoplasty was performed in one eye of each patient in the lower half of trabecular meshwork. The intraocular pressure was measured using two independent methods--Pascal tonometer and iCare tonometer--at baseline (before surgery), at 3 h, 24 h, 2 weeks and 1 month following the procedure. Pressure measurement results were compared between the treated and untreated eyes. Treatment was considered successful if the intraocular pressure dropped by ≥ 3 mmHg or ≥ 20% as compared to the baseline values or ≥ 20% as compared to the fellow eye.

The study was conducted on 11 patients. In the treated group, Pascal tonometry showed the mean decrease of the intraocular pressure by 1.7 mmHg (7.5%). The same value for the untreated eyes was 1.8 mmHg (8.1%). The results obtained using iCare tonometer showed the same proportions. The treatment did not lower intraocular pressure as compared to the untreated fellow eyes. There were no adverse effects. Even though it was impossible to perform the proper statistical analysis due to the small number of treated patients the study was eventually interrupted for ethical reasons, because of the failure to decrease the intraocular pressure in the treated group of 11 patients.

The treatment appeared to be safe but ineffective in the treated group. Further research is needed to modify laser parameters for the improvedefficacy and the maintained good safety profile of the procedure.