Purpose: To compare the intraocular pressure (IOP) response of uncontrolled capsular glaucoma (CG) and primary open-angle glaucoma (POAG) to selective laser trabeculoplasty (SLT) in a prospective clinical trial.
Methods: Ten eyes often patients suffering from uncontrolled CG (CG Group) and ten eyes of ten patients with uncontrolled POAG (POAG Group) were treated with a frequency-doubled, Q-switched Nd:YAG laser (532 nm). The baseline characteristics were similar in both groups. IOP was measured before and 1 day, 1 week, 1 month and 3, 6, 9, 12, 15 and 18 months after treatment. Success was defined as IOP more than 20% lower than before treatment. Any change of hypotensive medication led to the subjects' exclusion from the study. The two groups were compared using the independent-sample t test for continuous variables and the log-rank test for survival analysis. A value of p<0.05 was considered significant.
Results: The mean follow-up was 12.0 months (SD 5.5) for the CG group and 13.5 months (SD 4.3) for POAG (n.s.). No significant difference was found between the two groups for mean pretreatment IOP (23.6 mmHg +/- 5.70 in the CG group and 22.8 mmHg +/- 2.44 in the POAG group) or for mean IOP and mean IOP reductions during the follow-up. At all follow-up visits, IOP was reduced less in the CG group than in the POAG group (24.8% +/- 11.15 vs. 27.7% +/- 9.91 at 6 months, 22.0% +/- 6.66 vs. 30.6% +/- 6.35 at 12 months, and 31.4% +/- 5.55 vs. 35.1% +/- 1.75 at 18 months), but the difference was significant only at 12 months. Kaplan-Meier survival analysis gave an 18-month success rate of 64% in the CG group and 78% in the POAG group, with no significant differences between the groups.
Conclusions: SLTis an effective procedure forlowering IOP in CG and POAG eyes, although the effect seems to last less in CG eyes.