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Uva et al. (1331) report on a small but reasonably well designed and executed study of Pneumatic Trabeculoplasty (PNT), a procedure that has come about as a result of the unexpected finding that laser in situ keratomileusis (LASIK) lowers intraocular pressure (IOP). The mechanism for such IOP lowering remains unknown. The study design, besides being prospective and randomized, also includes four baseline IOP measurements thereby minimizing the likely impact of regression to the mean which so often limits findings from such studies. One major study result is that there is greater IOP lowering with adjunctive latanoprost than with PNT when both are added to timolol. Another is that the IOP lowering effect of PNT gradually diminishes over time while the effect of latanoprost is maintained. Neither of these two findings is surprising. The authors adequately mention the limitations of the study including the small sample size of 18 subjects in both groups. Another significant shortcoming of the study is the exclusion of all subjects in whom IOP is above 20 mmHg following treatment. Thus only one of 18 subjects is left in the study at the eight-month follow-up visit in the PNT group. This methodology precludes us from knowing the full degradation of effect following PNT over the study period. Nevertheless, the study quite nicely proves that PNT is a less effective adjunctive therapy for glaucoma relative to latanoprost when both are added to timolol.