Selective Laser Trabeculoplasty vs. Fixed Combinations with Timolol in Practice: A Replacement Study in Primary Open Angle Glaucoma

Abstract

Objectives:To evaluate the potential of selective laser trabeculoplasty (SLT) in two arms (360˚ vs. 180˚) as a replacement for fixed combinations (FCs) with timolol in primary open angle glaucoma over 6 months.Materials and Methods:Of 40 patients in a prospective, comparative, interventional case series, 18 eyes and 22 eyes were randomized to SLT 180º and SLT 360º groups, respectively, along with 40 fellow-control eyes. FC with timolol was discontinued on the day of treatment for the eye to be operated on, while ongoing therapy was not interrupted for the contralateral eye. Eyes were examined for intraocular pressure (IOP) elevation 1 hour and 1 day after SLT. The follow-up visits were then scheduled for 1 week, 1 month, 3 months, and 6 months after, during the which the IOP of both eyes and any possible complications were evaluated.Results:There were no statistically significant differences in mean IOPs through 6 months among the groups with exception of postlaser 1 hour and postlaser 1 day (p<0.001 and p=0.010, respectively). Multiple comparison analysis showed significantly higher IOP in both SLT 180º and SLT 360º subgroups compared to their controls at postlaser 1 hour (p=0.007, p<0.001) but significantly lower IOP only in SLT 360º subgroup compared to the controls at postlaser day 1 (p=0.013).Conclusion:SLT offers promising potential as a substitute equivalent to efficacy of FCs with timolol. However, SLT 360˚ may not achieve additional IOP reduction.

Energy Dose-Response in Selective Laser Trabeculoplasty: A Review

“…Associations between energy level and IOP reduction were not examined in that study. 69 In contrast to Ozen and colleagues and Tufan and colleagues, Tawfique and colleagues compared the results of 90-degree and 360-degree SLT in 67 patients with OAG or OHT. In that study IOP reductions were not examined, but treatment survival extents between the 2 groups were reported.…”

“…Across all of the studies summarized in Table 5 , four reported on the energy range used for treatment, which varied between 0.2 and 1.4 mJ per treatment spot. 11 , 68 , 69 , 70 The mean total energy was reported in two studies as 73.6 and 90.2 mJ. 50 , 71 Another study compared the effectiveness of SLT at 90, 180 or 360 degrees to that of topical treatment, 58 while in the other seven studies the energy was applied to 360 degrees of the TM.…”

“…While IOP reduction was greater and control of IOP was more successful in the latanoprost-treated eyes at 1 month of follow-up, these differences failed to reach statistical significance at all other follow-up visits, including at 4−6 months. 69 Lai et al compared SLT and topical antiglaucoma treatment in 32 Chinese patients with POAG or OHT. IOP reduction in both groups was similar at 5 years of follow-up, but the SLT patients required significantly fewer medications for IOP reduction during follow-up.…”

“…While such comparisons are not strictly related to the energy levels applied during treatment, it is interesting to look at the different energy levels across different studies. Across all of the studies summarized in Table 5, four reported on the energy range used for treatment, which varied between 0.2 and 1.4 mJ per treatment spot 11,68–70. The mean total energy was reported in two studies as 73.6 and 90.2 mJ 50,71.…”

Selective Laser Trabeculoplasty in the Treatment of Ocular Hypertension and Open-Angle Glaucoma: Clinical Review

“…Forty fellow eyes made up the control group. At the 6-month follow-up, the study showed no statistically significant differences between groups ( p < 0.001) [ 41 ].…”