Selective laser trabeculoplasty (SLT) is an effective treatment for patients with ocular hypertension and open angle glaucoma, increasingly offered as a first line alternative to medication. The LiGHT study reported that 74.2% of patients initially treated with SLT maintained target intraocular pressure (IOP) off eye drops at 36 months.1 There remains though uncertainty regarding whether post-procedure anti-inflammatory medication should be routinely used, with randomized trials showing conflicting results.2-5
Chen and colleagues conducted a systematic review and meta-analysis examining the effect of anti-inflammatory treatment on efficacy of SLT. Five randomized controlled trials were identified, including a total of 235 eyes randomized to anti-inflammatory treatment and 170 eyes randomized to placebo.
Topical anti-inflammatories may not be necessary following SLT
Overall, no significant difference in the IOP lowering effect of SLT was observed between topical anti-inflammatory, steroid, and placebo groups. There was also no difference in post-procedure pain or anterior chamber inflammation. The authors concluded that topical anti-inflammatories may not be necessary following SLT as they did not affect the magnitude of IOP reduction, discomfort or visible anterior chamber inflammation.
Of the included investigations, the Steroids after Laser Trabeculoplasty (SALT) study reported a greater decrease in IOP when topical NSAIDs or steroids were given compared to placebo, however, only 85 patients were included and participants were observed for only 12 weeks following SLT. 3 other studies, which also included placebo arms and double masked design, found no difference in outcomes. The disparity in results may be related to dissimilar characteristics of patients between studies, including degree of trabecular pigmentation or severity of glaucoma, or be due to differences in laser treatment settings or treatment endpoints.
The LiGHT study employed a standardized laser treatment protocol with 100 non-overlapping shots (25 per quadrant) applied using an energy from 0.3 to 1.4 mJ. The desired treatment endpoint was fine bubble formation at the trabecular meshwork at least 50% of the time. For eyes with pigmented trabecular meshwork, treatment was commenced at 0.4 mJ and increased in 0.1 mJ steps. Anti-inflammatory eye drops were not used routinely, and topical steroids were not permitted; however, patients were provided with a bottle of topical non-steroidal anti-inflammatory eye drops to use if they had significant discomfort. The possible relationship between topical NSAIDs and IOP lowering effect of SLT was not reported in LiGHT.
The evidence to date indicates that SLT is safe to perform without routine use of topical anti-inflammatories post-procedure. In addition, the efficacy of SLT is not influenced by use of a short course of topical NSAIDs. The meta-analysis included predominantly patients of European Ancestry; however, SLT has also been reported to be safe in other populations without recourse to routine anti-inflammatory therapy.6