Abstract
Purpose: :
Selective Laser Trabeculoplasty (SLT) is a safe and effective glaucoma treatment and is commonly done by comprehensive ophthalmologists. Theoretically SLT might be repeatable, although there is limited data to support this and no data in a community setting. The purpose of this study is to examine the IOP lowering effects of repeat SLT in two comprehensive ophthalmology practices.
Methods: :
This is a multi-office retrospective chart review of repeat SLT treatments in two comprehensive ophthalmology practices between May 2001 and May 2011 on adult patients with primary open angle glaucoma, pseudoexfoliation glaucoma or normal tension glaucoma. Repeat SLT was defined as having greater than 50% of the degrees of treatment overlapping with the original area of treatment. The amount of retreatment was at the discretion of the treating physician. All included eyes experienced IOP lowering after the initial treatment. A Student’s paired t-test was used to determine change in IOP between baseline and first follow-up visit after both initial and repeat SLT procedures. Univariate regression analysis was done to evaluate the change in IOP over the entire follow up time.
Results: :
119 eyes of 88 patients were studied. Repeat SLT was performed on average 258.23 ± 273.75 days after the initial treatment. Average follow up time after repeat SLT was 199.76 ± 148.74 days. Initial SLT procedures resulted in an average decrease in the IOP by 2.194 ± 3.774 mmHg at the first follow up visit compared to baseline, while repeat SLT yielded a significantly smaller decrease of 0.913 ± 3.69 mmHg (p=0.0019). Univariate regression analysis demonstrates a decrease in IOP of 0.00306 mmHg per day over time after initial SLT treatment (p<0.0001) and a decrease in IOP of 0.00287 mmHg per day over time after repeat SLT treatment (p<0.0001). There was no statistically significant difference between initial and repeat SLT treatments on univariate regression analysis (p>0.05).
Conclusions: :
Repeat treatment with SLT in this community setting is less effective in lowering IOP compared to initial treatment. Initial and repeat treatment has similar long-term IOP lowering effects by regression analysis.
Keywords: laser • clinical (human) or epidemiologic studies: outcomes/complications • intraocular pressure