Purpose:
To examine the influence of pseudophakia and prostaglandin analogues (PG) on the intraocular pressure (IOP) lowering effect of selective laser trabeculoplasty (SLT).
Methods:
Retrospective chart review of patients with open angle glaucoma, who underwent SLT between 3/2008 and 12/2010 due to uncontrolled IOP despite maximum tolerated medical treatment, with a follow-up (FU) ≥3months. Data were collected before SLT, 1 day, 1 month, 3 months and then every 3 months post SLT up to 2.5 years of FU. Main outcome measures were mean IOP reduction, and success rate (≥20% IOP reduction). Repeated SLT was not considered as treatment failure.
Results:
131 eyes of 94 patients (53 female, mean age 71.8±11.23 years) were included in the analysis. Mean FU was 1.05 ± 0.67 years. Mean IOP was significantly reduced up to 1.75 years of FU (table 1). Up to 2 years of FU, patients with higher baseline IOP had greater absolute and relative reduction of IOP (R2=0.358; p=0.009 and R2=0.249; p=0.035, respectively). There was a significant negative influence of pseudophakia on absolute reduction of IOP at 9 and 12 months (p=0.049 and p=0.039) and on relative reduction at 9 months (p=0.035). There was a significant negative influence of preoperative PG treatment on relative reduction of IOP at 12 and 15 months (p=0.025 and p=0.038). There was no significant difference in survival analysis for phakic and pseudophakic patients as well as for patients with or without PG (p=0.671 and p=0.994, respectively). 12 patients had a repeated SLT (mean time to re-SLT 376.9d±204.1). 15 patients had additional IOP lowering surgery (mean time to failure 307.9d±189.2).
Conclusions:
Even in patients on maximum IOP lowering medication SLT significantly reduces IOP for up to 1.75 years, with greater IOP reduction in patients with higher preoperative IOP. IOP reduction seems to be greater in phakic patients naïve to PG treatment, although this effect is temporary.
Keywords: intraocular pressure • laser • outflow: trabecular meshwork