The comparative study of selective laser trabeculoplasty effectiveness in phacic and pseudophacic patients with glaucoma

Purpose: To compare the effect of selective laser trabeculoplasty (SLT) in phacic and pseudophacic patients with glaucoma.

Methods: A retrospective chart review was performed on 148 eyes of 139 patients with moderate primary open angle glaucoma (POAG). In the first group (pseudophacic group) 50 patients (50 eyes) underwent SLT at the period of 6 months and more after uneventful phacoemulsification cataract surgery, in the second (phacic group: 9 patients, 98 eyes) — 2‑3 months prior it. The post-laser follow up examinations were carried out at 1 day, 1 week, 1 month, 6 months and 12 months of follow-up. Average intraocular pressure (IOP), its decrease, and MD — mean deviation perimetric index — for phakic and pseudophakic eyes were compared statistically at each time period. A t-test was used to compare the IOP reduction between the phakic and pseudophakic groups.

Results: IOP reduction in the pseudophakic group was statistically significant in the 1 month of follow up (from 28.3 mm Hg to 18.6
mm Hg, p = 0.02), while in the phacic group its reduction was statistically significant in all steps of observation. The statistically significant
difference of IOP decrease level between groups was obtained in 1 week and 1 year after SLT. The MD perimetric index decreased by 3.89 dB (from –7.63 to –11.52) in the pseudophakic group and increased by 0.65 dB (from –4.31 to –3.66) in the phakic group.

Conclusion: SLT is a safe and effective means of IOP reduction in pseudophakic glaucoma patients. However it seems to be more effective in lowering IOP if performed prior to cataract surgery: effect of SLT in pseudophakic eyes reduced through 6 months. SLT performed on phakic eyes might play a role in visual field improvement.

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