Factors affecting the hypotensive effect of selective laser trabeculoplasty in primary open-angle glaucoma

Abstract

This study analyzes the influence of various factors on the hypotensive effect of selective laser trabeculoplasty (SLT) in patients with primary open-angle glaucoma (POAG). A retrospective study of the SLT effect was performed in 582 patients (756 eyes; mean age - 71.9±9.5 years) with POAG stages I-III. The level of intraocular pressure (IOP) decrease was assessed at 1 day, 1, 3, 6, and 12 months after SLT. The relationship between the hypotensive effect and age, gender, glaucoma stage, initial IOP level, number and type of instilled drugs, presence of intraocular lenses, and the surgeon performing the intervention were analyzed. In the entire sample, the hypotensive effect of SLT after 1 day was 4.1±3.4 mm Hg, after 1, 3, 6, and 12 months - 3.7±4.8; 3.5±3.8; 3.1±3.4 and 2.3±3.8 mm Hg, respectively. The hypotensive effect of SLT was most dependent on the preoperative IOP level (R>0.64, p<0.05). No significant correlation was found between the hypotensive effect and the stage of POAG, gender, age, number of hypotensive drugs, phakia/aphakia, and the surgeon. A weaker hypotensive effect of SLT was found in eyes receiving monotherapy with α2-adrenoceptor agonists (p<0.03) and a combination of four drugs (p<0.02). SLT is an effective method of additional IOP reduction in POAG at any stage and with any hypotensive regimen. At the same time, the results of its use in real clinical practice indicate the need for more careful IOP control after the procedure, especially in eyes with POAG stage III, as well as in eyes without hypotensive therapy and on the maximum drop regimen.