SELECTIVE AND NONSELECTIVE β-BLOCKERS IN PRIMARY OPEN ANGLE GLAUCOMA THERAPY – RESULTS OF COLOR DOPPLER SONOGRAPHY

Abstract

Background. Primary open angle glaucoma (POAG) is a syndrome of progressive optic neuropathy characterized by optic nerve head excavation and visual field defects. Poor correlation between IOP and progression of glaucoma disease sets vascular mechanism in the centre of attention. By Color Doppler sonography, quantification of blood flow changes in vessels, which supply optic nerve head, is possible. We wanted to find out whether there are changes in the circulation of central retinal artery and posterior ciliary arteries in patients with primary open angle glaucoma treated with selective or nonselective β -blockers.Methods. 44 patients (88 eyes) were divided into two groups: group 1: 22 patients (44 eyes) treated with selective β -blockers (Betaxolol 0.5%) and group 2: 22 patients (44 eyes) treated with nonselective β -blockers (Timolol 0.5%). Vascular indices (RI, PI) were measured in the central retinal artery and posterior ciliary arteries.Results. We found decreased blood flow and increased vascular indices in both groups of patients, statistically significant difference between group 1 and group 2: blood flow velocity was higher and vascular indices were lower in group 1 (Betaxolol 0.5%) compared to group 2 (Timolol 0..5%).Conclusions. Selective β -blockers (calcium channel blockers) act more vasoactively and neuroprotectively comparing to nonselective β -blockers.

Keywords

• β -blockers
• primary open angle glaucoma
• color Doppler sonography