The effects of beta-blockers on ocular blood flow in patients with primary open angle glaucoma: a color Doppler imaging study.
OBJECTIVE
To evaluate the effects of four commonly used beta-blockers on ocular blood flow in patients with primary open angle glaucoma (POAG).


METHODS
Eighty eyes of 40 subjects with POAG were included in the study. Subjects were randomly divided into four groups given timolol maleate 0.50%, betaxolol HCl 0.50%, carteolol 1% or levobunolol 0.50% drops, applied twice daily (one drug to each group). Before beginning the treatment and at the end of the first month ocular blood flow velocity was measured using the color Doppler imaging (CDI) method. In the ophthalmic artery (OA), central retinal artery (CRA) and temporal posterior ciliary artery (TPCA) the peak systolic (PS) and end-diastolic (ED) blood flow velocities were measured and resistive index (RI) values were calculated. The results within each group were analysed using the matched paired student's t-test. The data between groups was compared with one-way analysis of variance (ANOVA) and Tukey-Kramer multiple comparison tests.


RESULTS
The timolol group showed a significant increase in RI values of TPCA. In the betaxolol group RI decreased significantly in CRA and TPCA, whereas in the carteolol group there was a significant decrease only in CRA. In the levobunolol group there was no change in any artery. CONCLUSIONS. Betaxolol seemed to have a greater vasodilator effect than carteolol, and levobunolol had no effect on the retinal and choroidal vasculature. Timolol may have some vasoconstrictive effect in the ciliary vasculature.
Department of Ophthalmology, Istanbul University, Istanbul Faculty of Medicine, Turkey. rana_yaymd@yahoo.com
R
R
Altan-Yaycioglu
G
G
Türker
S
S
Akdöl
G
G
Acunaş
B
B
Izgi
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D015784:Betaxolol / Q000627:therapeutic use; D001783:Blood Flow Velocity / Q000187:drug effects; D002354:Carteolol / Q000627:therapeutic use; D019842:Ciliary Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology; D005123:Eye / Q000098:blood supply*; D005260:Female; D005902:Glaucoma, Open-Angle / Q000188:drug therapy / Q000503:physiopathology*; D006801:Humans; D017078:Laser-Doppler Flowmetry; D002040:Levobunolol / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009880:Ophthalmic Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D009883:Ophthalmic Solutions; D012039:Regional Blood Flow / Q000187:drug effects; D012161:Retinal Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D013999:Timolol / Q000627:therapeutic use; D018615:Ultrasonography, Doppler, Color
D000319:Adrenergic beta-Antagonists; D009883:Ophthalmic Solutions; D013999:Timolol; D002354:Carteolol; D002040:Levobunolol; D015784:Betaxolol