Effect of Travoprost and Brinzolamide on ocular hemodynamics

Purpose: To investigate the effect of topical travoprost and brinzolamide on retrobulbar flow velocities and ocular pulse amplitude in glaucoma patients. Methods: Twenty patients with glaucoma underwent color doppler imaging of the central retinal, temporal and nasal short posterior ciliary and ophthalmic artery, as well as Pascal dynamic contour tonometry and ocular pulse amplitude (OPA) measurement at baseline without treatment (timepoint 1, T1), after 1 month of travoprost (T2) and subsequently after 3 months of travoprost and brinzolamide (T3). A multivariate model was used to evaluate the changes in retrobulbar flow velocities and OPA. Results: In the temporal posterior ciliary artery, the flow velocities remained unchanged after administration of travoprost (7.9 at T1 versus 7.7 cm/s at T2, p=0.55 and 2.6 versus 2.7 cm/s, p=0.36 for peak systolic and end diastolic velocity respectively). Peak systolic velocity significantly increased after addition of brinzolamide compared to travoprost alone (8.7 cm/s at T3, p=0.003), which was a borderline increase as compared to baseline (p=0.05), whereas end diastolic velocity significantly increased as compared to baseline (2.9 cm/s, p=0.001). Ocular pulse amplitude did not change after administration of travoprost (p=0.19), but decreased markedly after addition of brinzolamide (p=0.005) despite a more important intra-ocular pressure reduction with travoprost than after addition of brinzolamide. Conclusions: Flow velocities improved only in the temporal posterior ciliary artery after topical treatment with travoprost and brinzolamide in glaucoma patients. Ocular pulse amplitude decreased significantly with brinzolamide added to travoprost, but not with travoprost alone.