Differences in the longterm effect of timolol and betaxolol on the pulsatile ocular blood flow

In the past several years the effect of longterm glaucoma therapy on ocular hemodynamics has taken on increased interest. This interest has been sparked by studies demonstrating differential effects of various beta-blockers on visual function, and the possible contributory role of ocular blood flow. In the present study, the pulsatile ocular blood flow (POBF), as derived by the Langham OBF system, was measured prior to treatment and then tracked throughout a one-year period of beta-blocker therapy (betaxolol 0.5% or timolol 0.5%) in 25 glaucoma patients. Results of the two treatments were compared, and indicated that, whereas both betaxolol- and timolol-treated patients had similar significant reductions in the IOP, the effect of the two treatments on the POBF differed. In timolol-treated patients, the POBF decreased significantly over the 12-month observation period, whereas in betaxolol-treated patients it remained stable.