Effect of bimatoprost on ocular circulation in patients with open-angle glaucoma or ocular hypertension

Purpose: To study the effect of bimatoprost 0.03% (Lumigan) on ocular hemodynamics in patients with open-angle glaucoma or ocular hypertension. Methods: One randomly selected eye of each of 26 patients with open-angle glaucoma or ocular hypertension was enrolled. Each patient received a drop of bimatoprost 0.03% once daily for I month. The effect of bimatoprost on ocular circulation was assessed by color Doppler imaging (CDI), which measured peak systolic, end-diastolic blood flow velocities and resistance indices in the ophthalmic, posterior ciliary and central retinal arteries. Retrobulbar hemodynamics by CDI, intraocular pressure by Goldmann applanation tonometer, blood pressure by cuff, and heart rate by palpation were measured at baseline and at 1 month after bimatoprost treatment. Results: Blood flow velocities and resistance indices in all retrobulbar vessels showed no statistically significant differences between baseline and bimatoprost condition (P>0.05). Bimatoprost lowered intraocular pressure significantly (P<0.001), with a mean change of 6.5 mmHg (27%) after 1 month of treatment. The systolic (P=0.38) and diastolic (P=0.74) blood pressures and pulse rate (P=0.94) did not show statistically significant differences during the study period. Conclusions: The results of this study suggest that topical bimatoprost 0.03% significantly reduces intraocular pressure in patients with open-angle glaucoma or ocular hypertension. However, it does not have any effect on retrobulbar hemodynamics in open-angle glaucoma and ocular hypertension.