Retinal peripapillary blood flow before and after topical brinzolamide

PURPOSE: To study the effect of topical brinzolamide on retinal capillary blood flow by the Heidelberg Retina Flowmeter (HRF) in patients with glaucoma. METHODS: Twenty patients with glaucoma were consecutively recruited. One eye for each patient was randomly selected. Patients were classified as glaucomatous if they had an abnormal visual field and/or an abnormal optic nerve head with an intraocular pressure (IOP) greater than 21 mm Hg without any treatment. After an eye examination, baseline retinal blood flow measurements were made with confocal scanning laser Doppler flowmetry. Blood flow and IOP measurements were then repeated after 1 month of treatment. Blood flow measurements were analyzed by using an automatic full-field perfusion image analysis (AFFPIA) program. The blood flow was calculated in the superior and inferior part of the optic disk. In each area, the blood flow was calculated as temporal area, the nasal area and the rim area as for software AFFPIA. RESULTS: The mean age of the patients was 56 +/- 7 (mean +/- standard deviation) years. The mean IOP before treatment was 23.7 +/- 1.5 mm Hg while the mean IOP after 4 weeks of treatment was 19.1 +/- 2.2 mm Hg. This difference was statistically significant (p < 0.01). Significant (p < 0.05) increases in retinal blood flow were found for the temporal and nasal areas between baseline and 1 month after the treatment. No difference was found between superior and inferior sectors. CONCLUSION: Topical brinzolamide reduced the IOP significantly and apparently improved retinal blood flow as measured by the HRF.