OCULAR AND CEREBRAL BLOOD-FLOW MEASUREMENTS IN HEALTHY-SUBJECTS - A COMPARISON OF BLOOD-FLOW VELOCITY AND DYNAMIC TONOMETRY MEASUREMENTS BEFORE AND AFTER ACETAZOLAMIDE

The ocular and cerebral blood flow was studied in 15 healthy subjects using transcranial Doppler ultrasonography (2 MHz). The blood now velo city in the precerebral carotid arteries, in the ophthalmic artery and in the middle cerebral artery was measured under baseline conditions and after i.v. administration of Ig acetazolamide. To measure the intr aocular pressure and the corneal indentation pulse amplitude, a dynami c tonometer was used. Pulsatile ocular blood volume was calculated fro m these values. After one single dose of acetazolamide a significant d ecrease in ophthalmic artery now velocity, and a significant increase both in internal carotid and in middle cerebral artery velocity was fo und. A significant decrease in intraocular pressure and in pulsatile o cular volume after acetazolamide was also demonstrated. These findings suggest that the acute effect of acetazolamide may be associated with a reduced ocular blood flow explaining some of the reduction in IOP.