Applying Transcranial Doppler (TCD) we have measured the mean blood flow velocities in the arteries of the circle of Willis, and during the 2nd measurement, the results were a decreased velocity in the right MCA (Middle Cereberal Artery) in 46.7% of the patients. During the 1st measurement we registered a decreased blood flow velocity in the left MCA in 56.7% of the patients. During the 2nd measurement, a decreased blood flow velocity was noticed in the right MCA in 48.3% of the patients, and in the left MCA among 55% of patients. These values confirm that the cases of severe stenotic changes in extra-cranial blood vessel, or an increased circulation resistance due to the generalized atherosclerosis in the cases of synergic impact on multiple pathological changes in the brain blood vessels. Barkat and colleagues, among numerous other authors, showed by TCD that atherosclerotic changes of extra-cranial part of ICA (Internal Carotid Artery) (occlusion or stenosis greater than 70%) leads to reduction of mean blood flow velocities in the same side of MCA that was registered in our study as well. Increased velocities in the right MCA during the 1st measurement was noted among 15% of patients, while, during the 2nd test, a reduction was noted in the right MCA in 11% of the cases. Normal values in the right MCA during the 1st measurement were registered in 38.3% of the patients, while during the 2nd measurement it was normal in 40% of the cases.
Key words: stroke, diagnosis, transcranial Doppler