Evaluation of posterior cerebral artery flow velocity by transcranial color-coded real-time sonography

Using transcranial color-coded real-time sonography (TCCS), we measured peak-systolic flow velocities (PSVs) in segment P2 of 102 posterior cerebral arteries (PCAs) in 61 patients, with angiography. We divided 102 PCAs into four groups: control group (n = 70) with no significant stenotic lesions; PCS group (n = 7) with stenosis >/= 50% of P2 segment; Col (+) group (n = 13) and Col (-) group (n = 12) had occlusive lesions in the carotid system with or without collateral flow from PCA to the middle cerebral artery through the leptomeningeal anastomosis. In the PCS group, PSV (255.7 +/- 67.2 cm/s) was higher than in the other three groups (p < 0.0001). PSV was higher in the Col (+) group (127.6 +/- 31.2) than in the Col (-) (86.6 +/- 20.1) and control (83.8 +/- 24.8) groups (p < 0.001). The measurement of PSV in the P2 segment of PCA using TCCS may help to identify a significant stenosis in PCA.