Transcranial color-coded sonography in normal Chinese adults and its clinical applications.

We have performed transcranial color-coded sonography to 150 normal adults. Through the temporal, orbital and foraminal windows, by using a 2 MHz pulsed-wave transducer, we were able to directly insonate the brain parenchyma, and to obtain color-coded Doppler vascular imagings and flow velocities of the intracranial basal cerebral arteries. There was no significant difference of blood flow velocities and resistance index between the right and left hemispheres. The mean velocities was highest in the middle cerebral artery and lowest in the ophthalmic artery while which had the highest resistance index. Female had higher mean velocity in basilar artery. The mean velocity, peak systolic velocity, as well as end diastolic velocity decreased significantly with age in middle cerebral artery, anterior cerebral artery and basilar artery. Four illustrative cases with abnormal findings were presented to compare with normal control. Some pitfalls in ultrasonography were also described.