[A study of cerebral vasospasm after subarachnoid hemorrhage with transcranial Doppler].

Transcranial Doppler (TCD) was performed in 64 patients with subarachnoid hemorrhage (SAH) to detect the blood velocity in middle cerebral artery (MCA). Based on Poiseuille's principle, the increase of blood velocity was used as an indicator of cerebral vasospasm (CVS). It was found that 61.67% of the patients with SAH developed CVS, especially in the second week after SAH. The incidence of CVS in patients below 50 years old was higher than that in patients above 51 years old. The results showed that TCD is valuable in evaluation of CVS after SAH.