Prediction of cerebral vasospasm using early stage transcranial Doppler.
Transcranial Doppler (TCD) is widely used to monitor vasospasm after subarachnoid hemorrhage (SAH), but its ability to predict the future occurrence of the symptomatic vasospasm (SVS) remains controversial. We investigated the utility of TCD for predicting the future occurrence of SVS after SAH in 45 patients with aneurysmal SAH. TCD was performed on days 1, 3, 5, 7, 10, and 14 after SAH. The mean flow velocity (MFV) of the horizontal portion of the middle cerebral artery (M1) was recorded. SVS occurred in 24.4% of patients (n = 11). MFV of M1 increased progressively in patients with SVS, but did not increase in patients without SVS. The mean MFV values were significantly higher in patients with SVS than in patients without SVS (p = 0.031). The mean MFV value on day 3 was already significantly higher in patients with SVS than in patients without SVS (88.5 cm/sec versus 62.7 cm/sec, respectively) (p = 0.018). The receiver operating characteristic curve of MFV on day 3 showed the threshold of 72.5 cm/sec for predictive value of SVS in the future (sensitivity 71.4%, specificity 68.1%, and accuracy 82.3%). Increased MFV of M1 during the early stage of SAH may predict the future occurrence of SVS. The threshold value of 72.5 cm/sec MFV of M1 on SAH day 3 was one of the best predictor of future SVS. To prevent delayed cerebral ischemia, aggressive treatment for vasospasm is needed for patients with increased MFV in the early stages of SAH.