Prediction of Stroke Rehabilitation Outcome with Xenon-enhanced Computed Tomography Cerebral Blood Flow Study

Abstract

Cerebral blood flow (CBF) of stroke patients in the chronic stage is supposed to reflect brain functions. We examined the relation between rehabilitation outcome and CBF values. The study group comprised 101 consecutive patients (mean age, 69±12 years) including 61 patients with cerebral infarction, 32 patients with cerebral hemorrhage, and 8 patients with subarachnoid hemorrhage. Xenon-enhanced computed tomography was performed on 39 days on average after stroke onset. Regions of interest were in the cerebral cortices, putamen and thalamus, and CBF values were statistically compared with the functional independence measure (FIM). Furthermore, we performed a multivariate analysis for predictive factors. 1. The right mean CBF (mCBF) tended to be more closely correlated with the FIM total scores at discharge (r=0.495, P<.001) than the left mCBF (r=0.351, P<.001), in case of significance level 0.1 and statistical power 0.65. 2. The FIM total and motor scores at discharge showed the highest correlations to regional CBF (rCBF) in the right frontal cortex, and the FIM cognitive scores at discharge showed the highest correlation to rCBF in the left frontal cortex. 3. Right cerebral infarct subgroup (n=30) showed significant correlations between FIM total scores at discharge and mCBF values of the right (r=0.582, P<.001) and the left (r=0.563, P<.005) brain, respectively. 4. Rehabilitation outcome evaluated with the FIM total scores could be led by the formulae with the factors of age, gender, NIHSS, right/left hemispheric lesions and the right mCBF values (r=0.837, P<.001). The CBF of the right brain proved to be more influencing to rehabilitation results.