The correlation between motor impairment and cerebral blood flow in Sturge-Weber syndrome

Recent studies of regional cerebral blood flow (rCBF) and cerebral metabolism in patients with Sturge-Weber syndrome (SWS) have demonstrated a regional decrease of CBF and metabolism in the affected hemisphere, which may reflect the neurological status of the patients. Therefore, in the present study, we use stable xenon computed tomography (xenon-CT) and/or (99m)technetium hexamethylprophylene amine oxime ((99mTc)HMPAO) single photon emission computed tomography (SPECT) to determine whether the degree of cerebral hemodynamic disturbance correlates with the severity of motor impairment in 5 children with Sturge-Weber syndrome. We found that 5 patients had great variation in clinical progression and outcome, but MR imaging investigations all revealed extensive but stable abnormalities. rCBF, assessed by stable xenon-CT and/or (99mTc)HMPAO-SPECT, showed perfusion defect in all subjects. However, the xenon-CT disclosed reduction of rCBF and cerebrovascular reactivity in patients with severe motor paralysis. The total CBF and rCBF detected by xenon-CT were improved after clinical status was stabilized. We conclude that the motor function impairment in patients with SWS appeared to better correlate with the degree of rCBF impairment than with the abnormalities in conventional neuroimaging. Therefore, the quantitative CBF study is one of the diagnostic modality of choice in evaluating the neurological status in patients with SWS.