Prognostication of recovery following stroke using the comparison of CT and technetium-99m HM-PAO SPECT.

This study investigated the possibility that a relationship between the anatomic defects observed on computed tomography (CT) and the functional defects observed on single photon emission computed tomography (SPECT) might be used as an outcome measure to predict clinical recovery from the neurologic deficits induced by stroke. Twenty-seven patients with stroke location limited primarily to cerebral cortex were included in the study: each patient underwent a cranial CT scan, 99mTc hexamethylpropyleneamineoxime SPECT cerebral perfusion scan, and an initial and 1-yr follow-up neurologic examination. A strongly positive correlation between the ratio of the SPECT to CT volume defect sizes (SPECT divided by CT) and recovery following stroke was found, such that the greater the SPECT to CT ratio, the better the subsequent recovery of neurological deficits. Discriminant function analysis revealed that the best predictor of clinical outcome following stroke was the log-transformation of SPECT divided by CT. The results suggest that the relationship between the perfusion defects and tissue loss measured by SPECT and CT imaging may have prognostic utility following stroke limited primarily to cerebral cortex.