Comparison of MRI perfusion imaging and single photon emission computed tomography in chronic stroke

There have been few direct comparisons between MR perfusion-weighted imagin g (PWI) and established perfusion imaging techniques, and none in chronic s troke. We therefore studied 17 chronic hemispheric infarction patients (mea n, 90 days) and compared hypoperfusion volumes determined from PWI maps of relative cerebral blood flow (rCBF) and volume (rCBV), and mean transit tim e (rMTT) with those measured with Tc-99-HMPAO single photon emission comput ed tomography (SPECT). Comparisons were also made between infarct size (T-2 - WI) and clinical scales. Correlations were found between lesion location and volume in all three PWI hemodynamic parameter maps with clinical state and lesions on SPECT and T-2-WI. In 3 patients, rCBF and rCBV lesions exten ded well beyond the borders of moderate-sized infarctions, We conclude that in chronic stroke, PWI can delineate regions of abnormal perfusion that re flect the degree of functional impairment and structural damage. The findin g of peri-infarct hypoperfusion suggests that PWI may have the potential to provide a rapid and noninvasive template against which interventional stra tegies aimed at promoting functional recovery may be investigated. Copyrigh t (C) 2001 S. Karger AG, Basel.