UNLABELLED: Technetium-99m-HMPAO can be used to evaluate abnormal brain perfusion in the hyperacute stage of stroke. METHODS: We investigated cerebral blood flow using 99mTc-HMPAO SPECT in 31 patients within 6 hr after the onset of cerebral infarction and analyzed the relationship between abnormal perfusion and morphological changes on follow-up CT scans. Patients were classified into an infarct group and a noninfarct group, and the lesions on SPECT images were divided into infarct and peri-infarct regions. RESULTS: Among a total of 30 infarct regions, three lesions studied at 1.5, 2.5 and 5 hr after the ictus showed local hyperperfusion suggestive of early postischemic hyperemia, while the other 27 lesions demonstrated local hypoperfusion. All of the peri-infarct regions showed moderate hypoperfusion. The noninfarct group consisted of five patients, four of whom showed no perfusion abnormalities. The lesion-to-contralateral radioactivity ratios for the infarct and peri-infarct regions were respectively 0.48 +/- 0.14 and 0.75 +/- 0.10 in the patients with hypoperfusion, while the right-to-left ratio in the noninfarct group was 0.97 +/- 0.10. CONCLUSION: This SPECT study of cerebral blood flow demonstrates that local hyperperfusion occurs in some infarcts even within 6 hr of onset and that infarcted and morphological viable brain can be distinguished by a lesion-to-contralateral radioactivity ratio of 0.6 within this time range.
UNLABELLED: Technetium-99m-HMPAO can be used to evaluate abnormal brain perfusion in the hyperacute stage of stroke. METHODS: We investigated cerebral blood flow using 99mTc-HMPAO SPECT in 31 patients within 6 hr after the onset of cerebral infarction and analyzed the relationship between abnormal perfusion and morphological changes on follow-up CT scans. Patients were classified into an infarct group and a noninfarct group, and the lesions on SPECT images were divided into infarct and peri-infarct regions. RESULTS: Among a total of 30 infarct regions, three lesions studied at 1.5, 2.5 and 5 hr after the ictus showed local hyperperfusion suggestive of early postischemic hyperemia, while the other 27 lesions demonstrated local hypoperfusion. All of the peri-infarct regions showed moderate hypoperfusion. The noninfarct group consisted of five patients, four of whom showed no perfusion abnormalities. The lesion-to-contralateral radioactivity ratios for the infarct and peri-infarct regions were respectively 0.48 +/- 0.14 and 0.75 +/- 0.10 in the patients with hypoperfusion, while the right-to-left ratio in the noninfarct group was 0.97 +/- 0.10. CONCLUSION: This SPECT study of cerebral blood flow demonstrates that local hyperperfusion occurs in some infarcts even within 6 hr of onset and that infarcted and morphological viable brain can be distinguished by a lesion-to-contralateral radioactivity ratio of 0.6 within this time range.
Authors: K Nael; E Tadayon; D Wheelwright; A Metry; J T Fifi; S Tuhrim; R A De Leacy; A H Doshi; H L Chang; J Mocco Journal: AJNR Am J Neuroradiol Date: 2019-08-14 Impact factor: 3.825
Authors: R A Dierckx; A Dobbeleir; B A Pickut; L Timmermans; I Dierckx; A Vervaet; J Vandevivere; W Deberdt; P P De Deyn Journal: Eur J Nucl Med Date: 1995-05
Authors: Pamela W Schaefer; Yelda Ozsunar; Julian He; Leena M Hamberg; George J Hunter; A Gregory Sorensen; Walter J Koroshetz; R Gilberto Gonzalez Journal: AJNR Am J Neuroradiol Date: 2003-03 Impact factor: 3.825