Noninvasive MRI Measurement of CBF: Evaluating An Arterial Spin Labelling Sequence with 99mTc-HMPAO CBF Autoradiography in a Rat Stroke Model

Abstract

Arterial spin labelling (ASL) is increasingly available for noninvasive cerebral blood flow (CBF) measurement in stroke research. Here, a pseudo-continuous ASL technique (pCASL) was evaluated against 99mTc-D, L-hexamethylpropyleneamine oxime (99mTc-HMPAO) autoradiography in a rat stroke model. The 99mTc-HMPAO was injected (intravenously, 225 MBq) during pCASL acquisition. The pCASL and 99mTc-HMPAO autoradiography CBF measures, relative to the contralateral hemisphere, were in good agreement across the spectrum of flow values in normal and ischemic tissues. The pCASL-derived quantitative regional CBF values (contralateral: 157 to 177 mL/100 g per minute; ipsilateral: 9 to 104 mL/100 g per minute) were consistent with the literature values. The data show the potential utility of pCASL for CBF assessment in a rat stroke model.