Perfusion MRI before and after acetazolamide administration for assessment of cerebrovascular reserve capacity in patients with symptomatic internal carotid artery (ICA) occlusion: comparison with 99mTc-ECD SPECT.

Introduction Impaired cerebral vascular reserve (CVR) in patients with symptomatic internal carotid artery (ICA) occlusion is regarded as a possible indication for performing extra-/intracranial (EC/IC) bypass surgery. As perfusion MR imaging (MRI) can demonstrate cerebral haemodynamics at capillary level, our hypothesis was that perfusion MRI could be used in these patients for the evaluation of CVR following acetazolamide challenge in a similar way to single photon emission CT (SPECT) and might provide additional information.