Imaging of spontaneous neuromagnetic activity in a patient with internal carotid artery stenosis

Abstract

A 76-year-old man suffered a ischemic attack resulting in left hemiparesis, and brain magnetic resonance imaging (MRI) confirmed a small infarct in the watershed area of the right parieto-occipital region [Figure 1]a. Cerebral angiography confirmed approximately 80% stenosis at the origin of the right internal carotid artery [Figure 1]b. Positron emission tomography by the 15 O gas inhalation (steady-state) method ( 15 O gas PET) confirmed a decrease in cerebral blood flow (CBF) in the region of the right middle cerebral artery (right 36.2ml/100g /min; left 40.7ml/100g /min) [Figure 2]a and increased oxygen extraction fraction (OEF) (right 45.2%; left 37.7%) [Figure 2]b. The patient was thus diagnosed to have reduced CBF and metabolism reserve (misery perfusion) in the right middle cerebral artery region.