FIG. 3.

Multimodality imaging in acute ischemic stroke. Top panel demonstrates obscuration of the caudate and putamen (arrows) in a patient with right hemiparesis and aphasia on noncontrast CT (a). CTA source image shows decreased vascular signal in the territory of the lenticulostriates (arrows) in the left hemisphere with increased vascular signal in the overlying cortex (b). DWI shows injury pattern (arrow) in the region that is abnormal on the CTA source images (c). Second panel demonstrates single slab CT perfusion study with low CBV (arrow) in the region abnormal on the DWI and CTA source image (d). MTT (e) and CBF (f) are abnormal throughout the left hemisphere congruous with the clinical deficit (arrows). Third panel demonstrates MR perfusion with CBV (g), MTT (h) and CBF (i) with findings identical to those demonstrated with CT perfusion (arrows). Bottom panel demonstrates the vascular lesions. Panel j is a CTA of the extracranial carotid showing beak like tapering characteristic of carotid dissection (arrow). Panel k is a digital subtraction angiogram of the left carotid. Panel l is a MR angiogram demonstrating the same arterial obstruction in the left internal carotid artery (arrow). Panel m is a thick CT slice taken after a bolus of CT dye demonstrating the left middle cerebral artery clot on the coronal image (arrow). Note that there is no computer reconstruction, only a thick CT slice, which is available within 2–5 min of imaging. Panel n shows the final infarct that evolved to include the entire region that was abnormal on MR and CT bolus tracking perfusion scans (arrows).