Background and purpose: Whether hemodynamic and/or embolic transcranial Doppler (TCD) features of internal carotid artery (ICA) stenosis contribute to the classification of stroke patterns on MRI.
Patients and methods: Consecutive patients presenting symptomatic ≥50% ICA stenosis were included. Microembolic signals (MES) detection and measurement of cerebral vasoreactivity (VR) were performed by TCD. Only acute MRI lesions, territorial (TT) and/or borderzone (BZ) were considered.
Results: A total of 72 ICA stenoses, 27 (38%) moderate (50-69%), and 45 (62%) high grade (70-99%) were included. MRI lesions showed 32 (44%) pure TT, 20 (28%) pure BZ, and 20 (28%) mixed TT and BZ. Impaired VR was found more frequently among patients with higher degrees of stenoses (P < .001) whereas MES were similarly encountered in both groups (P = NS). Impaired VR was more common in the BZ (10/20, 50%) than in the TT group (9/32, 28%, P < .1) while MES were present in 47% (15/32) of patients with TT and in 30% (6/20, P < .1) of those with BZ lesions, in particular in cortical BZ infarcts (P < .02).
Conclusion: Our findings suggest that TCD characteristics of the ICA stenosis contribute to better define stroke patterns on MRI in about one-third of the patients presenting with pure TT or BZ lesions.
Keywords: Territorial stroke; cerebral vasoreactivity; hemodynamic stroke; microembolic signals; transcranial Doppler.
Copyright © 2014 by the American Society of Neuroimaging.