Diffusion-weighted magnetic resonance imaging in internal carotid artery dissection

Background: Acute multiple brain infarction pattern on diffusion-weighted imaging is associated with arterial or cardiac sources of embolism. Objectives: To review the diffusion-weighted imaging characteristics of patients with strokes secondary to internal carotid artery (ICA) dissection and to gain further insights into the mechanisms of cerebral ischemia. Design: Patients with ICA dissection and ischemic stroke were identified by review of an angiographic database and hospital discharge codes. Patients were included if the diagnosis of ICA dissection was confirmed and diffusion-weighted imaging was obtained within 10 days of symptom onset. Infarct patterns were analyzed according to established templates of vascular territories. Results: Inclusion criteria were met by 14 patients. Internal carotid artery occlusion was present in 10. Acute multiple brain infarction was found in 10 (71%) of the 14 patients. Cortical involvement was found in 8 patients, while the infarct was restricted to the subcortical region in 6. In 9 (64%) of the 14 patients, ischemic lesions were located in 1 of the 3 border zones. Conclusions: Acute multiple brain infarction pattern with border zone involvement is frequently found in ICA dissection-related strokes. This finding may further support an interaction of hemodynamic and embolic mechanisms as a cause of cerebral ischemia in this condition.