Middle cerebral artery plaque and prediction of the infarction pattern.

Background: Intracranial atherosclerosis is associated with recurrent ischemic stroke. High-resolution magnetic resonance imaging can provide information about atheroma in vivo including plaque volume, composition,and activity.

Objective: To evaluate atherosclerosis activity of the middle cerebral artery (MCA) by high-resolution magnetic resonance imaging and determine its relationship with infarction patterns.

Design: Patients with MCA territory infarction or transient ischemic attack were enrolled and 3-T high resolution magnetic resonance imaging was performed in the relevant MCA. We analyzed the status of the intracranial atheroma and infarction pattern in the corresponding vascular territory. Intracranial atheroma was defined as vulnerable symptomatic plaque when it was accompanied by intraplaque heterogeneous signal intensity and plaque enhancement, and as a stable symptomatic plaque otherwise. Cerebral infarction pattern was defined as artery-to-artery embolic infarction when multiple lesions were present within the MCA territory.

Setting: A tertiary referral center.

Patients: A total of 34 patients were enrolled in the study;14 patients had stable symptomatic plaque, 12 had vulnerable symptomatic plaque, and 8 had no plaque (normal group).

Main outcome measures: Intracranial atheroma stability and infarction pattern.

Results: High-resolution magnetic resonance images were acquired from 34 patients, which revealed the presence of stable symptomatic plaque in 14 patients and vulnerable symptomatic plaque in 12 patients. The patients with vulnerable symptomatic plaque more commonly demonstrated an artery-to-artery embolic infarction pattern than the patients with stable symptomatic plaque (P=.02).

Conclusions: Vulnerable symptomatic plaque as determined by a high-resolution magnetic resonance imaging technique is associated with artery-to-artery embolic infarction.This novel imaging technique can provide information about intracranial atherosclerosis in vivo, which can predict the infarction pattern.