Abstract 2971: Atheromatous Plaques of the Middle Cerebral Artery in the Lateral Lenticulostriate Artery Territory Infarction

Abstract

OBJECTIVES: We evaluated the utility of black-blood double inversion recovery magnetic resonance imaging (BBDIR-MRI) for depiction of the intracranial branch atheromatous disease caused by occlusion at the vessel orifices of lager-caliber penetrating arteries. METHODS: BBDIR-MRI was performed on 15 consecutive patients with acute cerebral infarcts in the territories of lateral lenticulostriate arteries, which were classified into small artery occlusion by TOAST criteria. Abnormal wall thickening of the horizontal part (M1) of the middle cerebral artery was considered as the atheromatous plaque causing the occlusion of the vessel orifices. The clinical characteristics including the prevalence of various vascular risk factors, the final size of infarcts and the rate of disease progression were compared between two groups with and without the atheromatous plaque. RESULTS: By BBDIR-MRI, the atheromatous plaques were detected in 8 patiennts (53%), while Time of flight (TOF)-MRA revealed the irregular stenosis in one patient. All of them had the eccentric wall thickening with iso-signal intensity on T1- and T2-weighted images of BBDIR-MRI. The large infarcts exceeding 1.5 cm in diameter tended to be more often in patients with the atheromatous plaque (100%) than those without it (57%). However, there were no significant differences of clinical characteristics between the two groups with and without the atheromatous plaque. CONCLUSIONS: BBDIR-MRI could reveal the atheromatous plaque at M1 portion of the middle cerebral artery more easily than TOF-MRA. It might be useful to distinguish the intracranial branch atheromatous diseases from the other types of infarcts in the territories of lateral lenticulostriate arteries.