Diffusion-weighted MRI Lesion Patterns in Large Artery Atherosclerotic Disease with Microembolic Signals

J Korean Neurol Assoc > Volume 26(1); 2008 > Article

Journal of the Korean Neurological Association 2008;26(1): 35-41.

미세 색전 신호를 동반한 큰 동맥질환에서 확산강조영상의 병변 분석

신희영, 김경문

성균관대학교 의과대학 삼성서울병원 신경과학교실

Diffusion-weighted MRI Lesion Patterns in Large Artery Atherosclerotic Disease with Microembolic Signals

Hee-Young Shin

Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea

Abstract

Background: Microembolic signals (MES) are associated with the pathogenic mechanism of ischemic stroke with large-artery atherosclerotic disease. We examined the relationship between MES on a transcranial Doppler ultrasonography (TCD) and lesion patterns on diffusion-weighted MR imaging (DWI) in acute ischemic strokes associated with atherosclerotic diseases of the middle cerebral artery (MCA) and internal carotid artery (ICA).
Methods: A total of 405 consecutive patients were monitored for MES within 48 hours of symptom onset. Patients with MES and DWI lesions in the territory of the MCA or ICA and corresponding MCA/ICA stenosis or occlusion on MR angiography (MRA) were included. MCA velocities and lesion patterns on DWI were compared.
Results: MES were detected in 25 patients (MCA: 13, ICA: 12). The mean number of MES during 30 minutes of monitoring was 14.2±17.3 (range: 1-64, MCA: 13.9±13.6, ICA: 14.5±21.6, p-value=0.098). The mean flow velocity in the ipsilateral MCA in patients with MCA disease was higher than in patients with ICA disease (129.9±74.4 cm/s vs 61.1±28.2 cm/s, p=0.006). The frequency of multiple lesions on DWI was higher inpatients with ICA disease than in those with MCA disease (46.1% vs 100%, p=0.003).
Conclusions: Multiple lesions on DWI were more frequent in ICA disease with MES than in MCA disease. Artery-to-artery embolism may be a more important stroke mechanism in acute ischemic stroke with ICA disease. KeyWords:Middle cerebral artery stenosis, Internal carotid artery stenosis, Diffusion-weighted image, Transcranial Doppler, Microembolic signals