J Korean Neurol Assoc.  1996 Mar;14(1):46-52.

Clinical Usefulness of Magnetic Resonance Angiography in Patients with Cerebellar and/or Brainstem Infarction

• Kim HC
• Song HK
• Lee BC

Abstract

BACKGROUND & OBJECTIVE: Magnetic resonance angiography is helpful noninvasive evaluation of intracranial arteries and, in some patients, may spare invasive angiography which has potentially serious complication. However, it's diagnostic value in vertebrobasilar artery disease has not yet been evaluated.
METHODS
MRA and axial brain MRI of 47 patients with acute cerebellar and/or brainstem ischemia, 26 patients with middle cerebral artery territory infarction, and 40 age matched normal controls were reviewed. Patients wit potential risks of cardiac embolization were excluded. MR Angiography was performed by three dimensional time-of-flight gradient-echo technique. Th diagnosis of vessel stenosis was made only when the lumen diameter was reduced by less than 50% on 3-D images to avoid overestimation of MR angiography.
RESULTS
Forty-seven patients had cerebellar and/or brainstem infarction: with signal hyperintensities in T2-weighted MRI sequences. Pons was the most common infarcted site(28/47), followed by medulla (17/47), and cerebellum (11/47). The sensitivity of MR angiography in detecting vascular occlusive lesions of vertebrobasilar artery was 57.5% (28/47) in cerebellar and/or brainstem infarction patients, while 7 of 26 (26.9%) in middle cerebral artery territory infarction, and 2 of 40 (5%) in age matched control subjects showed occlusion or stenosis. MR angiography detected vascular occlusive lesions more frequently on vertebral arteries (25/47, 53.2%) than basilar artery (13/47, 27.7%). And occlusive or stenotic lesions of vertebral arteries were ipsilateral to ischemic lesion sites in 12 of 17 patients(70.6%), There was no difference between deep small lacunar stroke and perforator occlusion in pons. Absence of flow void on axial T2W imaging was seen only in 9 of 47 patients (19.1%).
CONCLUSIONS
The results in this present study suggest that MR angiography is moderately sensitive diagnostic tool in vertebrobasilar occlusive disease although it has limitation in detection of smaller branches occlusion. Except vertebral arteries occlusion, absence of flow void in axial MR imaging is not a reliable findings.

MeSH Terms

Angiography
Arteries
Basilar Artery
Brain
Brain Stem Infarctions*
Brain Stem*
Cerebellum
Constriction, Pathologic
Diagnosis
Humans
Imaging, Three-Dimensional
Infarction
Ischemia
Magnetic Resonance Angiography*
Magnetic Resonance Imaging
Middle Cerebral Artery
Pons
Stroke, Lacunar
Vertebral Artery