Authors: Wilhelm Küker
Publish Date: 2007/03/08
Volume: 49, Issue: 6, Pages: 471-479
Abstract
Inflammatory stenoses of cerebral blood vessels although rare in general are an important cause of cerebral ischemia in younger patients The diagnosis is often difficult The first step in the diagnostic process is the identification of brain lesions consistent with cerebral vasculitis Brain lesions are frequently found in this patient group especially if modern imaging tools such as diffusion and perfusionweighted imaging are employed Although no specific pattern for this entity exists multiple infarcts of various ages in more than one vascular territory should raise this suspicion The next step in the imaging of patients with suspected vasculitis is the demonstration of the underlying vascular pathology MR angiography is the mainstay of investigating patients for intracranial vascular stenoses However at 15 T it is only diagnostic for stenoses of large brain arteries Hence conventional angiography is still required to investigate stenoses of medium and smallsized brain arteries Recent work suggests that MRI can directly demonstrate mural thickening and contrast enhancement in basal brain arteries rendering biopsy obsolete in this patient group A classification for cerebral vasculitis is proposed according to the size of the affected brain vessels analogous to the pertinent nomenclature of primary systemic vasculitisT2 T2 and DWI images of the whole brain TOFMRA of the large brain arteries and postcontrast T1weighted images of the brain parenchyma Highresolution postcontrast T1weighted images 3 mm or less of areas of abnormality on MRA Vessel wall enhancement should be demonstrated in two planes Axial sequences should be performed using fat suppression and flow compensationSelective injections of both the internal carotid artery and at least one vertebral artery Small field of view 25 cm or less high spatial and temporal resolution at least two frames per second imaging of medium sized brain arteries in at least two planes
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