M Mull1, M Schwarz, A Thron. 1. Department of Neuroradiology, University Hospital of the Technical University (RWTH), Aachen, Germany.
Abstract
BACKGROUND AND PURPOSE: Among the pathogenetic causes of subcortical hemispheric infarcts are small-vessel disease, thromboembolic occlusions of small arteries, and hemodynamic compromise in low-flow conditions. A topographic classification of these infarcts based on CT and MRI can be misleading. METHODS: We evaluated 30 consecutive patients with presumed supratentorial low-flow infarcts. CT was available in all cases, with additional MRI in 14 patients. In all cases the occlusion pattern of the extracranial and intracranial arterial system was studied in detail with angiography. RESULTS: The dominant lesion patterns seen on CT and MRI were multilocal chainlike lesions in 19 and confluent striated lesions in 8 cases located in the supraventricular and paraventricular deep white matter. In 8 patients subcortical lesions extended into the adjacent cortex. Angiography revealed that extracranial occlusive disease (n = 24) or stenosis of the middle cerebral artery (n = 6) was always accompanied by impairment of the circle of Willis, in either the anterior part (n = 25) and/or the posterior part (n = 16). Moreover, leptomeningeal pathways indicative of vascular hemispheric compromise were identified in 26 cases. In total, 29 of 30 patients displayed a noncompetent circle of Willis. CONCLUSIONS: Low-flow infarcts show typical but not pathognomonic lesion patterns on CT and MRI. Definite diagnosis requires knowledge of the complex vascular compromise of the extracranial and/or intracranial arterial system. A noncompetent circle of Willis should be regarded as the additional predisposing condition in hemispheric low-flow infarcts.
BACKGROUND AND PURPOSE: Among the pathogenetic causes of subcortical hemispheric infarcts are small-vessel disease, thromboembolic occlusions of small arteries, and hemodynamic compromise in low-flow conditions. A topographic classification of these infarcts based on CT and MRI can be misleading. METHODS: We evaluated 30 consecutive patients with presumed supratentorial low-flow infarcts. CT was available in all cases, with additional MRI in 14 patients. In all cases the occlusion pattern of the extracranial and intracranial arterial system was studied in detail with angiography. RESULTS: The dominant lesion patterns seen on CT and MRI were multilocal chainlike lesions in 19 and confluent striated lesions in 8 cases located in the supraventricular and paraventricular deep white matter. In 8 patients subcortical lesions extended into the adjacent cortex. Angiography revealed that extracranial occlusive disease (n = 24) or stenosis of the middle cerebral artery (n = 6) was always accompanied by impairment of the circle of Willis, in either the anterior part (n = 25) and/or the posterior part (n = 16). Moreover, leptomeningeal pathways indicative of vascular hemispheric compromise were identified in 26 cases. In total, 29 of 30 patients displayed a noncompetent circle of Willis. CONCLUSIONS: Low-flow infarcts show typical but not pathognomonic lesion patterns on CT and MRI. Definite diagnosis requires knowledge of the complex vascular compromise of the extracranial and/or intracranial arterial system. A noncompetent circle of Willis should be regarded as the additional predisposing condition in hemispheric low-flow infarcts.
Authors: Arjan W J Hoksbergen; Charles B L Majoie; Frans-Jan H Hulsmans; Dink A Legemate Journal: AJNR Am J Neuroradiol Date: 2003-03 Impact factor: 3.825
Authors: Benjamin S Geisler; Joachim Röther; Thomas Kucinski; Hermann Zeumer; Bernd Eckert Journal: AJNR Am J Neuroradiol Date: 2005-03 Impact factor: 3.825