Search results for "Circle of Willis"

2020

Background: Computed tomography angiography (CTA) is frequently used with computed tomography perfusion imaging (CTP) to evaluate whether endovascular vasospasm treatment is indicated for subarachnoid hemorrhage patients with delayed cerebral ischemia. However, objective parameters for CTA evaluation are lacking. In this study, we used an automated, investigator-independent, digital method to detect vasospasm, and we evaluated whether the method could predict the need for subsequent endovascular vasospasm treatment. Methods: We retrospectively reviewed the charts and analyzed imaging data for 40 consecutive patients with subarachnoid hemorrhages. The cerebrovascular trees were digitally rec…

Extracranial internal carotid artery occlusion: the role of common carotid artery volume flow.

2002

BACKGROUND AND PURPOSE Quantitative measurement of blood flow volume in the common carotid artery (CCA) is now possible using the color velocity imaging quantification (CVI-Q) ultrasound technique. The aim of this study was to evaluate the cerebral hemodynamic effects of unilateral internal carotid artery (ICA) occlusion on CCA blood flow volumes (FVs) using CVI-Q. METHODS Records of ultrasound studies in our neurosonology laboratory were retrospectively reviewed to identify patients with unilateral ICA occlusions who at a minimum received both a routine color duplex carotid ultrasound examination and quantitative measurement of FV in the CCA, bilaterally, using the CVI-Q method. A total of…

Intracranial pathology of the visual pathway.

2004

Intracranial pathologies involving the visual pathway are manifold. Aligning to anatomy, the most frequent and/or most important extrinsic and intrinsic intracranial lesions are presented. Clinical symptoms and imaging characteristics of lesions of the sellar region are demonstrated in different imaging modalities. The extrinsic lesions mainly consist of pituitary adenomas, meningeomas, craniopharyngeomas and chordomas. In (asymptomatic and symptomatic) aneurysms, different neurological symptoms depend on the location of aneurysms of the circle of Willis. Intrinsic tumors as astrocytoma of any grade, ependymoma and primary CNS-lymphoma require the main pathology in the course of the visual …

Atypical posterior circulation strokes: a case-based review of rare anatomical variations involved

2021

The circle of Willis is a very important vascular mechanism of protecting against cerebral ischemia, especially when circulation within the main arteries irrigating the brain is somehow impeded. As result of congenital malformation arising early in embryonic development, the fetal-type posterior circle of Willis remains as such during the rest of one's life. Consequently, the posterior cerebral artery (PCA) becomes a branch of the internal carotid artery (ICA), rather than of the basilar artery (BA). Furthermore, the rest of collateral circulation, between the anterior and the posterior regions of the brain, is also negatively affected (e.g., leptomeningeal vessels). The anatomical variant …

Applied Anatomy of the Cerebral Arteries

1991

Four arteries supply the brain with blood: the two carotid and the two vertebral arteries. Although these four vessels are ultimately interlinked via a basal arterial network, the circle of Willis, and anastomoses at the brain surface, Heubner’s anastomoses, it is useful to distinguish anterior (carotid anterior and middle cerebral) and posterior (vertebrobasilar posterior cerebral) vascular territories (Gillian 1957, 1968; Lazorthes 1961; Kaplan and Ford 1966; Ganshirt 1972; Seeger 1978; Dorndorf 1983; Duus 1983).

Angio-RM a confronto con angiografia digitale nella diagnosi degli aneurismi cerebrali.

2007

Poster congresso nazionale AINR. Bergamo, 20-23 Giugno 2007