AJNR. American journal of neuroradiology
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AJNR Am J Neuroradiol · Nov 2005
Comparative StudySurface appearance of the vertebrobasilar artery revealed on basiparallel anatomic scanning (BPAS)-MR imaging: its role for brain MR examination.
Basiparallel anatomic scanning (BPAS)-MR imaging is a simple MR imaging technique that we designed for visualization of the surface appearance of the vertebrobasilar artery within the cistern. It can clearly show the outer contour of occluded arteries or thrombosed aneurysms. By comparing BPAS-MR imaging with 3D time-of-flight (TOF) MR angiography (MRA), we can precisely evaluate the vertebrobasilar artery condition. The purpose of this study is to determine the value of BPAS-MR imaging for brain MR examination. ⋯ The combination of the BPAS-MR imaging and the 3D TOF MRA was necessary for accurate diagnosis in 16.1% of our ordinary patients. We should evaluate not only MRA but also the vascular outer contour revealed on BPAS-MR imaging, though its application is limited to the vertebrobasilar system and the screening use.
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AJNR Am J Neuroradiol · Nov 2005
Characterization of cerebral aneurysms for assessing risk of rupture by using patient-specific computational hemodynamics models.
Hemodynamic factors are thought to play an important role in the initiation, growth, and rupture of cerebral aneurysms. This report describes a pilot clinical study of the association between intra-aneurysmal hemodynamic characteristics from computational fluid dynamic models and the rupture of cerebral aneurysms. ⋯ Image-based patient-specific numeric models can be constructed in an efficient manner that allows clinical studies of intra-aneurysmal hemodynamics. A simple flow characterization system was proposed, and interesting trends in the association between hemodynamic features and aneurysmal rupture were found. Simple stable patterns, large impingement regions, and jet sizes were more commonly seen with unruptured aneurysms. By contrast, ruptured aneurysms were more likely to have disturbed flow patterns, small impingement regions, and narrow jets.