AJNR. American journal of neuroradiology
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AJNR Am J Neuroradiol · Jan 2011
ReviewPrinciples and limitations of computational algorithms in clinical diffusion tensor MR tractography.
There have been numerous reports documenting the graphic reconstruction of 3D white matter architecture in the human brain by means of diffusion tensor MR tractography. Different from other reviews addressing the physics and clinical applications of DTI, this article reviews the computational principles of tractography algorithms appearing in the literature. ⋯ Subsequently, some advanced techniques attempting to offer improvement in various aspects are briefly introduced, including the increasingly popular research tracking tool using HARDI. The article explains the inherent technical limitations in most of the algorithms reported to date and concludes by providing a reference guideline for formulating routine applications of this important tool to clinical neuroradiology in an objective and reproducible manner.
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AJNR Am J Neuroradiol · Jan 2011
Quantitative characterization of the hemodynamic environment in ruptured and unruptured brain aneurysms.
Hemodynamics are thought to play an important role in the mechanisms of aneurysm pathogenesis, progression, and rupture. The purpose of this study was to define quantitative measures related to qualitative flow characteristics previously analyzed and to investigate their relationship to aneurysm rupture. ⋯ Concentrated inflow streams and WSS distributions with elevated levels of MWSS and low aneurysmal viscous dissipation are statistically associated with a clinical history of prior aneurysm rupture. In contrast, the area and total viscous shear force applied in the aneurysm region subjected to abnormally low WSS levels are not. This study highlights the potential for image-based CFD for investigating aneurysm-evolution mechanisms and for clinical assessment of aneurysm risks.
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AJNR Am J Neuroradiol · Jan 2011
Clinical TrialThe pipeline embolization device for the intracranial treatment of aneurysms trial.
Endoluminal reconstruction with flow diverting devices represents a novel constructive technique for the treatment of cerebral aneurysms. We present the results of the first prospective multicenter trial of a flow-diverting construct for the treatment of intracranial aneurysms. ⋯ Intracranial aneurysm treatment with the PED is technically feasible and can be achieved with a safety profile analogous to that reported for stent-supported coil embolization. PED treatment elicited a very high rate (93%) of complete angiographic occlusion at 6 months in a population of the most challenging anatomic subtypes of cerebral aneurysms.
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AJNR Am J Neuroradiol · Jan 2011
Management of anterior inferior cerebellar artery aneurysms: endovascular treatment and clinical outcome.
AICA aneurysms are rare and a challenge to treat surgically. We present our experience of the angiographic results and the clinical outcomes for 9 AICA aneurysms treated by EVT. ⋯ EVT may provide a feasible and safe option as an alternative, though a microsurgical option is initially considered for the management of AICA aneurysms. Further follow-up and more experience are also necessary.
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AJNR Am J Neuroradiol · Jan 2011
The value of dynamic radiographs in diagnosing painful vertebrae in osteoporotic compression fractures.
Many authors have reported the increase in vertebral body height after vertebroplasty; if the fractured vertebrae are mobile, we should be able to demonstrate their mobility in radiographs. The purpose of this study was to discover the diagnostic value of dynamic radiographs and the percentage of mobile vertebrae in painful VCFs. ⋯ Dynamic (sitting and supine with bolster) radiographs can be valuable in diagnosing painful vertebrae in VCFs. The sensitivity was 0.88 in this study.