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Intracranial Aneurysms (intracranial + aneurysms)
Selected AbstractsThromboembolism and Rebleeding Paradox in Stent-Assisted Embolization for Intracranial AneurysmsJOURNAL OF NEUROIMAGING, Issue 2 2010Ramachandra P. Tummula MD No abstract is available for this article. [source] CMR 2005: 8.07: Real-time assessment and off-line quantification of flow dynamics in intracranial aneurysms using intra-operative contrast-specified ultrasoundCONTRAST MEDIA & MOLECULAR IMAGING, Issue 2 2006T. Hölscher [source] Ruptured symptomatic internal carotid artery dorsal wall aneurysm with rapid configurational change.EUROPEAN JOURNAL OF NEUROLOGY, Issue 10 2010Clinical experience, management outcome: an original article Background:, Aneurysms located at non-branching sites, protruding from the dorsal wall of the supraclinoid internal carotid artery (ICA) with rapid configurational changes, were retrospectively reviewed in effort to identify and characterize these high-risk aneurysms. Methods:, A total of 447 patients with 491 intracranial aneurysms were treated from March 2005 to August 2008, and of these, eight patients had ICA dorsal wall aneurysms. Four of them suffered subarachnoid hemorrhage (SAH), and all had aneurysms undergoing rapid configuration changes during the treatment course. Digital subtraction cerebral angiography (DSA) performed soon after the SAH events. Data analyzed were patient age, sex, Hunt and Kosnik grade, time interval from first DSA to second DSA, aneurysm treatment, and modified Rankin scale score after treatment for 3 months. Success or failure of therapeutic management was examined among the patients. Results:, Digital subtraction cerebral angiography showed only lesions with small bulges in the dorsal walls of the ICAs. However, the patients underwent DSA again for re-bleeding or for post-treatment follow-up, confirming the SAH source. ICA dorsal wall aneurysms with rapid growth and configurational changes were found on subsequent DSA studies. Conclusions:, Among the four patients, ICA dorsal wall aneurysms underwent rapid growth with configurational change from a blister type to a saccular type despite different management. ICA trapping including the lesion segment can be considered as the first treatment option if the balloon occlusion test (BOT) is successful. If a BOT is not tolerated by the patient, extracranial,intracranial bypass revascularization surgery with endovascular ICA occlusion is another treatment option. [source] Matrix metalloproteinases 2 and 9 in human atherosclerotic and non-atherosclerotic cerebral aneurysmsEUROPEAN JOURNAL OF NEUROLOGY, Issue 10 2006J. Caird Matrix metalloproteinases 2 and 9 (MMP 2 and -9) have been implicated in the pathogenesis of atherosclerosis and aneurysm formation. The goal of the study was to establish the role of these metalloproteinases in both human atherosclerotic and non-atherosclerotic cerebral aneurysms. Eleven cerebral aneurysms (four atherosclerotic, seven non-atherosclerotic) were immunohistochemically stained for MMP 2 and -9. As controls, atherosclerotic and normal Circle of Willis arteries were similarly immunostained. All specimens were retrieved at autopsy and were paraffin-embedded. In order to evaluate the real MMP 2 and -9 activities, gelatin zymography was also performed in only two available specimens of non-atherosclerotic intracranial aneurysms, because of the relative unavailability of fresh intracranial aneurysm tissue (i.e. reluctance to excise the aneurysm fundus at surgery). Our data establish that MMP 2 and -9 were expressed minimally or not at all in normal Circle of Willis arteries but were strongly expressed in medial smooth muscle cells of atherosclerotic Circle of Willis arteries. In the aneurysm group, both MMP 2 and -9 were strongly expressed in the atherosclerotic aneurysms, but MMP 2 alone was detected in the non-atherosclerotic aneurysms. Zymography revealed a weak enzyme activity correlating to MMP 9 standard recombinant protein. MMP 2 activity was not demonstrated in either specimen. This study shows that the expression of MMP 2 and -9 is associated with atherosclerosis, be it in aneurysmal or non-aneurysmal cerebral vessels but MMP 2 appears to be specifically expressed in aneurysms devoid of atherosclerosis perhaps suggesting a pathogenic role for MMP 2 in the alteration of the extracellular matrix of cerebral arteries during aneurysm formation. [source] Hemodynamic analysis of intracranial aneurysms with moving parent arteries: Basilar tip aneurysmsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 10 2010Daniel M. Sforza Abstract The effects of parent artery motion on the hemodynamics of basilar tip saccular aneurysms and its potential effect on aneurysm rupture were studied. The aneurysm and parent artery motions in two patients were determined from cine loops of dynamic angiographies. The oscillatory motion amplitude was quantified by registering the frames. Patient-specific computational fluid dynamics (CFD) models of both aneurysms were constructed from 3D rotational angiography images. Two CFD calculations were performed for each patient, corresponding to static and moving models. The motion estimated from the dynamic images was used to move the surface grid points in the moving model. Visualizations from the simulations were compared for wall shear stress (WSS), velocity profiles, and streamlines. In both patients, a rigid oscillation of the aneurysm and basilar artery in the anterio-posterior direction was observed and measured. The distribution of WSS was nearly identical between the models of each patient, as well as major intra-aneurysmal flow structures, inflow jets, and regions of impingement. The motion observed in pulsating intracranial vasculature does not have a major impact on intra-aneurysmal hemodynamic variables. Parent artery motion is unlikely to be a risk factor for increased risk of aneurysmal rupture. Copyright © 2010 John Wiley & Sons, Ltd. [source] MRA of intracranial aneurysms embolized with platinum coils: A vascular phantom study at 1.5T and 3TJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2008Shingo Kakeda Abstract Purpose To analyze the influence of matrix and echo time (TE) of three-dimensional time-of-flight (3D TOF) magnetic resonance angiography (MRA) on the depiction of residual flow in aneurysms embolized with platinum coils at 1.5T and 3T. Materials and Methods A simulated intracranial aneurysm of the vascular phantom was loosely packed to maintain the patency of some residual aneurysmal lumen with platinum coils and connected to an electromagnetic flow pump with pulsatile flow. MRAs were obtained altering the matrix and TE of 3D TOF sequences at 1.5T and 3T. Results The increased spatial resolution and the shorter TE offered better image quality at 3T. For the depiction of an aneurysm remnant, the high-spatial-resolution 3T MRA (matrix size of 384 × 224 and 512 × 256) with a short TE of ,3.3 msec were superior to the 1.5T MRA obtained with any sequences. Conclusion 3T MRA is superior to 1.5T MRA for the assessment of aneurysms embolized with platinum coils; the combination of the 512 × 256 matrix and short TE (3.3 msec or less) seems feasible at 3T. J. Magn. Reson. Imaging 2008;28:13,20. © 2008 Wiley-Liss, Inc. [source] Follow up of coiled intracranial aneurysms with standard resolution and higher resolution magnetic resonance angiographyJOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 1 2008S Dupre Summary Time-of-flight magnetic resonance angiography is a non-invasive alternative to digital subtraction angiography (DSA) for follow up of coiled intracranial aneurysms. Standard cranial MRA protocols are a compromise between spatial resolution and imaging time. This study compares a standard resolution MRA protocol with a protocol at higher spatial resolution MRA (HR-MRA) in 21 follow-up occasions in 17 coiled aneurysms in 15 patients. Images were reviewed for presence of residual or recurrent aneurysm and compared with DSA as the gold standard. Aneurysm flow signal on standard resolution MRA differed significantly from HR-MRA in 6/21 cases (P = 0.02) and DSA in 6/21 cases (P = 0.02). HR-MRA had 100% concordance with DSA (P = 1.0). In this study, three-dimensional time-of-flight magnetic resonance angiography carried out at standard resolution is inadequate for follow up of coiled intracranial aneurysms. HR-MRA is comparable to DSA for detection of aneurysm recurrence. [source] Screening for intracranial aneurysms in autosomal dominant polycystic kidney diseaseNEPHROLOGY, Issue 4 2003Review Article SUMMARY: Screening patients with autosomal dominant polycystic kidney disease (ADPKD) for asymptomatic intracranial aneurysms has been proposed as a method of reducing the morbidity and mortality associated with aneurysm rupture. However, recent studies have shown lower spontaneous rupture rates of small aneurysms and higher risks of significant complications with interventions than previously reported. Risk-benefit analysis has not demonstrated any benefit of screening ADPKD patients without a history of subarachnoid haemorrhage (SAH) for intracranial aneurysms, and has suggested that screening might cause harm. [source] Calcified giant intracranial aneurysmsANZ JOURNAL OF SURGERY, Issue 1-2 2010BscMed(Hons), Ju Yong Cheong MBBS No abstract is available for this article. [source] Cerebellar arteriovenous malformation and vertebral artery aneurysm in a CADASIL patientACTA NEUROLOGICA SCANDINAVICA, Issue 1 2006F. Pescini The presence of large vessels malformations has not been reported in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). We describe a CADASIL patient in whom a brain cerebellar arteriovenous malformation was revealed by magnetic resonance (MR) imaging. An MR angiogram documented also an aneurysm along the right intracranial vertebral artery at the junction with the posterior,inferior cerebellar artery. The aneurysm was successfully treated by means of endovascular coil embolization. No neurological complication occurred in our patient during the angiographic procedure. In this case, in addition to an incidental coexistence of CADASIL and large vessels abnormalities, a causal role of the Notch pathway alteration could be hypothesized. Dysregulation of the Notch pathway is linked to several human diseases besides CADASIL. In one of these (the Alagille syndrome) intracranial aneurysms are reported. This hypothesis contrasts however with the absence of similar reports in other CADASIL cases and needs corroboration in large series. [source] Ultrasound contrast enhancing agents in neurosonology: principles, methods,future possibilitiesACTA NEUROLOGICA SCANDINAVICA, Issue 1 2000D. W. Droste Objectives, Ultrasound of the brain supplying arteries is a standard diagnostic procedure in patients with suspected and definite acute and chronic cerebrovascular occlusive disease. Anatomical and pathological limitations led to the development of echocontrast agents which are able to survive pulmonary and capillary transit and improve the echogenicity of the flowing blood. Material and Methods, This article reviews present and future applications of echocontrast agents in conjunction with personal experiences. Results, Currently, echocontrast is used for the differentiation of internal carotid artery occlusion and pseudoocclusion, better delineation of the maximal narrowing in high-grade stenoses, and better visualization of the extracranial vertebral artery and its collaterals. Transcranial applications include the insufficient foraminal or temporal window, assessment of arteriovenous malformations, thrombosis of cerebral veins and sinuses, and intracranial aneurysms. The use of echocontrast can have direct diagnostic and therapeutic consequences. Harmonic imaging, perfusion imaging, stimulated acoustic emission, and drug delivery are possible future domains of the technique. Discussion, Besides the support of conventional neurovascular ultrasound in poor examination conditions due to the patients' anatomy or pathology, echocontrast agents may allow for novel applications in the diagnosis and treatment of cerebrovascular patients. [source] | ||||||||||