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https://www.readbyqxmd.com/read/28620564/moyamoya-syndrome-in-a-child-with-neurofibromatosis-type-1-magnetic-resonance-imaging-as-a-tool-for-clinical-decision-making
#1
Jonathan Mayl, Hanisha Patel, Tushar Chandra
Moyamoya syndrome is a rare cerebrovasculopathy of unknown etiology which is associated with multiple risk factors. Moyamoya was first discovered in Japan and is reported to have an increased prevalence in the Japanese population. The term "Moyamoya" translates into "puff of smoke" and is named after the finding of the collateral cerebral vasculature that develops secondary to occlusion of an internal carotid artery at the entrance into the circle of Willis. This collateral vasculature characterizes the disease...
May 9, 2017: Curēus
https://www.readbyqxmd.com/read/28600011/direct-versus-indirect-bypass-for-moyamoya-disease
#2
REVIEW
Jonathan J Liu, Gary K Steinberg
Moyamoya disease is a progressive occlusive vasculopathy that involves the supraclinoid internal carotid arteries and Circle of Willis, and results in the formation of collateral vessels at the skull base. The progressive nature of this disease leads to cerebral ischemia and sometimes intracerebral hemorrhage. The treatment of moyamoya disease is mainly surgical revascularization, using revascularization techniques that include direct, indirect, and combined strategies. Here we discuss the available options for revascularization as well as our opinions regarding the surgical management of patients with moyamoya disease...
July 2017: Neurosurgery Clinics of North America
https://www.readbyqxmd.com/read/28598141/evaluation-of-cerebral-perfusion-by-contrast-enhanced-ultrasound-at-low-mechanical-index-in-cerebral-ischemia-rat-model
#3
Xiaolei Wang, Bo Liu, Jiongou Liu, Aitong Sun, Yan Cui, Rui Xiao, Chunyang Li
BACKGROUND: No data is available for brain low mechanical index (low-MI) contrast-enhanced ultrasound (CEUS). This study aimed to assess low-MI CEUS for cerebral ischemia in rats. METHODS: Twenty adult Wistar rats were divided to the brain ischemia (n=12) and sham (n=8) groups. A Logiq E9 (GE; ML6-15 probe) was used. Bolus injection of SonoVue (Bracco) at 3.6 ml/kg was performed. Cerebral perfusion was evaluated using time to peak (TTP) and area under the curve (AUC) of time-intensity curves (TIC)...
June 9, 2017: International Angiology: a Journal of the International Union of Angiology
https://www.readbyqxmd.com/read/28574313/rationale-for-graft-selection-in-patients-with-complex-internal-carotid-artery-aneurysms-treated-with-extracranial-to-intracranial-high-flow-bypass-and-therapeutic-internal-carotid-artery-occlusion
#4
Hidetoshi Matsukawa, Shiro Miyata, Toshiyuki Tsuboi, Kosumo Noda, Nakao Ota, Osamu Takahashi, Rihee Takeda, Sadahisa Tokuda, Hiroyasu Kamiyama, Rokuya Tanikawa
OBJECTIVE After internal carotid artery (ICA) sacrifice without revascularization for complex aneurysms, ischemic complications can occur. In addition, hemodynamic alterations in the circle of Willis create conditions conducive to the formation of de novo aneurysms or the enlargement of existing untreated aneurysms. Therefore, the revascularization technique remains indispensable. Because vessel sizes and the development of collateral circulation are different in each patient, the ideal graft size to prevent low flow-related ischemic complications (LRICs) in external carotid artery (ECA)-middle cerebral artery (MCA) bypass with therapeutic ICA occlusion (ICAO) has not been well established...
June 2, 2017: Journal of Neurosurgery
https://www.readbyqxmd.com/read/28554037/fluid-structure-interaction-simulation-of-a-cerebral-aneurysm-effects-of-endovascular-coiling-treatment-and-aneurysm-wall-thickening
#5
Amir Shamloo, Milad Azimi Nejad, Milad Saeedi
In the present study, we investigate the effect of the hemodynamic factors of the blood flow on the cerebral aneurysms. To this end, a hypothetical geometry of the aneurysm in the circle of Willis, located in the bifurcation point of the anterior cerebral artery (ACA) and anterior communicating artery (ACoA) is modeled in a three-dimensional manner. Three cases are chosen in the current study: an untreated thin wall (first case), untreated thick wall (second case), and a treated aneurysm (third case). The effect of increasing the aneurysm wall thickness on the deformation and stress distribution of the walls are studied...
May 14, 2017: Journal of the Mechanical Behavior of Biomedical Materials
https://www.readbyqxmd.com/read/28550100/an-alternative-surgical-approach-reduces-variability-following-filament-induction-of-experimental-stroke-in-mice
#6
M Trotman-Lucas, M E Kelly, J Janus, R Fern, C L Gibson
Animal models are critical for understanding the pathology of stroke and investigating potential treatments. However, in vivo stroke models are associated, particularly in mice, with high variability in lesion volume. We investigated whether a surgical refinement where reperfusion is not reliant on the Circle of Willis reduced outcome variability. Mice underwent 60 minutes of transient middle cerebral artery occlusion avoiding ligation of the external carotid artery. During reperfusion the common carotid artery was either ligated (standard approach), or it was repaired to allow re-establishment of blood flow through the common carotid artery...
May 26, 2017: Disease Models & Mechanisms
https://www.readbyqxmd.com/read/28530158/analyzing-circle-of-willis-blood-flow-in-ischemic-stroke-patients-through-3d-stroke-arterial-flow-estimation
#7
Aichi Chien, Fernando Viñuela
Background The objective of ischemic stroke (IS) treatment is to achieve revascularization in cerebral arteries to restore blood flow. However, there is no available method to extract arterial flow data from clinical CTA images. We developed 3D Stroke Arterial Flow Estimation (SAFE), which provides blood flow data throughout the Circle of Willis based on 3D CTA and allows comparison of arterial flow distribution in the brain. Methods We implemented a newly developed 3D vascular reconstruction algorithm for clinical stroke CTA images...
January 1, 2017: Interventional Neuroradiology
https://www.readbyqxmd.com/read/28500366/comparison-of-3d-magnetic-resonance-imaging-and-digital-subtraction-angiography-for-intracranial-artery-stenosis
#8
Ji Eun Park, Seung Chai Jung, Sang Hun Lee, Ji Young Jeon, Ji Ye Lee, Ho Sung Kim, Choong-Gon Choi, Sang Joon Kim, Deok Hee Lee, Seon-Ok Kim, Sun U Kwon, Dong-Wha Kang, Jong S Kim
OBJECTIVES: To compare three-dimensional high-resolution magnetic resonance imaging (3D HR-MRI) and digital subtraction angiography (DSA) for diagnosing and evaluating stenosis in the entire circle of Willis. METHODS: The study included 516 intracranial arteries from 43 patients with intracranial artery stenosis (ICAS) who underwent both 3D HR-MRI and DSA within 1 month. Two readers independently diagnosed atherosclerosis, dissection, moyamoya disease and vasculitis, rated their diagnostic confidence for each vessel and measured the luminal diameters...
May 12, 2017: European Radiology
https://www.readbyqxmd.com/read/28465268/intracranial-blood-flow-changes-in-patients-with-high-grade-severe-carotid-artery-stenosis-after-stenting
#9
Lei Huang, Wenjie Cao, Liang Ge, Gang Lu, Xiaolong Zhang, Daoying Geng
OBJECTIVE: We investigated whether the cerebral hemodynamic changes of pre- and poststenting in patients with severe carotid stenosis differ by stenosis grades. MATERIALS AND METHODS: We prospectively recruited patients who underwent carotid artery stenting (CAS) after acute ischemic stroke from June 2014 to December 2015. We compared the mean relative cerebral blood flow changes (rCBF) (measured by whole-brain computed tomography [CT] perfusion) pre- and poststenting in patients with high-grade severe stenosis (HGSS 90%-99%) versus patients with low-grade severe stenosis (LGSS 70%-89%)...
April 29, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/28439614/internal-carotid-artery-stenosis-and-collateral-recruitment-in-stroke-patients
#10
Jan W Dankbaar, Kelly G P Kerckhoffs, Alexander D Horsch, Irene C van der Schaaf, L Jaap Kappelle, Birgitta K Velthuis
PURPOSE: Leptomeningeal collaterals improve outcome in stroke patients. There is great individual variability in their extent. Internal carotid artery (ICA) stenosis may lead to more extensive recruitment of leptomeningeal collaterals. The purpose of this study was to evaluate the association of pre-existing ICA stenosis with leptomeningeal collateral filling visualized with computed tomography perfusion (CTP). METHODS: From a prospective acute ischemic stroke cohort, patients were included with an M1 middle cerebral artery (MCA) occlusion and absent ipsilateral, extracranial ICA occlusion...
April 24, 2017: Clinical Neuroradiology
https://www.readbyqxmd.com/read/28439406/angiographic-anatomy-of-the-extracranial-and-intracranial-portions-of-the-internal-carotid-arteries-in-donkeys
#11
Nurul Hayah Khairuddin, Martin Sullivan, Patrick J Pollock
BACKGROUND: In horses, the extracranial and intracranial pathway of the internal carotid artery has been described. The extracranial pathway of the internal carotid artery begins at the carotid termination and runs on the dorsal surface of the medial compartment of the guttural pouch. Thereafter the internal carotid artery passes through the foramen lacerum to continue intracranially, forming part of the rostrolateral quadrants of the cerebral arterial circle (Circle of Willis). The objectives of this study were to define and record the anatomy of the carotid arterial tree and the internal carotid artery in donkeys using angiographic techniques...
2017: Irish Veterinary Journal
https://www.readbyqxmd.com/read/28412828/magnetic-resonance-angiographic-study-of-anatomic-variations-of-the-circle-of-willis-in-a-population-in-tehran
#12
Bahman Jalali Kondori, Fateme Azemati, Sonia Dadseresht
BACKGROUND AND OBJECTIVES: The circle of Willis, an anastomotic polygon at the base of the brain, forms an important collateral network to maintain cerebral blood perfusion. The aim of this study was to investigate different anatomic variations of the circle of Willis and their prevalence. METHODS: This cross-sectional study was conducted on 525 healthy participants including 205 men and 320 women. The mean age of the patients was 51.5 years. Three-dimensional time-of-flight magnetic resonance angiography (3D-TOF MRA) technique was used...
April 2017: Archives of Iranian Medicine
https://www.readbyqxmd.com/read/28396980/median-pericallosal-artery-with-double-proximal-origin-case-report-and-clinical-consideration
#13
Maryna A Kornieieva, Azmy M Hadidy, Suzan H Hinno
A 76-year-old male patient underwent magnetic resonance angiography of the head and neck vessels due to a recent incident of transitory ischemic attack. Cerebral angiogram uncovered the double proximal origin of the median unpaired pericallosal artery from the duplicated anterior communicating complex. The vessel curved around the corpus callosum and irrigated the paracentral lobule and the medial parietal cortical areas. The main trunks of the anterior cerebral arteries showed a branching pattern of the marginal callosal arteries, supplying orbital and frontal territories...
April 10, 2017: Surgical and Radiologic Anatomy: SRA
https://www.readbyqxmd.com/read/28386716/importance-of-variants-in-cerebrovascular-anatomy-for-potential-retrograde-embolization-in-cryptogenic-stroke
#14
Michael Markl, Edouard Semaan, LeRoy Stromberg, James Carr, Shyam Prabhakaran, Jeremy Collins
OBJECTIVES: To test the hypothesis that variants in cerebrovascular anatomy will affect the number of patients demonstrating a plausible retrograde embolization mechanism from plaques in the descending aorta (DAo). METHODS: Thirty-five patients (aged 63 ± 17 years) with cryptogenic stroke underwent 4D flow MRI for the assessment of aortic 3D blood flow and MR angiography for the evaluation of circle of Willis, posterior circulation, and aortic arch architecture...
April 6, 2017: European Radiology
https://www.readbyqxmd.com/read/28382440/tetralogy-of-fallot-surgical-repair-shunt-configurations-ductus-arteriosus-and-the-circle-of-willis
#15
Senol Piskin, Gozde Unal, Ahmet Arnaz, Tayyar Sarioglu, Kerem Pekkan
In this study, hemodynamic performance of three novel shunt configurations that are considered for the surgical repair of tetralogy of Fallot (TOF) disease are investigated in detail. Clinical experience suggests that the shunt location, connecting angle, and its diameter can influence the post-operative physiology and the neurodevelopment of the neonatal patient. An experimentally validated second order computational fluid dynamics (CFD) solver and a parametric neonatal diseased great artery model that incorporates the ductus arteriosus (DA) and the full patient-specific circle of Willis (CoW) are employed...
June 2017: Cardiovascular Engineering and Technology
https://www.readbyqxmd.com/read/28366069/the-circle-of-willis-predicts-the-antihypertensive-effects-of-carotid-artery-stenting
#16
RANDOMIZED CONTROLLED TRIAL
David R Santiago-Dieppa, Brian R Hirshman, Arvin Wali, J Scott Pannell, Yasaman Alam, Scott Olson, Vincent J Cheung, Jeffrey A Steinberg, Mihir Gupta, Alexander A Khalessi
OBJECTIVE Carotid artery stenting (CAS) has antihypertensive effects, but the durability and degree of this response remain variable. The authors propose that this clinical variability is a function of the presence or absence of a complete circle of Willis (COW). Incomplete COWs perfuse through a higher-resistance pial collateral pathway, and therefore patients may require a higher mean arterial pressure (MAP). Carotid artery revascularization in these patients would reduce the end-organ collateral demand that has been hypothesized to drive the MAP response...
April 2017: Neurosurgical Focus
https://www.readbyqxmd.com/read/28350198/subarachnoid-hemorrhage-induced-block-of-cerebrospinal-fluid-flow-role-of-brain-coagulation-factor-iii-tissue-factor
#17
Eugene V Golanov, Evgeniy I Bovshik, Kelvin K Wong, Robia G Pautler, Chase H Foster, Richard G Federley, Jonathan Y Zhang, James Mancuso, Stephen Tc Wong, Gavin W Britz
Subarachnoid hemorrhage (SAH) in 95% of cases results in long-term disabilities due to brain damage, pathogenesis of which remains uncertain. Hindrance of cerebrospinal fluid (CSF) circulation along glymphatic pathways is a possible mechanism interrupting drainage of damaging substances from subarachnoid space and parenchyma. We explored changes in CSF circulation at different time following SAH and possible role of brain tissue factor (TF). Fluorescent solute and fluorescent microspheres injected into cisterna magna were used to track CSF flow in mice...
January 1, 2017: Journal of Cerebral Blood Flow and Metabolism
https://www.readbyqxmd.com/read/28341559/-moyamoya-disease-associated-with-kidney-angiodysplasia-in-a-child
#18
A Dibi, Z Maana, F Jabourik, A Bentahila
INTRODUCTION: Moyamoya disease is a progressive, chronic occlusive vascular disease of the circle of Willis arteries leading to the development of collateral circulation to compensate the occlusion. CASE REPORT: An 11-year-old girl presented an abrupt loss of consciousness and a right-sided motor deficit. Clinical examination found hypertension with 220/120mmHg arterial blood pressure. Brain magnetic resonance imaging showed a large left hemispheric ischemic lesion...
May 2017: Archives de Pédiatrie: Organe Officiel de la Sociéte Française de Pédiatrie
https://www.readbyqxmd.com/read/28327941/degree-of-vascular-encasement-in-sphenoid-wing-meningiomas-predicts-postoperative-ischemic-complications
#19
D Jay McCracken, Raymond A Higginbotham, Jason H Boulter, Yuan Liu, John A Wells, Sameer H Halani, Amit M Saindane, Nelson M Oyesiku, Daniel L Barrow, Jeffrey J Olson
BACKGROUND: Sphenoid wing meningiomas (SWMs) can encase arteries of the circle of Willis, increasing their susceptibility to intraoperative vascular injury and severe ischemic complications. OBJECTIVE: To demonstrate the effect of circumferential vascular encasement in SWM on postoperative ischemia. METHODS: A retrospective review of 75 patients surgically treated for SWM from 2009 to 2015 was undertaken to determine the degree of circumferential vascular encasement (0°-360°) as assessed by preoperative magnetic resonance imaging (MRI)...
June 1, 2017: Neurosurgery
https://www.readbyqxmd.com/read/28303205/aneurysm-of-azygos-anterior-cerebral-artery-associated-with-falcine-meningioma-case-report-and-review-of-the-literature
#20
Lucas C Meguins, Raquel C T Hidalgo, Antônio R Spotti, Dionei F de Morais
BACKGROUND: The azygos anterior cerebral artery (ACA) is an uncommon intracranial vascular anomaly of the circle of Willis. Identification of aneurysm from azygos ACA with anterior falcine meningioma is an extremely rare association. The aim of the present study is to report the case of an adult female with a ruptured aneurysm from azygos ACA in association with an anterior falcine meningioma. CASE DESCRIPTION: A 65-year-old female was admitted in the Emergency Department reporting sudden onset of severe headache...
2017: Surgical Neurology International
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