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chiari malformation flow

Roger Schmidt Brock, Mario Augusto Taricco, Matheus Fernandes de Oliveira, Marcelo de Lima Oliveira, Manoel Jacobsen Teixeira, Edson Bor-Seng-Shu
INTRODUCTION: Chiari malformation Type I (CM) is the main congenital malformation disease of the craniovertebral junction. The ideal surgical treatment is still controversial. Invasive procedures inside CSF space and associated with dural repair are considered the gold standard, however a less invasive surgery with isolated bone decompression without dural opening may be possible in selected patients.. Our study evaluates the efficacy of intra-operative CSF flow measurement with ultrasonography (USG) as a determining parameter in the selection of these patients...
February 9, 2017: World Neurosurgery
Tao Fan, HaiJun Zhao, XinGang Zhao, Cong Liang, YinQian Wang, QiFei Gai
Chiari I malformation has been shown to present different cerebrospinal fluid (CSF) flow patterns at the cranial-vertebral junction (CVJ). Posterior fossa decompression is the first-line treatment for symptomatic Chiari I malformation. However, there is still controversy on the indication and selection of decompression procedures. This research aims to investigate the clinical indications, outcomes, and complications of the decompression procedures as alternative treatments for Chiari I malformation, based on the different CSF flow patterns at the cranial-vertebral junction...
February 9, 2017: Neurosurgical Review
Susan P Knowler, Chloe Cross, Sandra Griffiths, Angus K McFadyen, Jelena Jovanovik, Anna Tauro, Zoha Kibar, Colin J Driver, Roberto M La Ragione, Clare Rusbridge
OBJECTIVES: To characterise the symptomatic phenotype of Chiari-like malformation (CM), secondary syringomyelia (SM) and brachycephaly in the Cavalier King Charles Spaniel using morphometric measurements on mid-sagittal Magnetic Resonance images (MRI) of the brain and craniocervical junction. METHODS: This retrospective study, based on a previous quantitative analysis in the Griffon Bruxellois (GB), used 24 measurements taken on 130 T1-weighted MRI of hindbrain and cervical region...
2017: PloS One
Kerem Mazhar Ozsoy, Kadir Oktay, Nuri Eralp Cetinalp, Yurdal Gezercan, Tahsin Erman
AIM: The aim of this study was to define the role of phase-contrast cine magnetic resonance imaging in deciding the therapeutic strategy and underlying pathophysiology resulting in syrinx formation in patients with Chiari type 0 malformation. MATERIAL AND METHODS: Seven patients admitted to our clinic with diagnosis of Chiari 0 malformations during the period January 2005 to July 2016 were enrolled in the study. All patients underwent a detailed preoperative neurological examination...
December 14, 2016: Turkish Neurosurgery
Erik C Brown, Kunal Gupta, Christina Sayama
Lateral meningocele syndrome (LMS) is a rare genetic connective tissue disorder. It is associated with morphological changes similar to those of other connective tissue disorders, with the unique distinction of multiple, often bilateral and large, lateral meningoceles herniating through the spinal foramina. In some cases, these lateral meningoceles can cause pain and discomfort due to their presence within retroperitoneal tissues or cause direct compression of the spinal nerve root exiting the foramen; in some cases compression may also involve motor weakness...
February 2017: Journal of Neurosurgery. Pediatrics
Kartik Jain, Geir Ringstad, Per-Kristian Eide, Kent-André Mardal
Obstruction to the cerebrospinal fluid (CSF) outflow caused by the herniation of cerebellar tonsils as a result of Chiari malformation type I leads to altered CSF hydrodynamics. This contribution explores the minutest characteristics of the CSF hydrodynamics in cervical subarachnoid spaces (SAS) of a healthy subject and two Chiari patients by performing highly resolved direct numerical simulation. The Lattice Boltzmann method is used for the simulations due to its scalability on modern supercomputers that allow us to simulate up to  ∼ 10(9) cells while resolving the Kolmogorov microscales...
November 10, 2016: International Journal for Numerical Methods in Biomedical Engineering
Radek Frič, Erika Kristina Lindstrøm, Geir Andre Ringstad, Kent-André Mardal, Per Kristian Eide
BACKGROUND: In symptomatic Chiari malformation type 1 (CMI), impaired intracranial compliance (ICC) is associated with an increased cranio-spinal pulsatile pressure gradient. Phase-contrast magnetic resonance imaging (MRI) represents a non-invasive modality for the assessment of the pulse pressure gradient at the cranio-cervical junction (CCJ). We wished to explore how the MRI-derived pulse pressure gradient (MRI-dP) compares with invasively measured pulsatile intracranial pressure (ICP) in CMI, and with healthy controls...
October 14, 2016: Acta Neurochirurgica
Karen-Helene Støverud, Hans Petter Langtangen, Geir Andre Ringstad, Per Kristian Eide, Kent-Andre Mardal
PURPOSE: Previous computational fluid dynamics (CFD) studies have demonstrated that the Chiari malformation is associated with abnormal cerebrospinal fluid (CSF) flow in the cervical part of the subarachnoid space (SAS), but the flow in the SAS of the posterior cranial fossa has received little attention. This study extends previous modelling efforts by including the cerebellomedullary cistern, pontine cistern, and 4th ventricle in addition to the cervical subarachnoid space. METHODS: The study included one healthy control, Con1, and two patients with Chiari I malformation, P1 and P2...
2016: PloS One
Woon Tak Yuh, Chi Heon Kim, Chun Kee Chung, Hyun-Jib Kim, Tae-Ahn Jahng, Sung Bae Park
OBJECTIVE: The pathophysiology of idiopathic Chiari malformation (CM) type 1 is disturbance of free cerebrospinal fluid (CSF) flow and restoration of normal CSF flow is the mainstay of treatment. Additional migration of the medulla oblongata in pediatric patients is referred to as CM type 1.5, but its significance in adult patients is unknown. This study is to compare surgical outcomes of adult idiopathic CM type 1.5 with that of type 1. METHODS: Thirty-eight consecutive adult patients (M : F=11 : 27; median, 33...
September 2016: Journal of Korean Neurosurgical Society
Helen Williams
It is proposed that negative central nervous system (CNS) pressure is one of the filling mechanisms of the fluid spaces of the CNS. Negative CNS pressure is caused by the combination of gravitational force and body movement. The venous system imposes pressure fluctuations on the CNS due to changes in posture and body cavity pressure. It is proposed here that filling of veins, arteries and cerebrospinal (CSF) spaces are all assisted by negative CNS pressure. Hyperemia in the CNS in response to pressure changes with movement was described in the first part of this hypothesis...
September 2016: Medical Hypotheses
Noam Alperin, James Ryan Loftus, Ahmet M Bagci, Sang H Lee, Carlos J Oliu, Ashish H Shah, Barth A Green
OBJECTIVE This study identifies quantitative imaging-based measures in patients with Chiari malformation Type I (CM-I) that are associated with positive outcomes after suboccipital decompression with duraplasty. METHODS Fifteen patients in whom CM-I was newly diagnosed underwent MRI preoperatively and 3 months postoperatively. More than 20 previously described morphological and physiological parameters were derived to assess quantitatively the impact of surgery. Postsurgical clinical outcomes were assessed in 2 ways, based on resolution of the patient's chief complaint and using a modified Chicago Chiari Outcome Scale (CCOS)...
January 2017: Journal of Neurosurgery. Spine
Parag P Sayal, Arif Zafar, Thomas A Carroll
In a certain group of patients with syringomyelia, even with the advent of sophisticated magnetic resonance imaging (MRI), no associated abnormality or cerebrospinal fluid (CSF) block is easily identified. This type of syringomyelia is often termed idiopathic. Current literature has less than 10 reports of arachnoid webs to be the causative factor. We present our experience in the management of two cases of syringomyelia secondary to arachnoid webs. Both our patients presented with progressive neurological deterioration with MRI scans demonstrating cervical/thoracic syrinx without Chiari malformation or low-lying cord...
April 2016: Journal of Craniovertebral Junction and Spine
Sébastien Richard, Lisa Humbertjean, Gioia Mione, Marc Braun, Emmanuelle Schmitt, Sophie Colnat-Coulbois
BACKGROUND: Syringomyelia due to intracranial hypotension is rarely described. As a consequence, intracranial hypotension is less recognized as a potential cause of syringomyelia or mistaken with Chiari type 1 malformation. The pathogeny is poorly understood, and we lack diagnostic and therapeutic strategies for this particular setting. CASE DESCRIPTION: We describe a 45-year-old patient who developed syringomyelia after about 10 years of undiagnosed intracranial hypotension caused by traumatic C6 cerebrospinal fluid (CSF) leak...
July 2016: World Neurosurgery
Erin J Kelly, Shinya Yamada
This article provides an overview of magnetic resonance imaging (MRI) techniques used to assess cerebrospinal fluid (CSF) movement in the central nervous system (CNS), including Phase-Contrast (PC), Time-Spatial Labeling Inversion Pulse, and simultaneous multi slice echo planar phase contrast imaging. These techniques have been used to assess CSF movement in the CNS under normal and pathophysiological situations. PC can quantitatively measure stroke volume in selected regions, particularly the aqueduct of Sylvius, as synchronized to the heartbeat...
April 2016: Seminars in Ultrasound, CT, and MR
Soroush Heidari Pahlavian, Alexander C Bunck, Suraj Thyagaraj, Daniel Giese, Francis Loth, Dennis M Hedderich, Jan Robert Kröger, Bryn A Martin
Abnormal alterations in cerebrospinal fluid (CSF) flow are thought to play an important role in pathophysiology of various craniospinal disorders such as hydrocephalus and Chiari malformation. Three directional phase contrast MRI (4D Flow) has been proposed as one method for quantification of the CSF dynamics in healthy and disease states, but prior to further implementation of this technique, its accuracy in measuring CSF velocity magnitude and distribution must be evaluated. In this study, an MR-compatible experimental platform was developed based on an anatomically detailed 3D printed model of the cervical subarachnoid space and subject specific flow boundary conditions...
November 2016: Annals of Biomedical Engineering
J Rajiv Bapuraj, Frank J Londy, Nader Delavari, Cormac O Maher, Hugh J L Garton, Bryn A Martin, Karin M Muraszko, El-Sayed H Ibrahim, Douglas J Quint
PURPOSE: To assess the effects of cerebrospinal fluid (CSF) bidirectional motion in Chiari malformation type I (CMI), we monitored CSF velocity amplitudes on phase contrast MRI (PC-MRI) in patients before and after surgery; and in healthy volunteers. MATERIALS AND METHODS: 10 pediatric volunteers and 10 CMI patients participated in this study. CMI patients underwent PC-MRI scans before and approximately 14 months following surgery. Two parameters-amplitude of mean velocity (AMV) and amplitude of peak velocity (APV) of CSF-were derived from the data...
August 2016: Journal of Magnetic Resonance Imaging: JMRI
R Shane Tubbs, Christina M Kirkpatrick, Elias Rizk, Joshua J Chern, Rod J Oskouian, W Jerry Oakes
BACKGROUND: In the past, diagnosis of the Chiari I malformation has primarily been made on midsagittal MRI. We hypothesized that based on the frequent presentation of opisthotonos in patients with hindbrain hernia (primarily Chiari II malformation but sometimes Chiari I malformation) that the hyperextension might be a compensatory technique used by such patients to bring the cerebellar tonsils up out of the cervical spine. PATIENTS AND METHODS: This prospective study reviewed imaging of patients with Chiari I malformation who underwent flexion/extension MRI for evaluation of their hindbrain herniation...
March 2016: Child's Nervous System: ChNS: Official Journal of the International Society for Pediatric Neurosurgery
Vannessa Leung, John S Magnussen, Marcus A Stoodley, Lynne E Bilston
OBJECTIVE: The pathogenesis of syringomyelia associated with Chiari malformation type I (CM-I) is unclear. Theories of pathogenesis suggest the cerebellar tonsils may obstruct CSF flow or alter pressure gradients, or their motion might act as a piston to increase CSF pressure in the spinal subarachnoid space. This study was performed to measure cerebellar tonsillar and hindbrain motion in CM-I and assess the potential contributions to syrinx formation. METHODS: Sixty-four CM-I patients and 25 controls were retrospectively selected from a clinical database, and all subjects had undergone cardiac-gated cine balanced fast-field echo MRI...
April 2016: Journal of Neurosurgery. Spine
Bryn A Martin, Theresia I Yiallourou, Soroush Heidari Pahlavian, Suraj Thyagaraj, Alexander C Bunck, Francis Loth, Daniel B Sheffer, Jan Robert Kröger, Nikolaos Stergiopulos
For the first time, inter-operator dependence of MRI based computational fluid dynamics (CFD) modeling of cerebrospinal fluid (CSF) in the cervical spinal subarachnoid space (SSS) is evaluated. In vivo MRI flow measurements and anatomy MRI images were obtained at the cervico-medullary junction of a healthy subject and a Chiari I malformation patient. 3D anatomies of the SSS were reconstructed by manual segmentation by four independent operators for both cases. CFD results were compared at nine axial locations along the SSS in terms of hydrodynamic and geometric parameters...
May 2016: Annals of Biomedical Engineering
Akbar Fakhri, Manish N Shah, Manu S Goyal
Type I Chiari malformations are congenital deformities involving cerebellar tonsillar herniation downward through the foramen magnum. Structurally, greater than 5 mm of tonsillar descent in adults and more than 6 mm in children is consistent with type I Chiari malformations. However, the radiographic severity of the tonsillar descent does not always correlate well with the clinical symptomatology. Advanced imaging can help clinically correlate imaging to symptoms. Specifically, cerebrospinal fluid (CSF) flow abnormalities are seen in patients with type I Chiari malformation...
October 2015: Neurosurgery Clinics of North America
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