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https://www.readbyqxmd.com/read/29786833/assessment-of-cerebral-perfusion-and-edema-in-preeclampsia-with-intravoxel-incoherent-motion-mri
#1
Maria Nelander, Daniel Hannsberger, Inger Sundström-Poromaa, Lina Bergman, Jan Weis, Helena Åkerud, Johan Wikström, Anna-Karin Wikström
INTRODUCTION: Cerebral complications are the main reasons for morbidity and mortality in preeclampsia and eclampsia. Still we do not know if the pathophysiology entails hypo- or hyperperfusion of the brain, or how and when edema emerges, due to the difficulty to examine the cerebral circulation. MATERIAL AND METHODS: We have used a non-invasive diffusion weighted magnetic resonance imaging (MRI) technique, intravoxel incoherent motion, to study cerebral perfusion on the capillary level and cerebral edema in women with preeclampsia (n=30), normal pregnancy (n=32) and non-pregnant women (n=16)...
May 22, 2018: Acta Obstetricia et Gynecologica Scandinavica
https://www.readbyqxmd.com/read/29785933/a-comparison-of-peripheral-imaging-technologies-for-bone-and-muscle-quantification-a-review-of-segmentation-techniques
#2
REVIEW
Andy Kin On Wong, Sarah Lynn Manske
Musculoskeletal science has developed many overlapping branches, necessitating specialists from 1 area of focus to often require the expertise in others. In terms of imaging, this means obtaining a comprehensive illustration of bone, muscle, and fat tissues. There is currently a lack of a reliable resource for end users to learn about these tissues' imaging and quantification techniques together. An improved understanding of these tissues has been an important progression toward better prediction of disease outcomes and better elucidation of their interaction with frailty, aging, and metabolic disorders...
April 17, 2018: Journal of Clinical Densitometry
https://www.readbyqxmd.com/read/29785932/cortical-thickness-correlates-of-minor-neurological-signs-in-patients-with-first-episode-psychosis
#3
Simone Ciufolini, Maria Francesca Ponteduro, Tiago Reis-Marques, Heather Taylor, Valeria Mondelli, Carmine M Pariante, Stefania Bonaccorso, Raymond Chan, Andy Simmons, Anthony David, Marta Di Forti, Robin M Murray, Paola Dazzan
Neurological soft signs (NSS) are subtle abnormalities of motor and sensory function that are present in the absence of localized brain pathological lesions. In psychoses they have been consistently associated with a distinct pattern of cortical and subcortical brain structural alterations at the level of the heteromodal cortex and basal ganglia. However, a more specific and accurate evaluation of the cytoarchitecture of the cortical mantle could further advance our understanding of the neurobiological substrate of psychosis...
May 18, 2018: Schizophrenia Research
https://www.readbyqxmd.com/read/29785155/the-volume-of-the-cerebellum-in-the-second-semester-of-gestation
#4
Damiana Vulturar, Alexandru Fărcăşanu, Flaviu Turcu, Dan Boitor, Carmen Crivii
Background and aims: The cerebellum ("little brain"), the largest part of hind brain, lies in the posterior cranial fossa, beneath the occipital lobe and dorsal to the brainstem. It develops over a long period: it is one of the first structures in the brain to begin to differentiate, but one of the last to mature. The use of ultrasonography has significantly improved the evaluation of fetal growth and development and has permitted prenatal diagnosis of a variety of congenital malformations...
2018: Clujul Medical (1957)
https://www.readbyqxmd.com/read/29784430/microvascular-decompression-for-hemifacial-spasm-surgical-techniques-and-intraoperative-monitoring
#5
M Sindou, P Mercier
Primary hemifacial spasm with few exceptions is due to the vascular compression of the facial nerve that can be evidenced with high resolution MRI. Microvascular decompression is the only curative treatment for this pathology. According to literature review detailed in chapter "conflicting vessels", the compression is located at the facial Root Exit Zone (REZ) in 95% of the cases, and in 5% distally at the cisternal or the intrameatal portion of the root as the sole conflict or in addition to one at brainstem/REZ...
May 18, 2018: Neuro-Chirurgie
https://www.readbyqxmd.com/read/29784248/conventional-and-advanced-mri-in-multiple-sclerosis
#6
REVIEW
C Louapre
Magnetic resonance imaging (MRI) plays a central role in the management of patients with multiple sclerosis (MS). T2-weighted/FLAIR lesions have been included in the diagnostic criteria since 2001, and the importance of the technology has been expanded in each successive revision of the McDonald criteria. While the typical focal hyperintense lesions seen on T2 and FLAIR sequences in several areas of the central nervous system are key features for MS diagnosis, they can also be used to monitor disease activity, particularly in asymptomatic patients, and to evaluate therapeutic responses...
May 18, 2018: Revue Neurologique
https://www.readbyqxmd.com/read/29782993/generalized-recurrent-neural-network-accommodating-dynamic-causal-modeling-for-functional-mri-analysis
#7
Yuan Wang, Yao Wang, Yvonne W Lui
Dynamic Causal Modeling (DCM) is an advanced biophysical model which explicitly describes the entire process from experimental stimuli to functional magnetic resonance imaging (fMRI) signals via neural activity and cerebral hemodynamics. To conduct a DCM study, one needs to represent the experimental stimuli as a compact vector-valued function of time, which is hard in complex tasks such as book reading and natural movie watching. Deep learning provides the state-of-the-art signal representation solution, encoding complex signals into compact dense vectors while preserving the essence of the original signals...
May 18, 2018: NeuroImage
https://www.readbyqxmd.com/read/29782369/neuroimaging-in-epilepsy
#8
Meneka Kaur Sidhu, John S Duncan, Josemir W Sander
PURPOSE OF REVIEW: Epilepsy neuroimaging is important for detecting the seizure onset zone, predicting and preventing deficits from surgery and illuminating mechanisms of epileptogenesis. An aspiration is to integrate imaging and genetic biomarkers to enable personalized epilepsy treatments. RECENT FINDINGS: The ability to detect lesions, particularly focal cortical dysplasia and hippocampal sclerosis, is increased using ultra high-field imaging and postprocessing techniques such as automated volumetry, T2 relaxometry, voxel-based morphometry and surface-based techniques...
May 17, 2018: Current Opinion in Neurology
https://www.readbyqxmd.com/read/29782314/a-retrospective-belgian-multi-center-mri-biomarker-study-in-alzheimer-s-disease-remember
#9
Ellis Niemantsverdriet, Annemie Ribbens, Christine Bastin, Florence Benoit, Bruno Bergmans, Jean-Christophe Bier, Roxanne Bladt, Lene Claes, Peter Paul De Deyn, Olivier Deryck, Bernard Hanseeuw, Adrian Ivanoiu, Jean-Claude Lemper, Eric Mormont, Gaëtane Picard, Eric Salmon, Kurt Segers, Anne Sieben, Dirk Smeets, Hanne Struyfs, Evert Thiery, Jos Tournoy, Eric Triau, Anne-Marie Vanbinst, Jan Versijpt, Maria Bjerke, Sebastiaan Engelborghs
BACKGROUND: Magnetic resonance imaging (MRI) acquisition/processing techniques assess brain volumes to explore neurodegeneration in Alzheimer's disease (AD). OBJECTIVE: We examined the clinical utility of MSmetrix and investigated if automated MRI volumes could discriminate between groups covering the AD continuum and could be used as a predictor for clinical progression. METHODS: The Belgian Dementia Council initiated a retrospective, multi-center study and analyzed whole brain (WB), grey matter (GM), white matter (WM), cerebrospinal fluid (CSF), cortical GM (CGM) volumes, and WM hyperintensities (WMH) using MSmetrix in the AD continuum...
May 16, 2018: Journal of Alzheimer's Disease: JAD
https://www.readbyqxmd.com/read/29780855/magnetic-resonance-imaging-and-histopathological-visualization-of-human-dural-lymphatic-vessels
#10
Seung-Kwon Ha, Govind Nair, Martina Absinta, Nicholas J Luciano, Daniel S Reich
In this protocol, we describe a method to visualize and map dural lymphatic vessels in-vivo using magnetic resonance imaging (MRI) and ex-vivo using histopathological techniques. While MRI protocols for routine imaging of meningeal lymphatics include contrast-enhanced T2-FLAIR and T1- weighted black-blood imaging, a more specific 3D mapping of the lymphatic system can be obtained by administering two distinct gadolinium-based MRI contrast agents on different days (gadofosveset and gadobutrol) and subsequently processing images acquired before and after administration of each type of contrast...
April 20, 2018: Bio-protocol
https://www.readbyqxmd.com/read/29780498/direct-and-indirect-hyperpolarisation-of-amines-using-para-hydrogen
#11
Wissam Iali, Peter J Rayner, Adel Alshehri, A Jonathan Holmes, Amy J Ruddlesden, Simon B Duckett
Nuclear Magnetic Resonance (NMR) and Magnetic Resonance Imaging (MRI) are two widely used techniques for the study of molecules and materials. Hyperpolarisation methods, such as Signal Amplification By Reversible Exchange (SABRE), turn typically weak magnetic resonance responses into strong signals. In this article we detail how it is possible to hyperpolarise the 1 H, 13 C and 15 N nuclei of a range of amines. This involved showing how primary amines form stable but labile complexes of the type [Ir(H)2 (IMes)(amine)3 ]Cl that allow para hydrogen to relay its latent polarisation into the amine...
April 21, 2018: Chemical Science
https://www.readbyqxmd.com/read/29780447/fluorinated-eu-ii-based-multimodal-contrast-agent-for-temperature-and-redox-responsive-magnetic-resonance-imaging
#12
Lina A Basal, Matthew D Bailey, Jonathan Romero, Meser M Ali, Lyazat Kurenbekova, Jason Yustein, Robia G Pautler, Matthew J Allen
Magnetic resonance imaging (MRI) using redox-active, EuII -containing complexes is one of the most promising techniques for noninvasively imaging hypoxia in vivo . In this technique, positive ( T 1 -weighted) contrast enhancement persists in areas of relatively low oxidizing ability, such as hypoxic tissue. Herein, we describe a fluorinated, EuII -containing complex in which the redox-active metal is caged by intramolecular interactions. The position of the fluorine atoms enables temperature-responsive contrast enhancement in the reduced form of the contrast agent and detection of the oxidized contrast agent via MRI in vivo ...
December 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/29780302/unified-bayesian-estimator-of-eeg-reference-at-infinity-rrest-regularized-reference-electrode-standardization-technique
#13
Shiang Hu, Dezhong Yao, Pedro A Valdes-Sosa
The choice of reference for the electroencephalogram (EEG) is a long-lasting unsolved issue resulting in inconsistent usages and endless debates. Currently, both the average reference (AR) and the reference electrode standardization technique (REST) are two primary, apparently irreconcilable contenders. We propose a theoretical framework to resolve this reference issue by formulating both (a) estimation of potentials at infinity, and (b) determination of the reference, as a unified Bayesian linear inverse problem, which can be solved by maximum a posterior estimation...
2018: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/29780223/surgical-outcomes-and-predictors-of-complication-in-elderly-patients-with-meningiomas
#14
Ayman E Galhom, A A Madawi, M M Ellabban
Background: Surgical management of symptomatic meningioma in elderly is still a high-risk surgery due to increased incidence of complication rate. Many scoring systems have been proposed to expect the surgical risk and the outcome.The study tries to assess cranial meningioma surgery in elderly using the Ibañez grade for complication rate and the Geriatric Scoring System (GSS) for the surgical outcome (GSS). Methods: A clinical and radiological data were studied retrospectively in 42 patients with a primary intracranial meningioma at or above the age of 65...
2018: The Egyptian journal of neurology, psychiatry and neurosurgery
https://www.readbyqxmd.com/read/29778509/longitudinal-observations-using-simultaneous-fmri-multiple-channel-electrophysiology-recording-and-chemical-microiontophoresis-in-the-rat-brain
#15
Saul Jaime, Jose E Cavazos, Yihong Yang, Hanbing Lu
BACKGROUND: fMRI blood oxygenation level-dependent (BOLD) signal has been widely used as a surrogate for neural activity. However, interpreting differences in BOLD fMRI based on underlying neuronal activity remains a challenge. Concurrent rsMRI data collection and electrophysiological recording in combination with microiontophoretically injected modulatory chemicals allows for improved understanding of the relationship between resting state BOLD and neuronal activity. NEW METHODS: Simultaneous fMRI, multi-channel intracortical electrophysiology and focal pharmacological manipulation data to be acquired longitudinally in rats for up to 2 months...
May 17, 2018: Journal of Neuroscience Methods
https://www.readbyqxmd.com/read/29777892/surgically-treated-de-novo-cervico-medullary-arachnoid-cyst-in-a-symptomatic-adult-patient
#16
William Clifton, Gazanfar Rahmathulla, Kourosh Tavanaiepour, Dunbar Alcindor, George Jakubek, Daryoush Tavanaiepour
Arachnoid cysts are a relatively common finding in adult patients, especially with the advent of advanced imaging techniques. The overall incidence ranges from 1-2%, and the majority are clinically silent1,2 . Arachnoid cysts are postulated to arise by congenital anomalies or trauma1 . De novo formation of arachnoid cysts has been reported, but is exceptionally rare and mostly found in the pediatric population after head trauma3-5 . There have only been two reported cases of symptomatic de novo arachnoid cyst formation in adult patients to date, both with histories of head trauma6,7 ...
May 16, 2018: World Neurosurgery
https://www.readbyqxmd.com/read/29777828/mutual-connectivity-analysis-of-resting-state-functional-mri-data-with-local-models
#17
Adora M DSouza, Anas Z Abidin, Udaysankar Chockanathan, Giovanni Schifitto, Axel Wismüller
Functional connectivity analysis of functional MRI (fMRI) can represent brain networks and reveal insights into interactions amongst different brain regions. However, most connectivity analysis approaches adopted in practice are linear and non-directional. In this paper, we demonstrate the advantage of a data-driven, directed connectivity analysis approach called Mutual Connectivity Analysis using Local Models (MCA-LM) that approximates connectivity by modeling nonlinear dependencies of signal interaction, over more conventionally used approaches, such as Pearson's and partial correlation, Patel's conditional dependence measures, etcetera...
May 16, 2018: NeuroImage
https://www.readbyqxmd.com/read/29777822/effects-of-global-signal-regression-and-subtraction-methods-on-resting-state-functional-connectivity-using-arterial-spin-labeling-data
#18
João Paulo Santos Silva, Luciana da Mata Mônaco, André Monteiro Paschoal, Ícaro Agenor Ferreira de Oliveira, Renata Ferranti Leoni
BACKGROUND: Arterial spin labeling (ASL) is an established magnetic resonance imaging (MRI) technique that is finding broader applications in functional studies of the healthy and diseased brain. To promote improvement in cerebral blood flow (CBF) signal specificity, many algorithms and imaging procedures, such as subtraction methods, were proposed to eliminate or, at least, minimize noise sources. Therefore, this study addressed the main considerations of how CBF functional connectivity (FC) is changed, regarding resting brain network (RBN) identification and correlations between regions of interest (ROI), by different subtraction methods and removal of residual motion artifacts and global signal fluctuations (RMAGSF)...
May 16, 2018: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/29777821/regional-cardiac-function-analysis-from-tagged-mri-images-comparison-of-techniques-harmonic-phase-harp-versus-sinusoidal-modeling-sinmod-analysis
#19
El-Sayed H Ibrahim, Jadranka Stojanovska, Azza Hassanein, Claire Duvernoy, Pierre Croisille, Rodica Pop-Busui, Scott D Swanson
Cardiac MRI tagging is a valuable technique for evaluating regional heart function. Currently, there are a number of different techniques for analyzing the tagged images. Specifically, k-space-based analysis techniques showed to be much faster than image-based techniques, where harmonic-phase (HARP) and sine-wave modeling (SinMod) stand as two famous techniques of the former group, which are frequently used in clinical studies. In this study, we compared HARP and SinMod and studied inter-observer variability between the two techniques for evaluating myocardial strain and apical-to-base torsion in numerical phantom, nine healthy controls, and thirty diabetic patients...
May 16, 2018: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/29777820/accuracy-and-precision-of-quantitative-dce-mri-parameters-how-should-one-estimate-contrast-concentration
#20
Nicole Wake, Hersh Chandarana, Henry Rusinek, Koji Fujimoto, Linda Moy, Daniel K Sodickson, Sungheon Gene Kim
INTRODUCTION: Pharmacokinetic parameters derived from dynamic contrast-enhanced MRI (DCE-MRI) data are sensitive to acquisition and post-processing techniques, which makes it difficult to compare results obtained using different methods. In particular, one of the most important factors affecting estimation of model parameters is how to convert MRI signal intensities to contrast agent concentration. The purpose of our study was to quantitatively compare a linear signal-to-concentration conversion (LC) as an approximation and a non-linear conversion (NLC) based on the MRI signal equation, in terms of the accuracy and precision of the pharmacokinetic parameters in T1 -weighted DCE-MRI...
May 16, 2018: Magnetic Resonance Imaging
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