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https://www.readbyqxmd.com/read/28741694/reduced-parahippocampal-volume-and-psychosis-symptoms-in-alzheimer-s-disease
#1
Emma McLachlan, Jennifer Bousfield, Robert Howard, Suzanne Reeves
OBJECTIVE: Establishing structural imaging correlates of psychosis symptoms in Alzheimer's disease (AD) could localise pathology and target symptomatic treatment. This study investigated whether psychosis symptoms are associated with visuoperceptual or frontal networks, and whether regional brain volume differences could be linked with the paranoid (persecutory delusions) or misidentification (misidentification phenomena and/or hallucinations) subtypes. METHODS: A total of 104 patients with probable AD (AddNeuroMed; 47 psychotic, 57 non-psychotic), followed up for at least one year with structural MRI at baseline...
July 25, 2017: International Journal of Geriatric Psychiatry
https://www.readbyqxmd.com/read/28730720/microstructural-white-matter-brain-abnormalities-in-patients-with-idiopathic-fecal-incontinence
#2
J Muthulingam, S Haas, T M Hansen, S Laurberg, L Lundby, H S Jørgensen, A M Drewes, K Krogh, J B Frøkjaer
BACKGROUND: Abnormal central nervous system processing of visceral sensation may be a part of the pathogenesis behind idiopathic fecal incontinence (IFI). Our aim was to characterize brain differences in patients with IFI and healthy controls by means of structural magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). METHODS: In 21 female patients with IFI and 15 female healthy controls, whole-brain structural differences in gray matter volume (GMV), cortical thickness, and white matter tracts fractional anisotropy (FA) were quantified...
July 21, 2017: Neurogastroenterology and Motility: the Official Journal of the European Gastrointestinal Motility Society
https://www.readbyqxmd.com/read/28723344/social-cognition-impairments-after-aneurysmal-subarachnoid-haemorrhage-associations-with-deficits-in-interpersonal-behaviour-apathy-and-impaired-self-awareness
#3
Anne M Buunk, Jacoba M Spikman, Wencke S Veenstra, Peter Jan van Laar, Jan D M Metzemaekers, J Marc C van Dijk, Linda C Meiners, Rob J M Groen
Behavioural disturbances are frequently found after aneurysmal subarachnoid haemorrhage (aSAH). Social cognition impairments have been suggested as a possible underlying mechanism for behavioural problems. Also, aSAH is likely to result in damage affecting frontal-subcortical circuits underlying social cognition. Therefore, we aimed to investigate social cognition after aSAH and its associations with behavioural problems (deficits in interpersonal behaviour, apathy, and impaired self-awareness) and focal as well as diffuse brain damage...
July 16, 2017: Neuropsychologia
https://www.readbyqxmd.com/read/28708033/neuropsychological-profile-and-social-cognition-in-congenital-central-hypoventilation-syndrome-cchs-correlation-with-neuroimaging-in-a-clinical-case
#4
Borja Esteso Orduña, Raquel Seijas Gómez, Elena García Esparza, Emily M Briceño, Javier Melero Llorente, María de la Concepción Fournier Del Castillo
INTRODUCTION: Congenital central hypoventilation syndrome (CCHS) is a rare genetic disorder due to paired-like homeobox gene (PHOX2B) mutations. CCHS patients suffer from dysregulation of the autonomic nervous system characterized by the absence of or extremely reduced response to hypercapnia and hypoxia, with neuropsychological deficits. The aim of this exploratory study is to describe the longitudinal neuropsychological profile and its correlations with magnetic resonance imaging (MRI) of a child with CCHS with a PHOX2B mutation...
July 14, 2017: Journal of Clinical and Experimental Neuropsychology
https://www.readbyqxmd.com/read/28670402/disc-rehydration-after-dynamic-stabilization-a-report-of-59-cases
#5
Atilla Yilmaz, Salim Senturk, Mehdi Sasani, Tunc Oktenoglu, Onur Yaman, Hakan Yildirim, Tuncer Suzer, Ali Fahir Ozer
STUDY DESIGN: A retrospective study investigating decrease in the nucleus pulposus signal intensity or disc height on magnetic resonance imaging (MRI) and disc degeneration. PURPOSE: Although a degenerated disc cannot self-regenerate, distraction or stabilization may provide suitable conditions for rehydration and possible regeneration. This study aimed to evaluate clinical outcomes and disc regeneration via MRI in a series of patients with degenerative disc disease (DDD) who underwent lumbar stabilization with a dynamic stabilization system (DSS)...
June 2017: Asian Spine Journal
https://www.readbyqxmd.com/read/28648465/planum-temporale-asymmetry-in-people-who-stutter
#6
Patricia M Gough, Emily L Connally, Peter Howell, David Ward, Jennifer Chesters, Kate E Watkins
PURPOSE: Previous studies have reported that the planum temporale - a language-related structure that normally shows a leftward asymmetry - had reduced asymmetry in people who stutter (PWS) and reversed asymmetry in those with severe stuttering. These findings are consistent with the theory that altered language lateralization may be a cause or consequence of stuttering. Here, we re-examined these findings in a larger sample of PWS. METHODS: We evaluated planum temporale asymmetry in structural MRI scans obtained from 67 PWS and 63 age-matched controls using: 1) manual measurements of the surface area; 2) voxel-based morphometry to automatically calculate grey matter density...
June 16, 2017: Journal of Fluency Disorders
https://www.readbyqxmd.com/read/28630885/bayesian-framework-inspired-no-reference-region-of-interest-quality-measure-for-brain-mri-images
#7
Michael Osadebey, Marius Pedersen, Douglas Arnold, Katrina Wendel-Mitoraj
We describe a postacquisition, attribute-based quality assessment method for brain magnetic resonance imaging (MRI) images. It is based on the application of Bayes theory to the relationship between entropy and image quality attributes. The entropy feature image of a slice is segmented into low- and high-entropy regions. For each entropy region, there are three separate observations of contrast, standard deviation, and sharpness quality attributes. A quality index for a quality attribute is the posterior probability of an entropy region given any corresponding region in a feature image where quality attribute is observed...
April 2017: Journal of Medical Imaging
https://www.readbyqxmd.com/read/28630340/enhancing-t1-magnetic-resonance-imaging-contrast-with-internalized-gadolinium-iii-in-a-multilayer-nanoparticle
#8
Valeria S Marangoni, Oara Neumann, Luke Henderson, Caterina C Kaffes, Hui Zhang, Runmin Zhang, Sandra Bishnoi, Ciceron Ayala-Orozco, Valtencir Zucolotto, James A Bankson, Peter Nordlander, Naomi J Halas
Multifunctional nanoparticles for biomedical applications have shown extraordinary potential as contrast agents in various bioimaging modalities, near-IR photothermal therapy, and for light-triggered therapeutic release processes. Over the past several years, numerous studies have been performed to synthesize and enhance MRI contrast with nanoparticles. However, understanding the MRI enhancement mechanism in a multishell nanoparticle geometry, and controlling its properties, remains a challenge. To systematically examine MRI enhancement in a nanoparticle geometry, we have synthesized MRI-active Au nanomatryoshkas...
July 3, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28620215/theta-band-transcranial-alternating-current-stimulations-modulates-network-behavior-of-dorsal-anterior-cingulate-cortex
#9
Keiichi Onoda, Toshikazu Kawagoe, Haixia Zheng, Shuhei Yamaguchi
Dorsal anterior cingulate cortex (dACC) is an important region in the processing of both cognition and affect. Recently, transcranial brain stimulation has been used to modulate cortical activity, but it is unclear whether this stimulation has a specific effect on dACC. Based on EEG evidence that frontal midline theta activity is generated in dACC, we hypothesized that transcranial alternating current stimulation (tACS) with theta band frequency would modulate neural networks including dACC. In this study, we examined the effects of theta band tACS on functional networks and emotional state...
June 15, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28619436/tumefactive-demyelinating-lesions-a-comprehensive-review
#10
REVIEW
Hussein Algahtani, Bader Shirah, Ali Alassiri
Tumefactive multiple sclerosis or tumefactive demyelinating lesion (TDL) is one of the rare variants of multiple sclerosis (MS) posing a diagnostic challenge and a therapeutic enigma since it is difficult to distinguish from a true central nervous system (CNS) neoplasm or other CNS lesions on magnetic resonance imaging (MRI). The prevalence of TDL is estimated to be 1-3/1000 cases of MS with an annual incidence of 0.3/100,000. This could be an underestimate due to unavailability of a global MS registry and under-reporting of this condition...
May 2017: Multiple Sclerosis and related Disorders
https://www.readbyqxmd.com/read/28617222/an-extensive-assessment-of-network-alignment-algorithms-for-comparison-of-brain-connectomes
#11
Marianna Milano, Pietro Hiram Guzzi, Olga Tymofieva, Duan Xu, Christofer Hess, Pierangelo Veltri, Mario Cannataro
BACKGROUND: Recently the study of the complex system of connections in neural systems, i.e. the connectome, has gained a central role in neurosciences. The modeling and analysis of connectomes are therefore a growing area. Here we focus on the representation of connectomes by using graph theory formalisms. Macroscopic human brain connectomes are usually derived from neuroimages; the analyzed brains are co-registered in the image domain and brought to a common anatomical space. An atlas is then applied in order to define anatomically meaningful regions that will serve as the nodes of the network - this process is referred to as parcellation...
June 6, 2017: BMC Bioinformatics
https://www.readbyqxmd.com/read/28584970/morphometric-evaluation-of-facial-and-vestibulocochlear-nerves-using-magnetic-resonance-imaging-comparison-of-meni%C3%A3-re-s-disease-ears-with-normal-hearing-ears
#12
Annika Henneberger, Birgit Ertl-Wagner, Maximilian Reiser, Robert Gürkov, Wilhelm Flatz
Loss of neural structures (such as hair cells or neurones within the spiral ganglion) has been proposed to be involved in Menière's disease (MD) (Spoendlin et al. Acta oto-laryngologica Supplementum 499:1-21, 1; Merchant et al. Eur Arch Oto-Rhino-Laryngol Off J Eur Feder Oto-Rhino-Laryngol Soc (EUFOS) Affil German Soc Oto-Rhino-Laryngol Head Neck Surg 252(2):63-75, 2; Tsuji et al. Ann Otol Rhinol Laryngol Suppl 81:26-31, 3; Kariya, Otol Neurotol Off Publ Am Otol Soc Am Neurotol Soc Eur Acad Otol Neurotol 28(8):1063-1068, 4; Megerian Laryngoscope 115(9):1525-1535, 5) but this has yet to be confirmed...
August 2017: European Archives of Oto-rhino-laryngology
https://www.readbyqxmd.com/read/28573962/anatomical-integration-and-rich-club-connectivity-in-euthymic-bipolar-disorder
#13
S O'Donoghue, L Kilmartin, D O'Hora, L Emsell, C Langan, S McInerney, N J Forde, A Leemans, B Jeurissen, G J Barker, P McCarthy, D M Cannon, C McDonald
BACKGROUND: Although repeatedly associated with white matter microstructural alterations, bipolar disorder (BD) has been relatively unexplored using complex network analysis. This method combines structural and diffusion magnetic resonance imaging (MRI) to model the brain as a network and evaluate its topological properties. A group of highly interconnected high-density structures, termed the 'rich-club', represents an important network for integration of brain functioning. This study aimed to assess structural and rich-club connectivity properties in BD through graph theory analyses...
July 2017: Psychological Medicine
https://www.readbyqxmd.com/read/28558274/active-control-of-the-spatial-mri-phase-distribution-with-optimal-control-theory
#14
Pauline M Lefebvre, Eric Van Reeth, Hélène Ratiney, Olivier Beuf, Elisabeth Brusseau, Simon A Lambert, Steffen J Glaser, Dominique Sugny, Denis Grenier, Kevin Tse Ve Koon
This paper investigates the use of Optimal Control (OC) theory to design Radio-Frequency (RF) pulses that actively control the spatial distribution of the MRI magnetization phase. The RF pulses are generated through the application of the Pontryagin Maximum Principle and optimized so that the resulting transverse magnetization reproduces various non-trivial and spatial phase patterns. Two different phase patterns are defined and the resulting optimal pulses are tested both numerically with the ODIN MRI simulator and experimentally with an agar gel phantom on a 4...
May 22, 2017: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/28549795/brain-grey-and-white-matter-predictors-of-verbal-ability-traits-in-older-age-the-lothian-birth-cohort-1936
#15
Paul Hoffman, Simon R Cox, Dominika Dykiert, Susana Muñoz Maniega, Maria C Valdés Hernández, Mark E Bastin, Joanna M Wardlaw, Ian J Deary
Cerebral grey and white matter MRI parameters are related to general intelligence and some specific cognitive abilities. Less is known about how structural brain measures relate specifically to verbal processing abilities. We used multi-modal structural MRI to investigate the grey matter (GM) and white matter (WM) correlates of verbal ability in 556 healthy older adults (mean age = 72.68 years, s.d. = .72 years). Structural equation modelling was used to decompose verbal performance into two latent factors: a storage factor that indexed participants' ability to store representations of verbal knowledge and an executive factor that measured their ability to regulate their access to this information in a flexible and task-appropriate manner...
May 24, 2017: NeuroImage
https://www.readbyqxmd.com/read/28536804/modeling-dynamic-contrast-enhanced-mri-data-with-a-constrained-local-aif
#16
Chong Duan, Jesper F Kallehauge, Carlos J Pérez-Torres, G Larry Bretthorst, Scott C Beeman, Kari Tanderup, Joseph J H Ackerman, Joel R Garbow
PURPOSE: This study aims to develop a constrained local arterial input function (cL-AIF) to improve quantitative analysis of dynamic contrast-enhanced (DCE)-magnetic resonance imaging (MRI) data by accounting for the contrast-agent bolus amplitude error in the voxel-specific AIF. PROCEDURES: Bayesian probability theory-based parameter estimation and model selection were used to compare tracer kinetic modeling employing either the measured remote-AIF (R-AIF, i.e...
May 23, 2017: Molecular Imaging and Biology: MIB: the Official Publication of the Academy of Molecular Imaging
https://www.readbyqxmd.com/read/28527756/radiological-lumbar-stenosis-severity-predicts-worsening-sagittal-malalignment-on-full-body-standing-stereoradiographs
#17
Aaron J Buckland, Subaraman Ramchandran, Louis Day, Shay Bess, Themistocles Protopsaltis, Peter G Passias, Bassel G Diebo, Renaud Lafage, Virginie Lafage, Akhila Sure, Thomas J Errico
BACKGROUND CONTEXT: Patients with degenerative lumbar stenosis (DLS) adopt a forward flexed posture in an attempt to decompress neural elements. The relationship between sagittal alignment and severity of lumbar stenosis has not previously been studied. PURPOSE: We hypothesized that patients with increasing radiological severity of lumbar stenosis will exhibit worsening sagittal alignment. STUDY DESIGN: This is a cross-sectional study. PATIENT SAMPLE: Our sample consists of patients who have DLS...
May 17, 2017: Spine Journal: Official Journal of the North American Spine Society
https://www.readbyqxmd.com/read/28515708/disrupted-structural-and-functional-networks-and-their-correlation-with-alertness-in-right-temporal-lobe-epilepsy-a-graph-theory-study
#18
Wenyu Jiang, Jianping Li, Xuemei Chen, Wei Ye, Jinou Zheng
Previous studies have shown that temporal lobe epilepsy (TLE) involves abnormal structural or functional connectivity in specific brain areas. However, limited comprehensive studies have been conducted on TLE associated changes in the topological organization of structural and functional networks. Additionally, epilepsy is associated with impairment in alertness, a fundamental component of attention. In this study, structural networks were constructed using diffusion tensor imaging tractography, and functional networks were obtained from resting-state functional MRI temporal series correlations in 20 right temporal lobe epilepsy (rTLE) patients and 19 healthy controls...
2017: Frontiers in Neurology
https://www.readbyqxmd.com/read/28499604/iron-oxide-nanoparticles-in-vivo-in-vitro-biomedical-applications-and-in-silico-studies
#19
REVIEW
Miroslava Nedyalkova, Borjana Donkova, Julia Romanova, George Tzvetkov, Sergio Madurga, Vasil Simeonov
The review presents a broad overview of the biomedical applications of surface functionalized iron oxide nanoparticles (IONPs) as magnetic resonance imaging (MRI) agents for sensitive and precise diagnosis tool and synergistic combination with other imaging modalities. Then, the recent progress in therapeutic applications, such as hyperthermia is discussed and the available toxicity data of magnetic nanoparticles concerning in vitro and in vivo biomedical applications are addressed. This review also presents the available computer models using molecular dynamics (MD), Monte Carlo (MC) and density functional theory (DFT), as a basis for a complete understanding of the behaviour and morphology of functionalized IONPs, for improving NPs surface design and expanding the potential applications in nanomedicine...
May 3, 2017: Advances in Colloid and Interface Science
https://www.readbyqxmd.com/read/28486817/altered-network-topology-in-patients-with-primary-brain-tumors-after-fractionated-radiotherapy
#20
Naeim Bahrami, Tyler M Seibert, Roshan Karunamuni, Hauke Bartsch, AnithaPriya Krishnan, Nikdokht Farid, Jona A Hattangadi-Gluth, Carrie R McDonald
Radiation therapy (RT) is a critical treatment modality for patients with brain tumors, although it can cause adverse effects. Recent data suggest that brain RT is associated with dose-dependent cortical atrophy, which could disrupt neocortical networks. This study examines whether brain RT affects structural network properties in brain tumor patients. We applied graph theory to MRI-derived cortical thickness estimates of 54 brain tumor patients before and after RT. Cortical surfaces were parcellated into 68 regions and correlation matrices were created for patients pre- and post-RT...
June 2017: Brain Connectivity
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