557,837 results match your criteria human mri

Altered sensorimotor integration in multiple sclerosis: A combined neurophysiological and functional MRI study.

Clin Neurophysiol 2021 Jun 25;132(9):2191-2198. Epub 2021 Jun 25.

IRCCS Neuromed, Pozzilli, IS, Italy; Department of Human Neurosciences, Sapienza University of Rome, Rome, Italy.

Objective: To explore whether abnormal thalamic resting-state functional connectivity (rsFC) contributes to altered sensorimotor integration and hand dexterity impairment in multiple sclerosis (MS).

Methods: To evaluate sensorimotor integration, we recorded kinematic features of index finger abductions during somatosensory temporal discrimination threshold (STDT) testing in 36 patients with relapsing-remitting MS and 39 healthy controls (HC). Participants underwent a multimodal 3T structural and functional MRI protocol. Read More

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Impact of anesthesia on static and dynamic functional connectivity in mice.

Neuroimage 2021 Jul 20;241:118413. Epub 2021 Jul 20.

Jikei University School of Medicine, 3-25-8 Nishishinbashi, Minato City, Tokyo 105-8461, Japan; Riken, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.

A few studies have compared the static functional connectivity between awake and lightly anesthetized states in rodents by resting-state fMRI. However, impact of light anesthesia on static and dynamic fluctuations in functional connectivity has not been fully understood. Here, we developed a resting-state fMRI protocol to perform awake and anesthetized functional MRI in the same mice. Read More

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A Pilot Behavioural and Neuroimaging Investigation on Photothrombotic Stroke Models in Rhesus Monkeys.

J Neurosci Methods 2021 Jul 19:109291. Epub 2021 Jul 19.

National Resource Center for Non-Human Primates, Kunming Primate Research Center, and National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China. Electronic address:

Background: Ischemic stroke leads to a long-term disability in humans and no efficient clinical therapy exists to date. The middle cerebral artery occlusion (MCAO) model in non-human primates has shown to be of value for translational stroke research. New method In the current study, a photothrombotic (PT) stroke model was established in rhesus monkeys with either a proximal or distal segment of middle cerebral artery (MCA) thrombosis. Read More

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Age-Dependent Changes in Total and Free Water Content of In Vivo Human Lenses Measured by Magnetic Resonance Imaging.

Invest Ophthalmol Vis Sci 2021 Jul;62(9):33

Department of Physiology, School of Medical Sciences, New Zealand National Eye Centre, University of Auckland, New Zealand.

Purpose: To use magnetic resonance imaging (MRI) to measure age-dependent changes in total and free water in human lenses in vivo.

Methods: Sixty-four healthy adults aged 18 to 86 years were recruited, fitted with a 32-channel head receiver coil, and placed in a 3 Tesla clinical MR scanner. Scans of the crystalline lens were obtained using a volumetric interpolated breath-hold examination sequence with dual flip angles, which were corrected for field inhomogeneity post-acquisition using a B1-map obtained using a turbo-FLASH sequence. Read More

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Magnetic-resonance-based measurement of electromagnetic fields and conductivity in vivo using single current administration-A machine learning approach.

PLoS One 2021 22;16(7):e0254690. Epub 2021 Jul 22.

School of Biological Health System Engineering, Arizona State University, Tempe, Arizona, United States of America.

Diffusion tensor magnetic resonance electrical impedance tomography (DT-MREIT) is a newly developed technique that combines MR-based measurements of magnetic flux density with diffusion tensor MRI (DT-MRI) data to reconstruct electrical conductivity tensor distributions. DT-MREIT techniques normally require injection of two independent current patterns for unique reconstruction of conductivity characteristics. In this paper, we demonstrate an algorithm that can be used to reconstruct the position dependent scale factor relating conductivity and diffusion tensors, using flux density data measured from only one current injection. Read More

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Volume of the right supramarginal gyrus is associated with a maintenance of emotion recognition ability.

PLoS One 2021 22;16(7):e0254623. Epub 2021 Jul 22.

Department of Physiology, Showa University School of Medicine, Tokyo, Japan.

Emotion recognition is known to change with age, but associations between the change and brain atrophy are not well understood. In the current study atrophied brain regions associated with emotion recognition were investigated in elderly and younger participants. Group comparison showed no difference in emotion recognition score, while the score was associated with years of education, not age. Read More

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Relationships between early maternal warmth and social connection: A randomized clinical trial with naltrexone.

Psychosom Med 2021 Jul 21. Epub 2021 Jul 21.

University of Pittsburgh, Department of Psychology, Pittsburgh, PA, USA. University of Pittsburgh School of Medicine, Department of Psychiatry, Pittsburgh, PA, USA. San Diego State University, Department of Psychology, San Diego, CA, USA.

Objective: Early experiences of having received maternal warmth predict responses to opportunities to connect with others later in life. However, understanding of neurochemical mechanisms by which such relationships emerge remain incomplete. Endogenous opioids, involved in social connection in both animals and humans, may contribute to this link. Read More

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Amount of Hearing Aid Use Impacts Neural Oscillatory Dynamics Underlying Verbal Working Memory Processing for Children With Hearing Loss.

Ear Hear 2021 Jul 20. Epub 2021 Jul 20.

Institute for Human Neuroscience, Boys Town National Research Hospital (BTNRH), Omaha, Nebraska, USA Center for Magnetoencephalography (MEG), University of Nebraska Medical Center (UNMC), Omaha, Nebraska, USA Wendell Johnson Speech and Hearing Center, Department of Communication Sciences and Disorders, University of Iowa, Iowa City, Iowa, USA Audibility, Perception, and Cognition Laboratory, BTNRH, Omaha, Nebraska, USA.

Objectives: Children with hearing loss (CHL) may exhibit spoken language delays and may also experience deficits in other cognitive domains including working memory. Consistent hearing aid use (i.e. Read More

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Optimizing Visual Cortex Parameterization with Error-Tolerant Teichmüller Map in Retinotopic Mapping.

Med Image Comput Comput Assist Interv 2020 29;12267:218-227. Epub 2020 Sep 29.

Arizona State University, Tempe AZ 85201, USA.

The mapping between the visual input on the retina to the cortical surface, i.e., retinotopic mapping, is an important topic in vision science and neuroscience. Read More

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September 2020

The Influence of Radio-Frequency Transmit Field Inhomogeneities on the Accuracy of G-ratio Weighted Imaging.

Front Neurosci 2021 5;15:674719. Epub 2021 Jul 5.

Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.

G-ratio weighted imaging is a non-invasive, MRI-based technique that aims at estimating an aggregated measure of relative myelination of axons across the entire brain white matter. The MR g-ratio and its constituents (axonal and myelin volume fraction) are more specific to the tissue microstructure than conventional MRI metrics targeting either the myelin or axonal compartment. To calculate the MR g-ratio, an MRI-based myelin-mapping technique is combined with an axon-sensitive MR technique (such as diffusion MRI). Read More

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Sexually dimorphic neuroanatomical differences relate to ASD-relevant behavioral outcomes in a maternal autoantibody mouse model.

Mol Psychiatry 2021 Jul 21. Epub 2021 Jul 21.

Department of Internal Medicine, Division of Rheumatology, Allergy, and Clinical Immunology, University of California, Davis, CA, USA.

Immunoglobulin G (IgG) autoantibodies reactive to fetal brain proteins in mothers of children with ASD have been described by several groups. To understand their pathologic significance, we developed a mouse model of maternal autoantibody related ASD (MAR-ASD) utilizing the peptide epitopes from human autoantibody reactivity patterns. Male and female offspring prenatally exposed to the salient maternal autoantibodies displayed robust deficits in social interactions and increased repetitive self-grooming behaviors as juveniles and adults. Read More

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Global waves synchronize the brain's functional systems with fluctuating arousal.

Sci Adv 2021 Jul 21;7(30). Epub 2021 Jul 21.

Department of Radiology, Washington University, St. Louis, MO 63110, USA.

We propose and empirically support a parsimonious account of intrinsic, brain-wide spatiotemporal organization arising from traveling waves linked to arousal. We hypothesize that these waves are the predominant physiological process reflected in spontaneous functional magnetic resonance imaging (fMRI) signal fluctuations. The correlation structure ("functional connectivity") of these fluctuations recapitulates the large-scale functional organization of the brain. Read More

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Downstream effects of polypathology on neurodegeneration of medial temporal lobe subregions.

Acta Neuropathol Commun 2021 Jul 21;9(1):128. Epub 2021 Jul 21.

Department of Radiology, University of Pennsylvania, Philadelphia, USA.

The medial temporal lobe (MTL) is a nidus for neurodegenerative pathologies and therefore an important region in which to study polypathology. We investigated associations between neurodegenerative pathologies and the thickness of different MTL subregions measured using high-resolution post-mortem MRI. Tau, TAR DNA-binding protein 43 (TDP-43), amyloid-β and α-synuclein pathology were rated on a scale of 0 (absent)-3 (severe) in the hippocampus and entorhinal cortex (ERC) of 58 individuals with and without neurodegenerative diseases (median age 75. Read More

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Symptom-Related Differential Neuroimaging Biomarkers in Children with Corpus Callosum Abnormalities.

Cereb Cortex 2021 Jul 21. Epub 2021 Jul 21.

Division of Newborn Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.

We aimed to identify symptom-related neuroimaging biomarkers for patients with dysgenesis of the corpus callosum (dCC) by summarizing neurological symptoms reported in clinical evaluations and correlating them with retrospectively collected structural/diffusion brain magnetic resonance imaging (MRI) measures from 39 patients/controls (mean age 8.08 ± 3.98). Read More

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Neuroimaging correlates of brain injury in Wilson's disease: a multimodal, whole-brain MRI study.

Brain 2021 Jul 20. Epub 2021 Jul 20.

Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London, WC1N 1PJ, UK.

Wilson's disease is an autosomal-recessive disorder of copper metabolism with neurological and hepatic presentations. Chelation therapy is used to 'de-copper' patients but neurological outcomes remain unpredictable. A range of neuroimaging abnormalities have been described and may provide insights into disease mechanisms, in addition to prognostic and monitoring biomarkers. Read More

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Longitudinal neural connection detection using a ferritin-encoding adeno-associated virus vector and in vivo MRI method.

Hum Brain Mapp 2021 Jul 20. Epub 2021 Jul 20.

Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, China.

The investigation of neural circuits is important for interpreting both healthy brain function and psychiatric disorders. Currently, the architecture of neural circuits is always investigated with fluorescent protein encoding neurotropic virus and ex vivo fluorescent imaging technology. However, it is difficult to obtain a whole-brain neural circuit connection in living animals, due to the limited fluorescent imaging depth. Read More

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Application of an integrated radio-frequency/shim coil technology for signal recovery in fMRI.

Magn Reson Med 2021 Jul 20. Epub 2021 Jul 20.

Brain Imaging and Analysis Center, Duke University, Durham, North Carolina, USA.

Purpose: Gradient-echo echo-planar imaging (EPI), which is typically used for blood oxygenation level-dependent (BOLD) functional MRI (fMRI), suffers from distortions and signal loss caused by localized B inhomogeneities. Such artifacts cannot be effectively corrected for with the low-order spherical harmonic (SH) shim coils available on most scanners. The integrated parallel reception, excitation, and shimming (iPRES) coil technology allows radiofrequency (RF) and direct currents to flow on each coil element, enabling imaging and localized B shimming with one coil array. Read More

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T MRI at 3T of cartilage and menisci in patients with hyperuricemia: initial findings.

Skeletal Radiol 2021 Jul 21. Epub 2021 Jul 21.

Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions; School of Radiation Medicine and Protection, Medical College of Soochow University; School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Suzhou, 215123, Jiangsu, China.

Objective: To compare and evaluate T values of compartmental femorotibial cartilage and subregional menisci in patients with hyperuricemia at 3T.

Materials And Methods: Thirty-two subjects were included in this study and subdivided into two subgroups: 15 healthy controls (3 females, 12 males; mean age = 45.3 ± 10. Read More

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Impact of the Sound of Magnetic Resonance Imaging Pulse Sequences in Awake Mice.

J Appl Anim Welf Sci 2021 Jul 21:1-14. Epub 2021 Jul 21.

Neuroplasticity and Neural Activity Lab, Champalimaud Foundation, Lisbon, Portugal.

Magnetic resonance imaging (MRI) is a research field of high interest as the implementation of new imaging modalities can significantly improve clinical diagnosis of several human pathologies. Awake nonhuman animals in the laboratory are being used in MRI pre-clinical systems for the validation of new imaging techniques, but animal welfare concerns emerge as MRI pulse sequences produce extremely loud sounds, up to 120 dB. Consequently, it is unclear how stressful these sounds are to the animals. Read More

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Examining the Feasibility of Quantifying Receptor Availability Using Cross-Modality Paired-Agent Imaging.

Mol Imaging Biol 2021 Jul 20. Epub 2021 Jul 20.

Thayer School of Engineering, Dartmouth College, 03755, Hanover, NH, USA.

Purpose: The ability to noninvasively quantify receptor availability (RA) in solid tumors is an aspirational goal of molecular imaging, often challenged by the influence of non-specific accumulation of the contrast agent. Paired-agent imaging (PAI) techniques aim to compensate for this effect by imaging the kinetics of a targeted agent and an untargeted isotype, often simultaneously, and comparing the kinetics of the two agents to estimate RA. This is usually accomplished using two spectrally distinct fluorescent agents, limiting the technique to superficial tissues and/or preclinical applications. Read More

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Differentiating white matter measures that protect against vs. predispose to bipolar disorder and other psychopathology in at-risk youth.

Neuropsychopharmacology 2021 Jul 20. Epub 2021 Jul 20.

Department of Psychiatry, University of Pittsburgh School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.

Bipolar disorder (BD) is highly heritable. Identifying objective biomarkers reflecting pathophysiological processes predisposing to, versus protecting against BD, can help identify BD risk in offspring of BD parents. We recruited 21 BD participants with a first-degree relative with BD, 25 offspring of BD parents, 27 offspring of comparison parents with non-BD psychiatric disorders, and 32 healthy offspring of healthy parents. Read More

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A multispeaker dataset of raw and reconstructed speech production real-time MRI video and 3D volumetric images.

Sci Data 2021 07 20;8(1):187. Epub 2021 Jul 20.

Ming Hsieh Department of Electrical and Computer Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, California, USA.

Real-time magnetic resonance imaging (RT-MRI) of human speech production is enabling significant advances in speech science, linguistics, bio-inspired speech technology development, and clinical applications. Easy access to RT-MRI is however limited, and comprehensive datasets with broad access are needed to catalyze research across numerous domains. The imaging of the rapidly moving articulators and dynamic airway shaping during speech demands high spatio-temporal resolution and robust reconstruction methods. Read More

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Effects of eight neuropsychiatric copy number variants on human brain structure.

Transl Psychiatry 2021 Jul 20;11(1):399. Epub 2021 Jul 20.

Douglas Research Centre, McGill University, Montréal, QC, Canada.

Many copy number variants (CNVs) confer risk for the same range of neurodevelopmental symptoms and psychiatric conditions including autism and schizophrenia. Yet, to date neuroimaging studies have typically been carried out one mutation at a time, showing that CNVs have large effects on brain anatomy. Here, we aimed to characterize and quantify the distinct brain morphometry effects and latent dimensions across 8 neuropsychiatric CNVs. Read More

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Combined Treatment With Pembrolizumab and Allogenic BK Virus-Specific T Cells in Progressive Multifocal Leukoencephalopathy: A Case Report.

Neurol Neuroimmunol Neuroinflamm 2021 Jul 20;8(5). Epub 2021 Jul 20.

From the Department of Neurology (R.W., T.K., B.H., M.D.), Klinikum rechts der Isar, Technical University Munich; Medical Department III for Hematology and Oncology (S.H., M.V.), Klinikum rechts der Isar, Technical University Munich; Institute for Transfusion Medicine (B.E.-V.), Hannover Medical School; Department of Pediatric Hematology and Oncology (B.M.-K.), Hannover Medical School; Department of Neuroradiology (J.S.K.), Klinikum Rechts der Isar, Technical University Munich; Unilabs A/S (A.P.), Copenhagen, Denmark; Institute of Experimental Neuroimmunology (T.K.), Klinikum rechts der Isar, Technical University of Munich; and Munich Cluster for Systems Neurology (SyNergy) (T.K., B.H.), Germany.

Objective: We report a combination of BK virus-specific T cells and pembrolizumab as a treatment option in progressive multifocal leukoencephalopathy (PML).

Results: A 57-year-old male patient diagnosed with PML presented a fast-progressing right hemiparesis, aphasia, and cognitive deficits. Brain MRI showed a severe leukoencephalopathy with diffusion restriction. Read More

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COVID-19 complicated by immune thrombocytopaenic purpura and internal jugular vein thrombosis.

BMJ Case Rep 2021 Jul 20;14(7). Epub 2021 Jul 20.

Haemato-Oncology, Barts Health NHS Trust, London, UK.

A 61-year-old woman who had tested positive for COVID-19 in the community 5 days prior to admission presented with new onset severe headache and mild shortness of breath. She had an acute reduction in her platelet counts from 153×10⁹/L to 5×10⁹/L. She was diagnosed with immune thrombocytopenia purpura and after treatment with intravenous immunoglobulin, her platelet count increased to 15×10⁹/L. Read More

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Usefulness of readout-segmented EPI-based diffusion tensor imaging of lacrimal gland for detection and disease staging in thyroid-associated ophthalmopathy.

BMC Ophthalmol 2021 Jul 20;21(1):281. Epub 2021 Jul 20.

Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Address: No. 300, Guangzhou Rd, Gulou district, Nanjing, P.R. China.

Background: Dysfunction of lacrimal gland (LG) gains increasing attention in patients with thyroid-associated ophthalmopathy (TAO), while the underlying pathological change is still not fully established. This study aimed to evaluate the utility of readout-segmented echo-planar imaging (rs-EPI)-based diffusion tensor imaging (DTI) in non-invasively detecting microstructural alterations of LG in patients with TAO, as well as in discriminating disease activity.

Methods: Thirty TAO patients and 15 age- and sex- matched healthy controls, who underwent rs-EPI-based DTI, were retrospectively enrolled. Read More

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Correlation of PET/CT and Brain MRI Findings in Human African Trypanosomiasis Encephalitis.

Clin Nucl Med 2021 Jul 20. Epub 2021 Jul 20.

From the Russell H. Morgan Department of Radiology and Radiological Science Pathology Department, Johns Hopkins University School of Medicine Division of Nuclear Medicine and Molecular Imaging, Johns Hopkins Medical Institutions, Baltimore, MD.

Abstract: A 49-year-old woman from Cameroon presented with history of several months of worsening headache, lethargy, left arm weakness, and generalized lymphadenopathy. Brain MRI demonstrated multifocal signal abnormality and enhancement involving the bilateral basal ganglia and cerebral white matter. FDG PET/CT performed as part of lymphadenopathy evaluation demonstrated patchy areas of increased metabolic activity of the brain parenchyma. Read More

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Healthy dietary intake moderates the effects of age on brain iron concentration and working memory performance.

Neurobiol Aging 2021 Jun 22;106:183-196. Epub 2021 Jun 22.

Department of Neuroscience, College of Medicine, University of Kentucky, Lexington, KY, USA; Sanders-Brown Center on Aging, College of Medicine, University of Kentucky, Lexington, KY, USA; Magnetic Resonance Imaging and Spectroscopy Center, College of Medicine, University of Kentucky, Lexington, KY, USA. Electronic address:

Age-related brain iron accumulation is linked with oxidative stress, neurodegeneration and cognitive decline. Certain nutrients can reduce brain iron concentration in animal models, however, this association is not well established in humans. Moreover, it remains unknown if nutrition can moderate the effects of age on brain iron concentration and/or cognition. Read More

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Prognostic value of neonatal EEG following therapeutic hypothermia in survivors of hypoxic-ischemic encephalopathy.

Clin Neurophysiol 2021 Jul 1;132(9):2091-2100. Epub 2021 Jul 1.

Neonatal Intensive Care Unit, Elizabeth Garrett Anderson Wing, University College London Hospitals, London WC1E 6DB, UK; Department of Neuroscience, Physiology & Pharmacology, University College London, London WC1E 6BT, UK. Electronic address:

Objective: Early prediction of neurological deficits following neonatal hypoxic-ischemic encephalopathy (HIE) may help to target support. Neonatal animal models suggest that recovery following hypoxia-ischemia depends upon cortical bursting. To test whether this holds in human neonates, we correlated the magnitude of cortical bursting during recovery (≥postnatal day 3) with neurodevelopmental outcomes. Read More

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MRI appearance of adjunct surgical material used in spine surgery.

Spine J 2021 Jul 17. Epub 2021 Jul 17.

Department of Radiology, Balgrist University Hospital, University of Zurich, Switzerland.

Background Context: Early postoperative MR images are frequently necessary after spine surgery. The appearance of commonly used adjunct hemostatic agents and dural sealants in MR images has not been systematically evaluated.

Purpose: The purpose of this experimental study was to systematically analyze and describe the characteristics of the most commonly applied hemostatic agents and dural sealants in spine surgery on early postoperative MR images. Read More

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