5,461 results match your criteria spin labeling

Mononitrate Isosorbide as an Adjunctive Therapy in Schizophrenia: A Randomized Controlled Crossover Trial.

J Clin Psychopharmacol 2021 Apr 14. Epub 2021 Apr 14.

From the Neuroscience and Behavioral Sciences Department, Ribeirao Preto Medical School, University of São Paulo (USP) National Institute for Science and Technology - Translational Medicine (INCT - TM), CNPq/FAPESP/CAPES Physics Department, FFCLRP, University of São Paulo (USP), São Paulo, Brazil Spinoza Centre for Neuroimaging Experimental and Applied Psychology, VU University, Amsterdam, the Netherlands Radiology Division, Department of Internal Medicine, Ribeirao Preto Medical School, University of São Paulo USP), São Paulo, Brazil Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada Department of Psychiatry, Interdisciplinary Lab of Clinical Neurosciences (LiNC), and Schizophrenia Program (PROESQ), Federal São Paulo University (Unifesp), São Paulo, Brazil.

Background: Schizophrenia is a complex disabling mental disorder, and many patients present poor response to available treatments. Accumulating evidence about the role of the glutamate/nitric oxide pathway in mediating the positive and negative symptoms of schizophrenia suggests potential benefits of drugs that modulate this system. The aim of this study was to test the efficacy of isosorbide mononitrate (ISMN) as an adjunctive therapy for symptomatic outpatients with schizophrenia. Read More

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Conventional and advanced MRI evaluation of brain vascular malformations.

J Neuroimaging 2021 Apr 15. Epub 2021 Apr 15.

MRI Unit, Radiology Department, HT Medica, Jaén, Spain.

Vascular malformations (VMs) of the central nervous system (CNS) include a wide range of pathological conditions related to intra and extracranial vessel abnormalities. Although some VMs show typical neuroimaging features, other VMs share and overlap pathological and neuroimaging features that hinder an accurate differentiation between them. Hence, it is not uncommon to misclassify different types of VMs under the general heading of arteriovenous malformations. Read More

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Arterial Spin Labeling Magnetic Resonance Imaging in Healthy Adults: Mathematical Model Fitting to Assess Age-Related Perfusion Pattern.

Korean J Radiol 2021 Apr 1. Epub 2021 Apr 1.

Department of Radiology, West China Hospital, Sichuan University, Chengdu, China.

Objective: To investigate the age-dependent changes in regional cerebral blood flow (CBF) in healthy adults by fitting mathematical models to imaging data.

Materials And Methods: In this prospective study, 90 healthy adults underwent pseudo-continuous arterial spin labeling imaging of the brain. Regional CBF values were extracted from the arterial spin labeling images of each subject. Read More

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Synthetic Approaches for 15N-labeled Hyperpolarized Heterocyclic Molecular Imaging Agents for 15N NMR Signal Amplification By Reversible Exchange in Microtesla Magnetic Fields.

Chemistry 2021 Apr 15. Epub 2021 Apr 15.

Wayne State University, Chemistry, 5101 Cass Ave, 48202, Detroit, UNITED STATES.

NMR hyperpolarization techniques enhance nuclear spin polarization by several orders of magnitude resulting in corresponding sensitivity gains. This massive sensitivity gain enables new applications ranging from studies of small molecules using high-resolution NMR spectroscopy to real-time metabolic imaging in vivo . Several hyperpolarization techniques exist for hyperpolarization of a large repertoire of nuclear spins, although 13 C- and 15 N- sites of biocompatible agents are the key targets due to their widespread in biochemical pathways. Read More

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Neurovascular coupling dysfunction in end-stage renal disease patients related to cognitive impairment.

J Cereb Blood Flow Metab 2021 Apr 14:271678X211007960. Epub 2021 Apr 14.

Department of Medical Imaging, First Affiliated Hospital of Xi'an, Jiaotong University, Xi'an, China.

We aimed to investigate the neurovascular coupling (NVC) dysfunction in end-stage renal disease (ESRD) patients related with cognitive impairment. Twenty-five ESRD patients and 22 healthy controls were enrolled. To assess the NVC dysfunctional pattern, resting-state functional MRI and arterial spin labeling were explored to estimate the coupling of spontaneous neuronal activity and cerebral blood perfusion based on amplitude of low-frequency fluctuation (ALFF)-cerebral blood flow (CBF), fractional ALFF (fALFF)-CBF, regional homogeneity (ReHo)-CBF, and degree centrality (DC)-CBF correlation coefficients. Read More

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New-onset lesions on MRI-DWI and cerebral blood flow changes on 3D-pCASL after carotid artery stenting.

Sci Rep 2021 Apr 13;11(1):8005. Epub 2021 Apr 13.

Department of Radiology, Chinese PLA General Hospital, Haidian District, Beijing, China.

This study aimed to investigate the relationship between the new-onset hyperintense lesions on diffusion-weighted images (DWI) and the changes of cerebral blood flow (CBF) before and after carotid artery stenting (CAS) in patients with symptomatic unilateral carotid artery stenosis. Twenty-four patients with symptomatic unilateral carotid stenosis (50-99%) were enrolled. Routine head magnetic resonance imaging and three-dimensional pseudo-continuous arterial spin labeling were taken 7 days before the surgery and for four consecutive days post CAS. Read More

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Rapamycin restores brain vasculature, metabolism, and blood-brain barrier in an inflammaging model.

Geroscience 2021 Apr 13. Epub 2021 Apr 13.

Oklahoma Nathan Shock Center for Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.

Rapamycin (RAPA) is found to have neuro-protective properties in various neuroinflammatory pathologies, including brain aging. With magnetic resonance imaging (MRI) techniques, we investigated the effect of RAPA in a lipopolysaccharide (LPS)-induced inflammaging model in rat brains. Rats were exposed to saline (control), or LPS alone or LPS combined with RAPA treatment (via food over 6 weeks). Read More

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Three-dimensional pulsed continuous arterial spin labeling and intravoxel incoherent motion imaging of nasopharyngeal carcinoma: correlations with Ki-67 proliferation status.

Quant Imaging Med Surg 2021 Apr;11(4):1394-1405

Pathology Department, The First People's Hospital of Foshan, Foshan, China.

Background: Recurrence and distant metastasis are still the main problems affecting the long-term prognosis of nasopharyngeal carcinoma (NPC) patients, and may be related to the Ki-67 proliferation status. We therefore explored the potential correlation between Ki-67 proliferation status in NPC with the parameters derived from two imaging techniques: three-dimensional pulsed continuous arterial spin labeling (3D pCASL) and intravoxel incoherent motion (IVIM).

Methods: Thirty-six patients with pathologically confirmed NPC were included, and the Ki-67 labeling index (LI) was measured by immunohistochemistry. Read More

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Longitudinal Trajectories of Regional Cerebral Blood Flow in Very Preterm Infants during Third Trimester Ex Utero Development Assessed with MRI.

Radiology 2021 Mar 30:202423. Epub 2021 Mar 30.

From the Division of Diagnostic Imaging and Radiology, Children's National Hospital, 111 Michigan Ave NW, Washington, DC 20010 (Z.Z., K.K., N.A., J.M., C.L.); Division of Fetal and Transitional Medicine, Children's National Hospital, Washington, DC (Z.Z., A.d.P., C.L.); Departments of Pediatrics (Z.Z., M.J., S.B., M.S., J.M., T.C., A.d.P., C.L.) and Radiology (Z.Z., J.M., C.L.) and Divisions of Neonatology (S.B., M.S.) and Neurology (T.C.), Children's National Hospital, George Washington University School of Medicine and Health Sciences, Washington, DC; Division of Biostatistics and Study Methodology, Children's National Research Institute, Washington, DC (M.J.).

Background The third trimester of gestation is a crucial phase of rapid brain development, but little has been reported on the trajectories of cerebral blood flow (CBF) in preterm infants in this period. Purpose To quantify regional CBF in very preterm infants longitudinally across the ex utero third trimester and to determine its relationship with clinical factors associated with brain injury and premature birth. Materials and Methods In this prospective study, very preterm infants were enrolled for three longitudinal MRI scans, and 22 healthy full-term infants were enrolled for one term MRI scan between November 2016 and February 2019. Read More

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Arterial Spin Labeling is a Useful MRI Method for Presurgical Evaluation in MRI-Negative Focal Epilepsy.

Brain Topogr 2021 Mar 30. Epub 2021 Mar 30.

Brno Epilepsy Center, Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic.

Arterial spin labeling (ASL) is an MRI technique measuring brain perfusion using magnetically labeled blood as a tracer. The clinical utility of ASL for presurgical evaluation in non-lesional epilepsy as compared with the quantitative analysis of interictal [F] fluorodeoxyglucose PET (FDG-PET) was studied. In 10 patients (4 female; median age 29 years) who underwent a complete presurgical evaluation followed by surgical resection, the presurgical FDG-PET and ASL scans were compared with the resection masks using asymmetry index (AI) maps. Read More

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Validation of Cerebral Blood Flow Connectivity as Imaging Prognostic Biomarker on Subcortical Stroke.

J Neurochem 2021 Mar 28. Epub 2021 Mar 28.

Department of MRI, Henan Key Laboratory of Magnetic Resonance Function and Molecular Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.

Stroke is a major cause of vascular cognitive dysfunction, such as memory impairment. We aimed to explore the neural substrates underlying verbal memory impairment in subcortical stroke patients by the methods of voxel-wise cerebral blood flow (CBF) and the functional covariance network (FCN). Sixty patients with chronic subcortical stroke and sixty normal controls (NCs) were recruited into this study. Read More

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A perfusion phantom for ASL MRI based on impinging jets.

Magn Reson Med 2021 Mar 27. Epub 2021 Mar 27.

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

Purpose: We present a novel perfusion phantom for validation of arterial spin labeled (ASL) perfusion MRI methods and protocols.

Methods: Impinging jets, driven by a peristaltic pump, were used to achieve perfusion-like mixing of magnetically labeled inflowing fluid within a perfusion compartment. The phantom was validated by varying pump rates and obtaining ASL-MRI data at multiple postlabeling delays using a pseudo-continuous ASL sequence with a 3D stack-of-spirals readout. Read More

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Use of Three-Dimensional Arterial Spin Labeling to Evaluate Renal Perfusion in Patients With Chronic Kidney Disease.

J Magn Reson Imaging 2021 Mar 26. Epub 2021 Mar 26.

Department of Radiology, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China.

Background: A noninvasive method for evaluating renal blood flow (RBF) in patients with chronic kidney disease (CKD) may have clinical value in disease staging, management, and prognostication.

Purpose: To evaluate effectiveness of three-dimensional pseudocontinuous arterial spin labeling (pCASL) and pulsed arterial spin labeling (PASL) in assessment of cortex and outer medulla (cortex/OM) RBF in CKD patients and healthy volunteers (HVs).

Study Type: Prospective, in a single institution. Read More

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Diagnostic Accuracy of Arterial Spin-Labeling MR Imaging in Detecting the Epileptogenic Zone: Systematic Review and Meta-analysis.

AJNR Am J Neuroradiol 2021 Mar 25. Epub 2021 Mar 25.

From the Department of Ultrasound (J.Z., X.H., J.X., H.W., F.D.), First Affiliated Hospital of Southern University of Science and Technology, Second Clinical College of Jinan University, Shenzhen Medical Ultrasound Engineering Center, Shenzhen People's Hospital, Shenzhen, China

Background: A noninvasive, safe, and economic imaging technique is required to identify epileptogenic lesions in the brain.

Purpose: Our aim was to perform a meta-analysis evaluating the accuracy of arterial spin-labeling in localizing the epileptic focus in the brain and the changes in the blood perfusion in these regions.

Data Sources: Our sources were the PubMed and EMBASE data bases. Read More

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Lower cerebral perfusion is associated with tau-PET in the entorhinal cortex across the Alzheimer's continuum.

Neurobiol Aging 2021 Feb 10;102:111-118. Epub 2021 Feb 10.

Institute for Stroke and Dementia Research, Klinikum der Universität München, Ludwig-Maximilians-Universität LMU, Munich, Germany; German Center for Neurodegenerative Diseases, Munich, Germany. Electronic address:

Alzheimer's disease (AD) is associated with reduced temporo-parietal cerebral blood flow (CBF). However, a substantial variability in CBF across the clinical spectrum of AD has been reported, possibly due to differences in primary AD pathologies. Here, we assessed CBF (ASL-MRI), tau (AV1451-PET) and amyloid (AV45/FBB-PET) in 156 subjects across the AD continuum. Read More

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February 2021

A Prospective, Longitudinal Magnetic Resonance Imaging Evaluation of Cerebrovascular Reactivity and Infarct Development in Patients With Intracranial Stenosis.

J Magn Reson Imaging 2021 Mar 24. Epub 2021 Mar 24.

Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA.

Background: Patients with symptomatic atherosclerotic and non-atherosclerotic (i.e., moyamoya) intracranial steno-occlusive disease experience high 2-year infarct rates. Read More

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ASL MRI and 18F-FDG-PET in autoimmune limbic encephalitis: clues from two paradigmatic cases.

Neurol Sci 2021 Mar 24. Epub 2021 Mar 24.

Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, Cattinara University Hospital ASUGI, University of Trieste, Strada di Fiume 447, 34149, Trieste, Italy.

Background: Autoimmune limbic encephalitis (LE) is a neurological condition characterized by seizures and cognitive dysfunction. Fluorine-18 fluorodeoxyglucose (18F-FDG-PET) has recently proved to be an important diagnostic tool in this condition since it may highlight brain metabolism abnormalities in a very early stage of the disease. Two main 18F-FDG-PET patterns have been described: the mixed hypermetabolic/hypometabolic and the neurodegenerative one. Read More

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Three-Dimensional Pseudo-Continuous Arterial Spin Labeling Parameters Distinguish Pediatric Medulloblastoma and Pilocytic Astrocytoma.

Nguyen Minh Duc

Front Pediatr 2020 2;8:598190. Epub 2021 Mar 2.

Doctoral Program, Department of Radiology, Hanoi Medical University, Ha Noi, Vietnam.

Arterial Spin Labeling (ASL), a perfusion assessment without using gadolinium-based contrast agents, is outstandingly advantageous for pediatric patients. The differentiation of medulloblastomas from pilocytic astrocytomas in children plays a significant role in determining treatment strategies and prognosis. This study aimed to assess the use of ASL parameters during the differentiation between pediatric medulloblastoma and pilocytic astrocytoma. Read More

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High-Resolution Magnetic Resonance Imaging (HR-MRI) Imaging Characteristics of Vertebral Artery Dissection with Negative MR Routine Scan and Hypoperfusion in Arterial Spin Labeling.

Med Sci Monit 2021 Mar 10;27:e929445. Epub 2021 Mar 10.

Department of Radiology, The First People's Hospital of Lianyungang, Xuzhou Medical University, Lianyungang, Jiangsu, China (mainland).

BACKGROUND Unruptured vertebral artery dissection (VAD) that causes ischemic infarction may require anticoagulant therapy or other treatments. However, anticoagulation therapy is not recommended for patients without ischemic infarction. To date, there has been no research on the imaging characteristics of patients with ischemic hypoperfusion that have a negative routine MRI scan. Read More

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Cholesterol and cholesterol bilayer domains inhibit binding of alpha-crystallin to the membranes made of the major phospholipids of eye lens fiber cell plasma membranes.

Exp Eye Res 2021 Mar 17;206:108544. Epub 2021 Mar 17.

Department of Physics, Boise State University, Boise, ID, 83725, USA; Biomolecular Sciences Graduate Program, Boise State University, Boise, ID, 83725, USA. Electronic address:

The concentration of α-crystallin decreases in the eye lens cytoplasm, with a corresponding increase in membrane-bound α-crystallin during cataract formation. The eye lens's fiber cell plasma membrane consists of extremely high cholesterol (Chol) content, forming cholesterol bilayer domains (CBDs) within the membrane. The role of high Chol content in the lens membrane is unclear. Read More

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Synthesis and N NMR Signal Amplification by Reversible Exchange of [ N]Dalfampridine at Microtesla Magnetic Fields.

Chemphyschem 2021 Mar 18. Epub 2021 Mar 18.

Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, Michigan 48202, United States.

Signal Amplification by Reversible Exchange (SABRE) technique enables nuclear spin hyperpolarization of wide range of compounds using parahydrogen. Here we present the synthetic approach to prepare N-labeled [ N]dalfampridine (4-amino[ N]pyridine) utilized as a drug to reduce the symptoms of multiple sclerosis. The synthesized compound was hyperpolarized using SABRE at microtesla magnetic fields (SABRE-SHEATH technique) with up to 2. Read More

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Detection of renal allograft fibrosis with MRI: arterial spin labeling outperforms reduced field-of-view IVIM.

Eur Radiol 2021 Mar 18. Epub 2021 Mar 18.

Department of Medical Imaging, Jinling Hospital, Clinical School of Southern Medical University, Nanjing, 210002, Jiangsu, China.

Objective: To compare the value of reduced field-of-view (FOV) intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) and arterial spin labeling (ASL) for assessing renal allograft fibrosis and predicting long-term dysfunction.

Methods: This prospective study included 175 renal transplant recipients undergoing reduced FOV IVIM DWI, ASL, and biopsies. Renal allograft fibrosis was categorized into ci0, ci1, ci2, and ci3 fibrosis according to biopsy results. Read More

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Cerebrovascular reactivity in retinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations.

J Cereb Blood Flow Metab 2021 Apr 17;41(4):831-840. Epub 2020 Jun 17.

Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.

Retinal Vasculopathy with Cerebral Leukoencephalopathy and Systemic manifestations (RVCL-S) is a small vessel disease caused by mutations. RVCL-S is characterized by retinal vasculopathy and brain white matter lesions with and without contrast enhancement. We aimed to investigate cerebrovascular reactivity (CVR) in RVCL-S. Read More

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Altered cerebral blood flow in patients with unilateral venous pulsatile tinnitus: an arterial spin labeling study.

Br J Radiol 2021 Apr 18;94(1120):20200990. Epub 2021 Mar 18.

Department of Radiology, Beijing Friendship Hospital, Capital Medical University, Beijing, China.

Objectives: Abnormal neuronal activity and functional connectivity have been reported in patients with venous pulsatile tinnitus (PT). As neuronal activity is closely coupled to regional brain perfusion, the purpose of this study was to investigate the cerebral blood flow (CBF) alterations in patients with unilateral venous PT using arterial spin labeling (ASL).

Methods: This study included patients with right-sided PT between January 2018 and July 2019. Read More

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Radiolabeled HER2-directed exosomes exhibit improved cell targeting and specificity.

Nanomedicine (Lond) 2021 03 17;16(7):553-567. Epub 2021 Mar 17.

Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran 14117-13116, Iran.

Here, we established a reliable strategy for generation and characterization of targeted radiolabeled exosomes for the detection of HER2-positive cells quantitatively. Targeted exosomes (T-exos) were radiolabeled by two different radiotracers, [Tc]Tc-HMPAO or [In]In-oxine. The labeling efficiency and stability were assessed using exosome exclusive spin columns. Read More

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A Concise Review of the Multimodality Imaging Features of Renal Cell Carcinoma.

Cureus 2021 Feb 8;13(2):e13231. Epub 2021 Feb 8.

Radiology, Mcgovern Medical School at Uthealth, Houston, USA.

The evaluation of renal cell carcinoma (RCC) is routinely performed using the multimodality imaging approach, including ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET). Ultrasonography is the most frequently used imaging modality for the initial diagnosis of renal masses. The modality of choice for the characterization of the renal mass is multiphasic CT. Read More

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February 2021

Recanalization after cerebral venous thrombosis. A randomized controlled trial of the safety and efficacy of dabigatran etexilate versus dose-adjusted warfarin in patients with cerebral venous and dural sinus thrombosis.

Int J Stroke 2021 Apr 4:17474930211006303. Epub 2021 Apr 4.

Faculty of Medicine, University Duisburg-Essen, Essen, Germany.

Background: The effect of different anticoagulants on recanalization after cerebral venous thrombosis has not been studied in a randomized controlled trial.

Methods: RE-SPECT CVT (ClinicalTrials.gov number: NCT02913326) was a Phase III, prospective, randomized, parallel-group, open-label, multicenter, exploratory trial with blinded endpoint adjudication. Read More

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Quantitative arterial spin labeling magnetic resonance imaging analysis of reversible cerebral vasoconstriction syndrome: A case series.

Headache 2021 Mar 15. Epub 2021 Mar 15.

Department of Neurology, Graduate School of Medicine, Nagoya City University, Aichi, Japan.

Objective: This study aimed to quantify chronological cerebral blood flow (CBF) changes using arterial spin labeling (ASL) magnetic resonance imaging in patients with reversible cerebral vasoconstriction syndrome (RCVS).

Background: Quantitative ASL analyses in RCVS have not been well described in the literature.

Methods: Quantification of ASL using an automated region-of-interest placement software and a 5-point visual scale of vasoconstriction severity was performed in five RCVS patients. Read More

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Associations of Serum Liver Function Markers With Brain Structure, Function, and Perfusion in Healthy Young Adults.

Front Neurol 2021 25;12:606094. Epub 2021 Feb 25.

Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Hefei, China.

Previous neuroimaging studies have demonstrated brain abnormalities in patients with hepatic diseases. However, the identified liver-brain associations are largely limited to disease-affected populations, and the nature and extent of such relations in healthy subjects remain unclear. We hypothesized that serum liver function markers within a normal level would affect brain properties. Read More

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February 2021