1,402 results match your criteria asl perfusion


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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ICG fluorescence imaging in colorectal surgery: a snapshot from the ICRAL study group.

BMC Surg 2021 Apr 10;21(1):190. Epub 2021 Apr 10.

General Surgery Unit, CG Mazzoni Hospital, Ascoli Piceno, Italy.

Background: Fluorescence-guided visualization is a recently proposed technology in colorectal surgery. Possible uses include evaluating perfusion, navigating lymph nodes and searching for hepatic metastases and peritoneal spread. Despite the absence of high-level evidence, this technique has gained considerable popularity among colorectal surgeons due to its significant reliability, safety, ease of use and relatively low cost. Read More

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APOE moderates the effect of hippocampal blood flow on memory pattern separation in clinically normal older adults.

Hippocampus 2021 Apr 9. Epub 2021 Apr 9.

Department of Neurology, Memory and Aging Center, University of California, San Francisco (UCSF), San Francisco, California, USA.

Pattern separation, the ability to differentiate new information from previously experienced similar information, is highly sensitive to hippocampal structure and function and declines with age. Functional MRI studies have demonstrated hippocampal hyperactivation in older adults compared to young, with greater task-related activation associated with worse pattern separation performance. The current study was designed to determine whether pattern separation was sensitive to differences in task-free hippocampal cerebral blood flow (CBF) in 130 functionally intact older adults. Read More

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The Role of OCT Angiography in the Assessment of Epiretinal Macular Membrane.

J Ophthalmol 2021 24;2021:8866407. Epub 2021 Mar 24.

Department of Neurosciences, Psychology, Drug Research and Child Health Eye Clinic, University of Florence, AOU Careggi, Florence 50139, Italy.

Background: The aim of this observational study is to assess pre- and postoperative retinochoroidal vascular changes in patients undergoing epiretinal macular membrane (ERM) surgery by using optical coherence tomography angiography (OCTA).

Materials And Methods: 23 eyes affected by ERM and those which underwent phacovitrectomy associated with ERM peeling were enrolled. They were evaluated using structural OCT and OCTA before surgery and at 1, 3, and 6 months postoperatively. Read More

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Simultaneously acquired PET and ASL imaging biomarkers may be helpful in differentiating progression from pseudo-progression in treated gliomas.

Eur Radiol 2021 Mar 31. Epub 2021 Mar 31.

Service de Neuroradiologie Diagnostique et Fonctionnelle, Groupe Hospitalier Pitié-Salpêtrière C. Foix, 47-83 Boulevard de l'Hôpital, 75651, Paris Cedex 13, France.

Objectives: The aim of this work was investigating the methods based on coupling cerebral perfusion (ASL) and amino acid metabolism ([F]DOPA-PET) measurements to evaluate the diagnostic performance of PET/MRI in glioma follow-up.

Methods: Images were acquired using a 3-T PET/MR system, on a prospective cohort of patients addressed for possible glioma progression. Data were preprocessed with statistical parametric mapping (SPM), including registration on T1-weighted images, spatial and intensity normalization, and tumor segmentation. 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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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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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

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.

Authors:
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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Perfusion-weighted MRI in cerebral amyloid angiopathy-related transient focal neurological episodes.

Neurol Sci 2021 Mar 22. Epub 2021 Mar 22.

Neurology Unit, Ospedale del Mare, ASL Napoli 1 Centro, Via Enrico Russo, 80147, Napoli, Italy.

Introduction: Sporadic cerebral amyloid angiopathy (CAA) is a common age-related cerebral small vessel disease characterized by progressive ß-amyloid deposition in the walls of small cortical arteries, arterioles, and capillaries in the cerebral cortex and overlying leptomeninges. CAA-related transient focal neurological episodes (CAA-TFNEs) represent a challenging clinical feature interesting from a pathophysiological point of view.

Case Report: Here we present two cases of CAA-TFNEs in which we performed functional imaging with perfusion-weighted imaging MR and brain 18 F-FDG PET. Read More

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A Noninvasive Method for Quantifying Cerebral Metabolic Rate of Oxygen by Hybrid PET/MRI: Validation in a Porcine Model.

J Nucl Med 2021 Mar 19. Epub 2021 Mar 19.

Lawson Health Research Institute, Canada.

The gold standard for imaging the cerebral metabolic rate of oxygen (CMRO) is positron emission tomography (PET); however, it is an invasive and complex procedure that also requires correction for recirculating O-HO and the blood-borne activity. We propose a noninvasive reference-based hybrid PET/magnetic resonance imaging (MRI) method that uses functional MRI techniques to calibrate O-O-PET data. Here, PET/MR imaging of oxidative metabolism (PMROx) was validated in an animal model by comparison to PET-alone measurements. 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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ASL perfusion in atypical Japanese encephalitis.

Indian J Radiol Imaging 2020 Oct-Dec;30(4):536-539. Epub 2021 Jan 13.

Barnard Insitute of Radiology, Madras Medical College, Chennai, Tamil Nadu, India. E-mail:

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January 2021

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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Vitamin C Acutely Affects Brain Perfusion and Mastication-Induced Perfusion Asymmetry in the Principal Trigeminal Nucleus.

Front Syst Neurosci 2021 26;15:641121. Epub 2021 Feb 26.

Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Baronissi, Italy.

Prolonged mastication may induce an asymmetric modification of the local perfusion of the trigeminal principal nucleus. The aim of the present study was to evaluate the possible influence of vitamin C (vit. C) on such effect. Read More

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February 2021

Use of intravenous sodium bicarbonate in neonatal intensive care units in Italy: a nationwide survey.

Ital J Pediatr 2021 Mar 11;47(1):63. Epub 2021 Mar 11.

Neonatal Intensive Care Unit, Department of Neonatology, Bambino Gesù Children's Hospital, Rome, Italy.

Background: Metabolic Acidosis (MA) is a disturbance of the acid-base balance that can occur in preterm and critically ill term neonates due to different etiologies. Intravenous sodium bicarbonate (SB) has been traditionally used to correct such unbalance, despite the lack of evidence about its safety and efficacy. In literature, reported undesirable effects of treatment with SB in neonates include worsening of intracellular acidosis, impairment of myocardial function, cerebral blood flow fluctuations and intracranial hemorrhage. Read More

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Vessel length on SNAP MRA and TOF MRA is a potential imaging biomarker for brain blood flow.

Magn Reson Imaging 2021 Mar 6;79:20-27. Epub 2021 Mar 6.

Vascular Imaging Lab, Department of Radiology, University of Washington, Seattle, WA, United States; BioMolecular Imaging Center, Department of Radiology, University of Washington, Seattle, WA, United States.

Purpose: To explore feasibility of using the vessel length on time-of-flight (TOF) or simultaneous non-contrast angiography and intraplaque hemorrhage (SNAP) MRA as an imaging biomarker for brain blood flow, by using arterial spin labeling (ASL) perfusion imaging and 3D phase contrast (PC) quantitative flow imaging as references.

Methods: In a population of thirty subjects with carotid atherosclerotic disease, the visible intracranial arteries on TOF and SNAP were semi-automatically traced and the total length of the distal segments was calculated with a dedicated software named iCafe. ASL blood flow was calculated automatically using the recommended hemodynamic model. Read More

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Detection of Changes in Renal Blood Flow Using Arterial Spin Labeling MRI.

Am J Nephrol 2021 5;52(1):69-75. Epub 2021 Mar 5.

Department of Nephrology and Hypertension, University Hospital Erlangen, Erlangen, Germany,

Background: Alteration in kidney perfusion is an early marker of renal damage. The purpose of this study was to evaluate if changes in renal blood flow (RBF) could be detected using MRI with arterial spin labeling (ASL) technique.

Methods: RBF as assessed by cortical (CRBF), medullary, and total renal blood flow (TRBF) were measured by MRI with arterial spin labeling (ASL-MRI) using flow-sensitive alternating inversion recovery true fast imaging with steady-state precession sequence. Read More

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Glucose Control Has an Impact on Cerebral Blood Flow Alterations in Chronic Tinnitus Patients.

Front Neurosci 2020 4;14:623520. Epub 2021 Feb 4.

Department of Otolaryngology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.

Purpose: Both tinnitus and type 2 diabetes mellitus (T2DM) are linked with cognitive decline and brain dysfunction. This study used arterial spin labeling (ASL) perfusion functional magnetic resonance imaging (fMRI) to examine the abnormal cerebral blood flow (CBF) patterns existed in tinnitus patients and potential relationships between the abnormal CBF and cognitive performance. The impact of T2DM on CBF alterations in tinnitus patients was further explored. Read More

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February 2021

Crossed Cerebellar Diaschisis in Alzheimer's Disease Detected by Arterial Spin-labelling Perfusion MRI.

In Vivo 2021 Mar-Apr;35(2):1177-1183

Department of Neuroradiology, Universitätsmedizin Mannheim, University of Heidelberg, Mannheim, Germany;

Background: Crossed cerebellar diaschisis (CCD) is a phenomenon with depressed metabolism and hypoperfusion in the cerebellum. Using arterial spin-labelling perfusion weighted magnetic resonance imaging (ASL PWI), we investigated the frequency of CCD in patients with Alzheimer's disease (AD) and differences between patients with and without CCD.

Patients And Methods: In patients with AD who underwent a standardized magnetic resonance imaging including ASL PWI cerebral blood flow was evaluated in the cerebellum, and brain segmentation/volumetry was performed using mdbrain (mediaire GmbH, Berlin, Germany) and FSL FIRST (Functional Magnetic Resonance Imaging of the Brain Software Library). Read More

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December 2020

Cognitive behavioral based group psychotherapy focusing on repetitive negative thinking: Decreased uncontrollability of rumination is related to brain perfusion increases in the left dorsolateral prefrontal cortex.

J Psychiatr Res 2021 Apr 13;136:281-287. Epub 2021 Feb 13.

Department of Experimental Clinical and Health Psychology, Ghent University, Ghent, Belgium.

Repetitive negative thinking (RNT) is a core process underlying various psychiatric disorders. 'Uncontrollability of rumination (UOR)' is one the most maladaptive factors of rumination, but little is known on how cognitive behavioral focused RNT psychotherapy may alter brain activity. In a subsample of 47 patients suffering from RNT who also underwent brain imaging (registered RCT trial NCT01983033), we evaluated the effect of cognitive behavioral based group psychotherapy (CBGP) (n = 25) as compared to a delayed treatment control group (DTCG) (n = 22) on frontolimbic brain perfusion with a focus on UOR. Read More

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Can 3D Pseudo-Continuous Territorial Arterial Spin Labeling Effectively Diagnose Patients With Recanalization of Unilateral Middle Cerebral Artery Stenosis?

J Magn Reson Imaging 2021 Feb 21. Epub 2021 Feb 21.

Department of Radiology, The First Affiliated Hospital of Shandong First Medical University (Shandong Qianfoshan Hospital), Jinan, Shandong Province, 250014, China.

Background: Unilateral middle cerebral artery (MCA) stenosis, as an independent risk factor for stroke, requires an intervention operation for vessel recanalization. Accurate perfusion measurement is thus essential after the operation.

Purpose: To explore the feasibility of three-dimensional (3D) pseudo-continuous territorial arterial-spin-labeling (tASL) in evaluating MCA recanalization. Read More

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February 2021

Spatial dependency and the role of local susceptibility for velocity selective arterial spin labeling (VS-ASL) relative tagging efficiency using accelerated 3D radial sampling with a BIR-8 preparation.

Magn Reson Med 2021 Jul 21;86(1):293-307. Epub 2021 Feb 21.

Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin, USA.

Purpose: Velocity selective arterial spin labeling (VS-ASL) is a promising approach for non-contrast perfusion imaging that provides robustness to vascular geometry and transit times; however, VS-ASL assumes spatially uniform tagging efficiency. This work presents a mapping approach to investigate VS-ASL relative tagging efficiency including the impact of local susceptibility effects on a BIR-8 preparation.

Methods: Numerical simulations of tagging efficiency were performed to evaluate sensitivity to regionally varying local susceptibility gradients and blood velocity. Read More

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Sex and age-related differences in cerebral blood flow investigated using pseudo-continuous arterial spin labeling magnetic resonance imaging.

Aging (Albany NY) 2021 02 17;13(4):4911-4925. Epub 2021 Feb 17.

Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD 20892, USA.

Adequate cerebral blood flow (CBF) is essential to a healthy central nervous system (CNS). Previous work suggests that CBF differs between men and women, and declines with age and certain pathologies, but a highly controlled systematic study across a wide age range, and incorporating white matter (WM) regions, has not been undertaken. Here, we investigate age- and sex-related differences in CBF in gray matter (GM) and WM regions in a cohort ( = 80) of cognitively unimpaired individuals over a wide age range. Read More

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February 2021

Attenuated cerebral blood flow in frontolimbic and insular cortices in Alcohol Use Disorder: Relation to working memory.

J Psychiatr Res 2021 Apr 2;136:140-148. Epub 2021 Feb 2.

Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA, USA; Center for Health Sciences, SRI International, Menlo Park, CA, USA.

Chronic, excessive alcohol consumption is associated with cerebrovascular hypoperfusion, which has the potential to interfere with cognitive processes. Magnetic resonance pulsed continuous arterial spin labeling (PCASL) provides a noninvasive approach for measuring regional cerebral blood flow (CBF) and was used to study 24 men and women with Alcohol Use Disorder (AUD) and 20 age- and sex-matched controls. Two analysis approaches tested group differences: a data-driven, regionally-free method to test for group differences on a voxel-by-voxel basis and a region of interest (ROI) approach, which focused quantification on atlas-determined brain structures. Read More

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Sex-related differences in arterial spin-labelled perfusion of metabolically active brain structures in neonatal hypoxic-ischaemic encephalopathy.

Clin Radiol 2021 May 9;76(5):342-347. Epub 2021 Feb 9.

Department of Radiology, Children's Hospital of Philadelphia, Philadelphia, PA, USA; Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA. Electronic address:

Aim: To investigate the sex-related differences in arterial spin-labelled (ASL) perfusion of metabolically active brain structures in neonatal hypoxic-ischaemic encephalopathy (HIE).

Materials And Methods: Seventy-three term neonates were identified for a retrospective case-control study following an institutional review board (IRB) approved protocol. The cerebral pulsed arterial spin labelling values were compared by permutation test to identify metabolically active brain structures with significant perfusion changes between 10 male controls and eight female controls, and between 31 HIE males and 24 HIE females. Read More

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Cerebral blood flow and cerebrovascular reactivity are preserved in a mouse model of cerebral microvascular amyloidosis.

Elife 2021 Feb 12;10. Epub 2021 Feb 12.

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

Impaired cerebrovascular function is an early biomarker for cerebral amyloid angiopathy (CAA), a neurovascular disease characterized by amyloid-β accumulation in the cerebral vasculature, leading to stroke and dementia. The transgenic Swedish Dutch Iowa (Tg-SwDI) mouse model develops cerebral microvascular amyloid-β deposits, but whether this leads to similar functional impairments is incompletely understood. We assessed cerebrovascular function longitudinally in Tg-SwDI mice with arterial spin labeling (ASL)-magnetic resonance imaging (MRI) and laser Doppler flowmetry (LDF) over the course of amyloid-β deposition. Read More

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February 2021

Left ventricular ejection fraction and right atrial diameter are associated with deep regional CBF in arteriosclerotic cerebral small vessel disease.

BMC Neurol 2021 Feb 11;21(1):67. Epub 2021 Feb 11.

Department of Neurology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, China.

Background: Systemic cardiac hypoperfusion is a well-acknowledged contributor to ischemic leukoencephalopathy. However, it has remained elusive how atherosclerosis-mediated cardiac remodelling modifies cerebral perfusion homeostasis as well as neuroimaging burden in cerebral small vessel disease (CSVD) development.

Methods: This retrospective study identified 103 arteriosclerotic CSVD (aCSVD) patients (CSVD burden 0 ~ 1, n = 61 and CSVD burden 2 ~ 4, n = 42) from Sep. Read More

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February 2021

Repeatability of multinuclear interleaved acquisitions with nuclear Overhauser enhancement effect in dynamic experiments in the calf muscle at 3T.

Magn Reson Med 2021 Jul 9;86(1):115-130. Epub 2021 Feb 9.

NMR Laboratory, Neuromuscular Investigation Center, Institute of Myology, Paris, France.

Purpose: To evaluate the repeatability of multinuclear interleaved H/ P NMR dynamic acquisitions in skeletal muscle and the impact of nuclear Overhauser enhancement (nOe) on the P results at 3T in exercise-recovery and ischemia-hyperemia paradigms.

Methods: A H/ P interleaved pulse sequence was used to measure every 2.5 s a perfusion-weighted image, a map, a P spectrum and 32 H spectra sensitive to deoxymyoglobin. Read More

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