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Arterial spin labelling

Duygu Tosun, Norbert Schuff, Gil D Rabinovici, Nagehan Ayakta, Bruce L Miller, William Jagust, Joel Kramer, Michael M Weiner, Howard J Rosen
OBJECTIVE: To compare the values of arterial spin-labeled (ASL) MRI and fluorodeoxyglucose (FDG) PET in the diagnosis of behavioral variant of frontotemporal dementia (bvFTD) and Alzheimer's disease (AD). METHODS: Partial least squares logistic regression was used to identify voxels with diagnostic value in cerebral blood flow (CBF) and cerebral metabolic rate of glucose (CMRgl) maps from patients with bvFTD (n = 32) and AD (n = 28), who were compared with each other and with cognitively normal controls (CN, n = 15)...
October 2016: Annals of Clinical and Translational Neurology
A Venkatraman, A Khawaja, A K Bag, M Mirza, J P Szaflarski, S Pati
Lateralized Periodic Discharges (LPDs) are commonly seen on EEG in critically-ill patients. They are often associated with seizures, but some patients may have them without seizures. Therefore, they are considered to lie in the ictal-interictal continuum. When ictal, they require multiple antiepileptic drugs to treat effectively, which can expose the patient to iatrogenic complications. Therefore, optimal management is controversial. We present here two cases where perfusion-weighted Magnetic Resonance Imaging (pMRI) was useful in distinguishing ictal from interictal LPDs...
October 5, 2016: Journal of Clinical Neurophysiology: Official Publication of the American Electroencephalographic Society
Nolan S Hartkamp, Reinoud P H Bokkers, M J P van Osch, Gert J de Borst, Jeroen Hendrikse
BACKGROUND AND PURPOSE: To assess the effect of unilateral large vessel disease upon the cerebral hemodynamic autoregulatory status in the basal ganglia of patients with steno-occlusive internal carotid artery (ICA) disease. MATERIALS AND METHODS: Twenty-five healthy volunteers and 38 patients with a unilateral symptomatic steno-occlusive ICA lesion and were investigated; 20 with a stenosis >50% and 18 with an occlusion. Cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) were assessed with pseudo-continuous arterial spin labeling (ASL) magnetic resonance (MR) imaging before and after administration of acetazolamide...
October 12, 2016: Journal of Neuroradiology. Journal de Neuroradiologie
Yash V Tiwari, Jianfei Lu, Qiang Shen, Bianca Cerqueira, Timothy Q Duong
Diffusion-weighted arterial spin labeling magnetic resonance imaging has recently been proposed to quantify the rate of water exchange (Kw) across the blood-brain barrier in humans. This study aimed to evaluate the blood-brain barrier disruption in transient (60 min) ischemic stroke using Kw magnetic resonance imaging with cross-validation by dynamic contrast-enhanced magnetic resonance imaging and Evans blue histology in the same rats. The major findings were: (i) at 90 min after stroke (30 min after reperfusion), group Kw magnetic resonance imaging data showed no significant blood-brain barrier permeability changes, although a few animals showed slightly abnormal Kw Dynamic contrast-enhanced magnetic resonance imaging confirmed this finding in the same animals...
October 14, 2016: Journal of Cerebral Blood Flow and Metabolism
Junya Hatakeyama, Toshiharu Yanagisawa, Erina Kudo, Shuntaro Togashi, Hiroaki Shimizu
Progressive cerebral infarction in patients with hemorrhagic onset of moyamoya disease is rare, and a treatment strategy is not well established. Here, we report a case that was successfully treated with emergency bypass surgery. A 58-year-old woman presented with a sudden disturbance of consciousness and right-sided hemiparesis. Computed tomography(CT)showed intraventricular hemorrhage involving the head of the left caudate nucleus. Ventricular drainage was immediately performed, and the patient was treated conservatively...
October 2016: No Shinkei Geka. Neurological Surgery
Sebastian Walther, Lea Schäppi, Andrea Federspiel, Stephan Bohlhalter, Roland Wiest, Werner Strik, Katharina Stegmayer
Catatonia is a psychomotor syndrome that not only frequently occurs in the context of schizophrenia but also in other conditions. The neural correlates of catatonia remain unclear due to small-sized studies. We therefore compared resting-state cerebral blood flow (rCBF) and gray matter (GM) density between schizophrenia patients with current catatonia and without catatonia and healthy controls. We included 42 schizophrenia patients and 41 controls. Catatonia was currently present in 15 patients (scoring >2 items on the Bush Francis Catatonia Rating Scale screening)...
October 11, 2016: Schizophrenia Bulletin
Li Zhao, Weiying Dai, Salil Soman, David Hackney, Eric Wong, Philip Robson, David Alsop
Functional imaging provides hemodynamic and metabolic information and is increasingly being incorporated into clinical diagnostic and research studies. Typically functional images have reduced signal-to-noise ratio and spatial resolution compared to other non-functional cross sectional images obtained as part of a routine clinical protocol. We hypothesized that enhancing visualization and interpretation of functional images with anatomic information could provide preferable quality and superior diagnostic value...
October 6, 2016: IEEE Transactions on Medical Imaging
Ying Li, Huaijun Liu, Jiping Yang, Xin Tian, Haiqing Yang, Zuojun Geng
AIM: Our objective is to explore key changes in brain functions in relation to minimal hepatic encephalopathy (MHE). Moreover, we incorporated both resting-state functional MRI (fMRI) and arterial spin labeling (ASL) to enhance the detection of MHE. METHODS: We conducted fMRI scanning for 56 MHE patients and 66 healthy controls. Region functional connectivity (FC) was carried out to assess the connectivity status between pair of regions among 90 brain regions. Additionally, blood flood (BF) status was measured by ASL for all subjects...
October 7, 2016: Hepatology Research: the Official Journal of the Japan Society of Hepatology
Ying Cui, Xia Liang, Hong Gu, Yuzheng Hu, Zhen Zhao, Xiang-Yu Yang, Cheng Qian, Yihong Yang, Gao-Jun Teng
To explore the effect of T2DM on cerebral perfusion, and the relationship between cerebral perfusion changes and cognitive impairment as well as diabetic variables, by using a whole-brain arterial spin-labeling (ASL) MRI technique. This prospective study was approved by the local institutional review board and was performed between November 2012 and October 2013. All subjects provided informed consent. Forty T2DM patients and 41 age-, sex- and education-matched healthy controls were included. Cerebral blood flow (CBF) map was obtained by pulsed ASL perfusion imaging at 3 T MRI...
October 6, 2016: Brain Imaging and Behavior
Tracy Ssali, Udunna C Anazodo, Yves Bureau, Bradley J MacIntosh, Matthias Günther, Keith St Lawrence
Although arterial spin labeling (ASL) is appealing for mapping long-term changes in functional activity, inter-sessional variations in basal blood flow, arterial transit times (ATTs), and alignment errors, can result in significant false activation when comparing images from separate sessions. By taking steps to reduce these sources of noise, this study assessed the ability of ASL to detect functional CBF changes between sessions. ASL data were collected in three sessions to image ATT, resting CBF and CBF changes associated with motor activation (7 participants)...
2016: PloS One
Koji Yamashita, Akio Hiwatashi, Osamu Togao, Kazufumi Kikuchi, Hiroo Yamaguchi, Yuriko Suzuki, Ryotaro Kamei, Ryo Yamasaki, Jun-Ichi Kira, Hiroshi Honda
PURPOSE: To evaluate cerebral blood flow (CBF) laterality derived from arterial spin labeling (ASL) in early-stage Parkinson's disease (PD) patients compared with those with advanced stages. MATERIALS AND METHODS: Thirty-eight patients with PD (21 patients in early stages, 17 patients in advanced stages) were retrospectively studied. The CBF maps derived from 3T ASL data were co-registered to the corresponding 3DT1WI using SPM 12 software. Caudate nucleus (CN), putamen (PT), globus pallidus (GP), and thalamus (TH) were manually traced on the representative axial slices of 3DT1WI...
October 3, 2016: Journal of Magnetic Resonance Imaging: JMRI
Randall B Stafford, Myung-Kyun Woo, Se-Hong Oh, Sudipto Dolui, Tiejun Zhao, Young-Bo Kim, John A Detre, Zang-Hee Cho, Jongho Lee
7 T arterial spin labeling (ASL) faces major challenges including the increased specific absorption rate (SAR) and increased B0 and B1 inhomogeneity. This work describes the design and implementation of a dual-coil system that allows for continuous ASL (CASL) at 7 T. This system consisted of an actively detunable eight-channel transceiver head coil, and a three-channel transceiver labeling coil. Four experiments were performed in 5 healthy subjects: (i) to demonstrate that active detuning during ASL labeling reduces magnetization transfer; (ii) to measure the B1 profile at the labeling plane; (iii) to quantify B0 off-resonance at the labeling plane; and (iv) to collect in vivo CASL data...
June 2016: International Journal of Imaging Systems and Technology
Anna E Leeuwis, Marije R Benedictus, Joost P A Kuijer, Maja A A Binnewijzend, Astrid M Hooghiemstra, Sander C J Verfaillie, Teddy Koene, Philip Scheltens, Frederik Barkhof, Niels D Prins, Wiesje M van der Flier
INTRODUCTION: We examined the association between decreased cerebral blood flow (CBF) and cognitive impairment in Alzheimer's disease (AD), mild cognitive impairment (MCI), and subjective cognitive decline (SCD). METHODS: We included 161 AD, 95 MCI, and 143 SCD patients from the Amsterdam Dementia Cohort. We used 3-T pseudo-continuous arterial spin labeling to estimate whole-brain and regional partial volume-corrected CBF. Neuropsychological tests covered global cognition and five cognitive domains...
September 28, 2016: Alzheimer's & Dementia: the Journal of the Alzheimer's Association
Paul Kyu Han, Seung Hong Choi, Sung-Hong Park
PURPOSE: To investigate the performance of control scans in pseudo-continuous ASL (pCASL) and propose strategies for improving sensitivity and reliability of pCASL. METHODS: The labeling efficiencies of pCASL with conventional control scan and distal control scan were investigated at various radiofrequency (RF) duration/spacing of 0.5/1-2/4 ms, mean slice-selection gradients (GSS ) of 1 and 0 mT/m, and total labeling durations of 1.5-3 s, through Bloch equation simulations and in vivo experiments...
September 30, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Leila M Soravia, Ariane Orosz, Simon Schwab, Masahito Nakataki, Roland Wiest, Andrea Federspiel
BACKGROUND: Imaging studies have provided evidence that cognitive-behavioral therapy (CBT) is able to change brain activation in phobic patients in response to threatening stimuli. The changes occurred in both emotion-generating and modulatory regions. In this study, we use a data-driven approach to explore resting state cerebral blood flow (CBF) measured by arterial spin labeling (ASL), before and after CBT. METHODS: Eight female patients with spider phobia were scanned before and 1 month after an exposure-based group therapy for spider phobia...
September 2016: Brain and Behavior
R M D'Ortenzio, S P Hojjat, R Vitorino, C G Cantrell, L Lee, A Feinstein, P O'Connor, T J Carroll, R I Aviv
BACKGROUND AND PURPOSE: Quantitative CBF usage as a biomarker for cognitive impairment and disease progression in MS is potentially a powerful tool for longitudinal patient monitoring. Dynamic susceptibility contrast perfusion with bookend T1-calibration (bookend technique) and pseudocontinuous arterial spin-labeling have recently been used for CBF quantification in relapsing-remitting MS. The noninvasive nature of pseudocontinuous arterial spin-labeling is advantageous over gadolinium-based techniques, but correlation between the techniques is not well-established in the context of MS...
September 29, 2016: AJNR. American Journal of Neuroradiology
Jeff Boissoneault, Janelle Letzen, Song Lai, Michael E Robinson, Roland Staud
Studies using arterial spin labelling (ASL) have shown that individuals with chronic fatigue syndrome (CFS) have decreased regional cerebral blood flow, which may be associated with changes in functional neural networks. Indeed, recent studies indicate disruptions in functional connectivity (FC) at rest in chronically fatigued patients including perturbations in static FC (sFC), that is average FC at rest between several brain regions subserving neurocognitive, motor and affect-related networks. Whereas sFC often provides information of functional network reorganization in chronic illnesses, investigations of temporal changes in functional connectivity between multiple brain areas may shed light on the dynamic characteristics of brain network activation associated with such maladies...
September 28, 2016: Clinical Physiology and Functional Imaging
H Han, Z Liang, L Li, Z Wang, J A Detre, L Xing
No abstract text is available yet for this article.
October 1, 2016: International Journal of Radiation Oncology, Biology, Physics
Floris Groenendaal, Linda S de Vries
In the past brain imaging of term infants with HIE was performed with cranial ultrasound (cUS) and computed tomography (CT). Both techniques have several disadvantages, sensitivity and specificity are limited compared to MRI, and CT makes use of radiation.At present MRI including diffusion weighted MRI during the first week of life, has become the method of choice for imaging infants with HIE. In addition to imaging, blood vessels and blood flow can be visualized using MR angiography, MR venography, and arterial spin labeling...
September 27, 2016: Pediatric Research
Samuel Verges, Thomas Rupp, Marjorie Villien, Laurent Lamalle, Irène Troprés, Camille Poquet, Jan M Warnking, François Estève, Pierre Bouzat, Alexandre Krainik
OBJECTIVE: Hypoxic exposure in healthy subjects can induce acute mountain sickness including headache, lethargy, cerebral dysfunction, and substantial cerebral structural alterations which, in worst case, can lead to potentially fatal high altitude cerebral edema. Within this context, the relationships between high altitude-induced cerebral edema, changes in cerebral perfusion, increased brain parenchyma volume, increased intracranial pressure, and symptoms remain unclear. METHODS: In 11 subjects before and after 6 days at 4350 m, we performed multiparametric magnetic resonance investigations including anatomical, apparent diffusion coefficient and arterial spin labeling sequences...
2016: Frontiers in Physiology
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