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Arterial spin labeling

Bing Wu, Yi Yang, Shuai Zhou, Wei Wang, Zizhen Wang, Gang Hu, Jianghong He, Xinhuai Wu
Purpose: Diagnostic error is common among patients with vegetative state (VS) and minimally conscious state (MCS). The purpose of this article is to use three-dimensional pseudo-continuous arterial spin labeling (pcASL) to compare cerebral blood flow (CBF) patterns in patients in MCS with those in VS. Methods: Patients meeting MCS and VS criteria were identified. Two post-labeling delay (PLD) time pcASL on 3.0-Tesla magnetic resonance imaging scanner system were performed with patients in the resting awake state...
2018: Frontiers in Neurology
Shiteng Suo, Lan Zhang, Hui Tang, Qihong Ni, Suqin Li, Haimin Mao, Xiangyu Liu, Shengyun He, Jianxun Qu, Qing Lu, Jianrong Xu
BACKGROUND: Noninvasive cardiovascular magnetic resonance (CMR) techniques including arterial spin labeling (ASL), blood oxygenation level-dependent (BOLD), and intravoxel incoherent motion (IVIM), are capable of measuring tissue perfusion-related parameters. We sought to evaluate and compare these three CMR techniques in characterizing skeletal muscle perfusion in lower extremities and to investigate their abilities to diagnose and assess the severity of peripheral arterial disease (PAD)...
March 19, 2018: Journal of Cardiovascular Magnetic Resonance
Nobuyuki Kosaka, Yasuhiro Fujiwara, Tetsuji Kurokawa, Tsuyoshi Matsuda, Masayuki Kanamoto, Naoyuki Takei, Kenji Takata, Jin Takahashi, Yoshio Yoshida, Hirohiko Kimura
OBJECTIVES: We evaluated the vascularity of retained products of conception (RPOC) using arterial spin-labeling magnetic resonance imaging (ASL-MRI) to clarify the clinical feasibility of this approach. MATERIALS AND METHODS: A pulsed-continuous ASL sequence with echo-planar imaging (EPI) acquisitions was used. Ten consecutive patients with RPOC were enrolled. All ASL images were evaluated visually and semiquantitatively and compared with the findings of Doppler ultrasound (US) and dynamic contrast-enhanced MRI (DCE-MRI)...
March 16, 2018: Magma
S A Amukotuwa, M P Marks, G Zaharchuk, F Calamante, R Bammer, N Fischbein
BACKGROUND AND PURPOSE: Intracranial dural arteriovenous fistulas carry a risk of substantial neurologic complications but can be difficult to detect on structural MR imaging and TOF-MRA. The purpose of this study was to assess the accuracy and added value of 3D pseudocontinuous arterial spin-labeling MR imaging for the detection of these lesions. MATERIALS AND METHODS: This retrospective study included 39 patients with a dural arteriovenous fistula and 117 controls who had undergone both DSA and MR imaging with pseudocontinuous arterial spin-labeling...
March 15, 2018: AJNR. American Journal of Neuroradiology
Katherine L Wright, Yun Jiang, Dan Ma, Douglas C Noll, Mark A Griswold, Vikas Gulani, Luis Hernandez-Garcia
In this study, the acquisition of ASL data and quantification of multiple hemodynamic parameters was explored using a Magnetic Resonance Fingerprinting (MRF) approach. A pseudo-continuous ASL labeling scheme was used with pseudo-randomized timings to acquire the MRF ASL data in a 2.5 min acquisition. A large dictionary of MRF ASL signals was generated by combining a wide range of physical and hemodynamic properties with the pseudo-random MRF ASL sequence and a two-compartment model. The acquired signals were matched to the dictionary to provide simultaneous quantification of cerebral blood flow, tissue time-to-peak, cerebral blood volume, arterial time-to-peak, B1 , and T1...
March 12, 2018: Magnetic Resonance Imaging
Peiying Liu, Ying Qi, Zixuan Lin, Qiyong Guo, Xiaoming Wang, Hanzhang Lu
Abnormal cerebral blood flow (CBF) is implicated in several neonatal and infant diseases. However, measurement of CBF in this population remains difficult and has not been used in routine clinical MRI. Arterial spin labeling (ASL) methods suffer from both low SNR and poor quantification when applied to very young children. Furthermore, rapid change in brain physiology in this age range makes it difficult to choose sequence parameters such as labeling pulse flip angle and post labeling delay. Phase-contrast (PC) MRI is another approach to measure flow...
March 10, 2018: NeuroImage
Katsuya Komatsu, Masahiko Wanibuchi, Takeshi Mikami, Yukinori Akiyama, Satoshi Iihoshi, Kei Miyata, Toshiya Sugino, Kengo Suzuki, Aya Kanno, Shouhei Noshiro, Shunya Ohtaki, Nobuhiro Mikuni
BACKGROUND: Preoperative evaluation of malignancy in gliomas is important for surgical planning, particularly to determine if a 1,3-bis-2-chloroethyl-1-nitrosourea wafer should be placed into the tumor cavity. In some cases, the intraoperative pathological diagnosis of World Health Organization grade differs from the final diagnosis. Supplemental methods in addition to the routine contrast tomography or magnetic resonance imaging sequences may provide a more accurate preoperative diagnosis...
March 9, 2018: World Neurosurgery
Dong Zhang, Pengcheng Xu, Hongyu Qiao, Xin Liu, Liangping Luo, Wenhua Huang, Heye Zhang, Changzheng Shi
BACKGROUND: Cerebrovascular events are frequently associated with hemodynamic disturbance caused by internal carotid artery (ICA) stenosis. It is challenging to determine the ischemia-related carotid stenosis during the intervention only using digital subtracted angiography (DSA). Inspired by the performance of well-established FFRct technique in hemodynamic assessment of significant coronary stenosis, we introduced a pressure-based carotid arterial functional assessment (CAFA) index generated from computational fluid dynamic (CFD) simulation in DSA data, and investigated its feasibility in the assessment of hemodynamic disturbance preliminarily using pressure-wired measurement and arterial spin labeling (ASL) MRI as references...
March 12, 2018: Biomedical Engineering Online
Rick P F Wolthusen, Garth Coombs, Emily A Boeke, Stefan Ehrlich, Stephanie N DeCross, Shahin Nasr, Daphne J Holt
BACKGROUND: Delusions are a defining and common symptom of psychotic disorders. Recent evidence suggests that subclinical and clinical delusions may represent distinct stages on a phenomenological and biological continuum. However, few studies have tested whether subclinical psychotic experiences are associated with neural changes that are similar to those observed in clinical psychosis. For example, it is unclear if overactivity of the hippocampus, a replicated finding of neuroimaging studies of schizophrenia, is also present in individuals with subclinical psychotic symptoms...
February 2018: Biological Psychiatry: Cognitive Neuroscience and Neuroimaging
Lirong Yan, Collin Y Liu, Koon-Pong Wong, Sung-Cheng Huang, Wendy J Mack, Kay Jann, Giovanni Coppola, John M Ringman, Danny J J Wang
Autosomal dominant Alzheimer's disease (ADAD) is a small subset of Alzheimer's disease that is genetically determined with 100% penetrance. It provides a valuable window into studying the course of pathologic processes that leads to dementia. Arterial spin labeling (ASL) MRI is a potential AD imaging marker that non-invasively measures cerebral perfusion. In this study, we investigated the relationship of cerebral blood flow measured by pseudo-continuous ASL (pCASL) MRI with measures of cerebral metabolism (FDG PET) and amyloid deposition (Pittsburgh Compound B (PiB) PET)...
2018: NeuroImage: Clinical
Cen Zhang, John A Detre, Scott E Kasner, Brett Cucchiara
Objective: The objective of this study is to determine whether structural features of the vertebrobasilar arterial system are related to migraine. Background: Alterations in cerebral vascular structure and function have been associated with migraine, possibly mediated by hypoperfusion and/or endothelial dysfunction triggering cortical spreading depression. Vessel tortuosity, in particular, has been associated with both altered hemodynamics and endothelial function...
2018: Frontiers in Neurology
D Keszthelyi, Q Aziz, J K Ruffle, O O'Daly, D Sanders, K Krause, S C Williams, M A Howard
BACKGROUND: Traditional psychometric measures aimed at characterizing the pain experience often show considerable overlap, due to interlinked affective and modulatory processes under central nervous system control. Neuroimaging studies have been employed to investigate this complexity of pain processing, in an attempt to provide a quantifiable, adjunctive description of pain perception. In this exploratory study, we examine psychometric and neuroimaging data from 38 patients with painful osteoarthritis of the carpometacarpal joint...
March 9, 2018: European Journal of Pain: EJP
Lu-Ping Li, Jon Thacker, Wei Li, Huan Tan, Chi Wang, Orly Kohn, Stuart Sprague, Pottumarthi Prasad
BACKGROUND: Identification of patients with progressive chronic kidney disease (CKD) and those likely to respond to candidate therapeutics is urgently needed. Functional MRI measurements have shown promise. However, knowledge about the consistency of the measurements is essential to conduct longitudinal studies. PURPOSE/HYPOTHESIS: To investigate the consistency of repeated functional MRI measurements in healthy subjects. STUDY TYPE: Prospective, longitudinal study...
March 8, 2018: Journal of Magnetic Resonance Imaging: JMRI
Junghun Cho, Youngwook Kee, Pascal Spincemaille, Thanh D Nguyen, Jingwei Zhang, Ajay Gupta, Shun Zhang, Yi Wang
PURPOSE: To map the cerebral metabolic rate of oxygen (CMRO2 ) by estimating the oxygen extraction fraction (OEF) from gradient echo imaging (GRE) using phase and magnitude of the GRE data. THEORY AND METHODS: 3D multi-echo gradient echo imaging and perfusion imaging with arterial spin labeling were performed in 11 healthy subjects. CMRO2 and OEF maps were reconstructed by joint quantitative susceptibility mapping (QSM) to process GRE phases and quantitative blood oxygen level-dependent (qBOLD) modeling to process GRE magnitudes...
March 7, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Yoshihito Tanaka, Yusuke Inoue, Yutaka Abe, Hiroki Miyatake, Hirofumi Hata
The aim of this study was to investigate the reliability of cerebral blood flow (CBF) measurements obtained by 3D pseudo-continuous arterial spin labeling (pCASL) imaging according to imaging parameters, scanner model, and field strength. We acquired 3D pCASL images in 12 healthy volunteers using four different scanners: two 3.0 T scanners and two 1.5 T scanners. Reliability was evaluated using intraclass correlation coefficient. Our results indicate that the influence of the post-labeling delay and scanner model on CBF measurements should be taken into consideration...
March 3, 2018: Clinical Imaging
Iain D Croall, Daniel J Tozer, Barry Moynihan, Usman Khan, John T O'Brien, Robin G Morris, Victoria C Cambridge, Thomas R Barrick, Andrew M Blamire, Gary A Ford, Hugh S Markus
Importance: Blood pressure (BP) lowering is considered neuroprotective in patients with cerebral small vessel disease; however, more intensive regimens may increase cerebral hypoperfusion. This study examined the effect of standard vs intensive BP treatment on cerebral perfusion in patients with severe small vessel disease. Objective: To investigate whether standard vs intensive BP lowering over 3 months causes decreased cerebral perfusion in small vessel disease...
March 5, 2018: JAMA Neurology
Mohamed Almuqbil, Michael J Rivkin, Masanori Takeoka, Edward Yang, Lance H Rodan
GLUT1 deficiency syndrome (GLUT1DS) is a well described neurometabolic disorder that results from impaired glucose transport into the central nervous system. GLUT1DS classically presents with infantile-onset epilepsy, progressive microcephaly, developmental delay, ataxia, dystonia, and spasticity, but a minority of patients may manifest with paroxysmal non-epileptic phenomena including hemiparesis (Wang et al., 2002). We report for the first time cerebral perfusion changes during an acute episode of hemiparesis in a 9 year old child with GLUT1DS...
February 19, 2018: European Journal of Paediatric Neurology: EJPN
James R Larkin, Manon A Simard, Alexandre A Khrapitchev, James A Meakin, Thomas W Okell, Martin Craig, Kevin J Ray, Peter Jezzard, Michael A Chappell, Nicola R Sibson
Cerebral blood flow is an important parameter in many diseases and functional studies that can be accurately measured in humans using arterial spin labelling (ASL) MRI. However, although rat models are frequently used for preclinical studies of both human disease and brain function, rat CBF measurements show poor consistency between studies. This lack of reproducibility is due, partly, to the smaller size and differing head geometry of rats compared to humans, as well as the differing analysis methodologies employed and higher field strengths used for preclinical MRI...
January 1, 2018: Journal of Cerebral Blood Flow and Metabolism
Russell Knutsen, Scott C Beeman, Thomas J Broekelmann, Delong Liu, Kit Man Tsang, Attila Kovacs, Li Ye, Joshua Danback, Anderson Watson, Amanda Wardlaw, Jessica Wagenseil, Joel R Garbow, Michael Shoykhet, Beth A Kozel
Increased vascular stiffness correlates with higher risk of cardiovascular complications in aging adults. Elastin insufficiency, as observed in patients with Williams-Beuren syndrome or with familial supravalvular aortic stenosis, also increases vascular stiffness and leads to arterial narrowing. We used Eln+/- mice to test the hypothesis that pathologically increased vascular stiffness with concomitant arterial narrowing leads to decreased blood flow to end organs such as the brain. We also hypothesized that drugs which remodel arteries and increase lumen diameter would improve flow...
March 2, 2018: American Journal of Physiology. Heart and Circulatory Physiology
Zixuan Lin, Yang Li, Pan Su, Deng Mao, Zhiliang Wei, Jay J Pillai, Abhay Moghekar, Matthias van Osch, Yulin Ge, Hanzhang Lu
PURPOSE: Many brain diseases are associated with an alteration in blood-brain barrier (BBB) and its permeability. Current methods using contrast agent are primarily sensitive to major leakage of BBB to macromolecules, but may not detect subtle changes in BBB permeability. The present study aims to develop a novel non-contrast MRI technique for the assessment of BBB permeability to water. METHODS: The central principle is that by measuring arterially labeled blood spins that are drained into cerebral veins, water extraction fraction (E) and permeability-surface-area product (PS) of BBB can be determined...
March 1, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
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