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Hyperpolarized Xe

Le Zhang, Michael Antonacci, Alex Burant, Karl M Koshlap, Rosa Tamara Branca
A remote detection scheme utilizing the distant dipolar field interaction between two different spin species was proposed by Granwehr et al. [J. Magn. Reson. 176(2), 125 (2005)]. In that sequence (1)H spins were detected indirectly via their dipolar field interaction with (129)Xe spins, which served as the sensing spins. Here we propose a modification of the proposed detection scheme that takes advantage of the longer T1 relaxation time of xenon to create a long lasting dipolar field with which the fast relaxing (1)H spins are allowed to interact many times during a single acquisition...
November 21, 2016: Journal of Chemical Physics
Scott H Robertson, Rohan S Virgincar, Elianna A Bier, Mu He, Geoffrey M Schrank, Rose Marie Smigla, Craig Rackley, H Page McAdams, Bastiaan Driehuys
PURPOSE: The purpose of this work was to accurately characterize the spectral properties of hyperpolarized (129)Xe in patients with idiopathic pulmonary fibrosis (IPF) compared to healthy volunteers. METHODS: Subjects underwent hyperpolarized (129)Xe breath-hold spectroscopy, during which 38 dissolved-phase free induction decays (FIDs) were acquired after reaching steady state (echo time/repetition time = 0.875/50 ms; bandwidth = 8.06 kHz; flip angle≈22 °)...
November 8, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Alex Burant, Rosa Tamara Branca
The production of large volumes of highly polarized noble gases like helium and xenon is vital to applications of magnetic resonance imaging and spectroscopy with hyperpolarized (HP) gas in humans. In the past ten years, (129)Xe has become the gas of choice due to its lower cost, higher availability, relatively high tissue solubility, and wide range of chemical shift values. Though near unity levels of xenon polarization have been achieved in-cell using stopped-flow Spin Exchange Optical Pumping (SEOP), these levels are currently unmatched by continuous-flow SEOP methods...
October 26, 2016: Journal of Magnetic Resonance
Le Zhang, Alex Burant, Andrew McCallister, Victor Zhao, Karl M Koshlap, Simone Degan, Michael Antonacci, Rosa Tamara Branca
PURPOSE: To investigate the temperature dependence of the resonance frequency of lipid-dissolved xenon (LDX) and to assess the accuracy of LDX-based MR thermometry. METHODS: The chemical shift temperature dependence of water protons, methylene protons, and LDX was measured from samples containing tissues with varying fat contents using a high-resolution NMR spectrometer. LDX results were then used to acquire relative and absolute temperature maps in vivo and the results were compared with PRF-based MR thermometry...
October 19, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Tahreema N Matin, Najib Rahman, Annabel H Nickol, Mitchell Chen, Xiaojun Xu, Neil J Stewart, Tom Doel, Vicente Grau, James M Wild, Fergus V Gleeson
Purpose To compare lobar ventilation and apparent diffusion coefficient (ADC) values obtained with hyperpolarized xenon 129 ((129)Xe) magnetic resonance (MR) imaging to quantitative computed tomography (CT) metrics on a lobar basis and pulmonary function test (PFT) results on a whole-lung basis in patients with chronic obstructive pulmonary disease (COPD). Materials and Methods The study was approved by the National Research Ethics Service Committee; written informed consent was obtained from all patients. Twenty-two patients with COPD (Global Initiative for Chronic Obstructive Lung Disease stage II-IV) underwent hyperpolarized (129)Xe MR imaging at 1...
October 12, 2016: Radiology
Lukas Ebner, Jeff Kammerman, Bastiaan Driehuys, Mark L Schiebler, Robert V Cadman, Sean B Fain
In the last two decades, functional imaging of the lungs using hyperpolarized noble gases has entered the clinical stage. Both helium ((3)He) and xenon ((129)Xe) gas have been thoroughly investigated for their ability to assess both the global and regional patterns of lung ventilation. With advances in polarizer technology and the current transition towards the widely available (129)Xe gas, this method is ready for translation to the clinic. Currently, hyperpolarized (HP) noble gas lung MRI is limited to selected academic institutions; yet, the promising results from initial clinical trials have drawn the attention of the pulmonary medicine community...
September 16, 2016: European Journal of Radiology
Atsuomi Kimura, Yukiko Yamauchi, Shota Hodono, Neil James Stewart, Osamu Hosokawa, Yu Hagiwara, Hirohiko Imai, Hideaki Fujiwara
PURPOSE: The purpose of this work was to investigate disease progression and treatment response in a murine model of chronic obstructive pulmonary disease (COPD) using a preclinical hyperpolarized (129) Xe (HPXe) magnetic resonance imaging (MRI) strategy. METHODS: COPD phenotypes were induced in 32 mice by 10 weeks of exposure to cigarette smoke (CS) and lipopolysaccharide (LPS). Efficacy of ethyl pyruvate (EP), an anti-inflammatory drug, was investigated by administering EP to 16 of the 32 mice after 6 weeks of CS and LPS exposure...
September 30, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Lukas Ebner, Mu He, Rohan S Virgincar, Timothy Heacock, Suryanarayanan S Kaushik, Matthew S Freemann, H Page McAdams, Monica Kraft, Bastiaan Driehuys
OBJECTIVES: The aim of this study was to investigate ventilation in mild to moderate asthmatic patients and age-matched controls using hyperpolarized (HP) Xenon magnetic resonance imaging (MRI) and correlate findings with pulmonary function tests (PFTs). MATERIALS AND METHODS: This single-center, Health Insurance Portability and Accountability Act-compliant prospective study was approved by our institutional review board. Thirty subjects (10 young asthmatic patients, 26 ± 6 years; 3 males, 7 females; 10 older asthmatic patients, 64 ± 6 years; 3 males, 7 females; 10 healthy controls) were enrolled...
September 22, 2016: Investigative Radiology
Yanfei Wang, Ivan J Dmochowski
Molecular imaging holds considerable promise for elucidating biological processes in normal physiology as well as disease states, by determining the location and relative concentration of specific molecules of interest. Proton-based magnetic resonance imaging ((1)H MRI) is nonionizing and provides good spatial resolution for clinical imaging but lacks sensitivity for imaging low-abundance (i.e., submicromolar) molecular markers of disease or environments with low proton densities. To address these limitations, hyperpolarized (hp) (129)Xe NMR spectroscopy and MRI have emerged as attractive complementary methodologies...
October 18, 2016: Accounts of Chemical Research
Mu He, Bastiaan Driehuys, Loretta G Que, Yuh-Chin T Huang
RATIONALE AND OBJECTIVES: Ventilation heterogeneity is impossible to detect with spirometry. Alternatively, pulmonary ventilation can be imaged three-dimensionally using inhaled (129)Xe magnetic resonance imaging (MRI). To date, such images have been quantified primarily based on ventilation defects. Here, we introduce a robust means to transform (129)Xe MRI scans such that the underlying ventilation distribution and its heterogeneity can be quantified. MATERIALS AND METHODS: Quantitative (129)Xe ventilation MRI was conducted in 12 younger (24...
September 8, 2016: Academic Radiology
Shota Hodono, Hirohiko Imai, Yukiko Yamauchi, Ayano Kawamura, Hironobu Matsumoto, Shintaro Okumura, Hideaki Fujiwara, Atsuomi Kimura
The use of a quenching gas, isobutene, with a low vapor pressure was investigated to enhance the utility of hyperpolarized (129) Xe (HP Xe) MRI. Xenon mixed with isobutene was hyperpolarized using a home-built apparatus for continuously producing HP Xe. The isobutene was then readily liquefied and separated almost totally by continuous condensation at about 173 K, because the vapor pressure of isobutene (0.247 kPa) is much lower than that of Xe (157 kPa). Finally, the neat Xe gas was continuously delivered to mice by spontaneous inhalation...
October 2016: NMR in Biomedicine
Laura L Walkup, Robert P Thomen, Teckla G Akinyi, Erin Watters, Kai Ruppert, John P Clancy, Jason C Woods, Zackary I Cleveland
BACKGROUND: Hyperpolarized (129)Xe is a promising contrast agent for MRI of pediatric lung function, but its safety and tolerability in children have not been rigorously assessed. OBJECTIVE: To assess the feasibility, safety and tolerability of hyperpolarized (129)Xe gas as an inhaled contrast agent for pediatric pulmonary MRI in healthy control subjects and in children with cystic fibrosis. MATERIALS AND METHODS: Seventeen healthy control subjects (ages 6-15 years, 11 boys) and 11 children with cystic fibrosis (ages 8-16 years, 4 boys) underwent (129)Xe MRI, receiving up to three doses of (129)Xe gas prepared by either a commercially available or a homebuilt (129)Xe polarizer...
November 2016: Pediatric Radiology
Robert P Thomen, Laura L Walkup, David J Roach, Zackary I Cleveland, John P Clancy, Jason C Woods
BACKGROUND: Cystic fibrosis (CF) is a genetic disease which carries high morbidity and mortality from lung-function decline. Monitoring disease progression and treatment response in young patients is desirable, but serial imaging via CT is often considered prohibitive, and detailed functional information cannot be obtained using conventional imaging techniques. Hyperpolarized (129)Xe magnetic resonance imaging (MRI) can depict and quantify regional ventilation, but has not been investigated in pediatrics...
July 28, 2016: Journal of Cystic Fibrosis: Official Journal of the European Cystic Fibrosis Society
Keunhong Jeong, Chawita Netirojjanakul, Henrik K Munch, Jinny Sun, Joel A Finbloom, David E Wemmer, Alexander Pines, Matthew B Francis
We have synthesized targeted, selective, and highly sensitive (129)Xe NMR nanoscale biosensors using a spherical MS2 viral capsid, Cryptophane A molecules, and DNA aptamers. The biosensors showed strong binding specificity toward targeted lymphoma cells (Ramos line). Hyperpolarized (129)Xe NMR signal contrast and hyper-CEST (129)Xe MRI image contrast indicated its promise as highly sensitive hyperpolarized (129)Xe NMR nanoscale biosensor for future applications in cancer detection in vivo.
August 17, 2016: Bioconjugate Chemistry
Felix C Horn, Madhwesha Rao, Neil J Stewart, Jim M Wild
PURPOSE: To compare quantitative fractional ventilation measurements from multiple breath washout imaging (MBW-I) using hyperpolarized (3) He with both spoiled gradient echo (SPGR) and balanced steady-state free precession (bSSFP) three-dimensional (3D) pulse sequences and to evaluate the feasibility of MBW-I with hyperpolarized (129) Xe. METHODS: Seven healthy subjects were scanned using (3) He MBW-I with 3D SPGR and bSSFP sequences. Five also underwent MBW-I with (129) Xe...
July 12, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Yanfei Wang, Benjamin W Roose, Eugene J Palovcak, Vincenzo Carnevale, Ivan J Dmochowski
Molecular imaging holds considerable promise for elucidating biological processes in normal physiology as well as disease states, but requires noninvasive methods for identifying analytes at sub-micromolar concentrations. Particularly useful are genetically encoded, single-protein reporters that harness the power of molecular biology to visualize specific molecular processes, but such reporters have been conspicuously lacking for in vivo magnetic resonance imaging (MRI). Herein, we report TEM-1 β-lactamase (bla) as a single-protein reporter for hyperpolarized (HP) (129) Xe NMR, with significant saturation contrast at 0...
July 25, 2016: Angewandte Chemie
Jianping Zhong, Weiwei Ruan, Yeqing Han, Xianping Sun, Chaohui Ye, Xin Zhou
MRI of hyperpolarized media, such as (129)Xe and (3)He, shows great potential for clinical applications. The optimal use of the available spin polarization requires accurate flip angle calibrations and T1 measurements. Traditional flip angle calibration methods are time-consuming and suffer from polarization losses during T1 relaxation. In this paper, we propose a method to simultaneously calibrate flip angles and measure T1 in vivo during a breath-hold time of less than 4 seconds. We demonstrate the accuracy, robustness and repeatability of this method and contrast it with traditional methods...
2016: Scientific Reports
Talal Dahhan, Shiv S Kaushik, Mu He, Joseph G Mammarappallil, Victor F Tapson, Holman P McAdams, Thomas A Sporn, Bastiaan Driehuys, Sudarshan Rajagopal
The diagnosis of pulmonary vascular disease (PVD) is usually based on hemodynamic and/or clinical criteria. Noninvasive imaging of the heart and proximal vasculature can also provide useful information. An alternate approach to such criteria in the diagnosis of PVD is to image the vascular abnormalities in the lungs themselves. Hyperpolarized (HP) (129)Xe magnetic resonance imaging (MRI) is a novel technique for assessing abnormalities in ventilation and gas exchange in the lungs. We applied this technique to two patients for whom there was clinical suspicion of PVD...
March 2016: Pulmonary Circulation
Ozkan Doganay, Elaine Stirrat, Charles McKenzie, Rolf F Schulte, Giles E Santyr
PURPOSE: To assess the feasibility of hyperpolarized (HP) (129)Xe MRI for detection of early stage radiation-induced lung injury (RILI) in a rat model involving unilateral irradiation by assessing differences in gas exchange dynamics between irradiated and unirradiated lungs. METHODS: The dynamics of gas exchange between alveolar air space and pulmonary tissue (PT), PT and red blood cells (RBCs) was measured using single-shot spiral iterative decomposition of water and fat with echo asymmetry and least-squares estimation images of the right and left lungs of two age-matched cohorts of Sprague Dawley rats...
May 2016: Medical Physics
Madhwesha Rao, Neil J Stewart, Graham Norquay, Paul D Griffiths, Jim M Wild
PURPOSE: Upon inhalation, xenon diffuses into the bloodstream and is transported to the brain, where it dissolves in various compartments of the brain. Although up to five chemically distinct peaks have been previously observed in (129) Xe rat head spectra, to date only three peaks have been reported in the human head. This study demonstrates high resolution spectroscopy and chemical shift imaging (CSI) of (129) Xe dissolved in the human head at 1.5 Tesla. METHODS: A (129) Xe radiofrequency coil was built in-house and (129) Xe gas was polarized using spin-exchange optical pumping...
June 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
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