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Hyperpolarized MRI

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https://www.readbyqxmd.com/read/28290535/continuous-flow-dnp-polarizer-for-mri-applications-at-1-5%C3%A2-t
#1
V Denysenkov, M Terekhov, R Maeder, S Fischer, S Zangos, T Vogl, T F Prisner
Here we describe a new hyperpolarization approach for magnetic resonance imaging applications at 1.5 T. Proton signal enhancements of more than 20 were achieved with a newly designed multimode microwave resonator situated inside the bore of the imager and used for Overhauser dynamic nuclear polarization of the water proton signal. Different from other approaches in our setup the hyperpolarization is achieved continuously by liquid water flowing through the polarizer under continuous microwave excitation. With an available flow rate of up to 1...
March 14, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28272754/hyperpolarized-%C3%AE-1-13-c-gluconolactone-as-a-probe-of-the-pentose-phosphate-pathway
#2
Karlos X Moreno, Crystal E Harrison, Matthew E Merritt, Zoltan Kovacs, Craig R Malloy, A Dean Sherry
The pentose phosphate pathway (PPP) is thought to be upregulated in trauma (to produce excess NADPH) and in cancer (to provide ribose for nucleotide biosynthesis), but simple methods for detecting changes in flux through this pathway are not available. MRI of hyperpolarized (13) C-enriched metabolites offers considerable potential as a rapid, non-invasive tool for detecting changes in metabolic fluxes. In this study, hyperpolarized δ-[1-(13) C]gluconolactone was used as a probe to detect flux through the oxidative portion of the pentose phosphate pathway (PPPox ) in isolated perfused mouse livers...
March 8, 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/28266629/an-optimized-microfabricated-platform-for-the-optical-generation-and-detection-of-hyperpolarized-129-xe
#3
Daniel J Kennedy, Scott J Seltzer, Ricardo Jiménez-Martínez, Hattie L Ring, Nicolas S Malecek, Svenja Knappe, Elizabeth A Donley, John Kitching, Vikram S Bajaj, Alexander Pines
Low thermal-equilibrium nuclear spin polarizations and the need for sophisticated instrumentation render conventional nuclear magnetic resonance (NMR) spectroscopy and imaging (MRI) incompatible with small-scale microfluidic devices. Hyperpolarized (129)Xe gas has found use in the study of many materials but has required very large and expensive instrumentation. Recently a microfabricated device with modest instrumentation demonstrated all-optical hyperpolarization and detection of (129)Xe gas. This device was limited by (129)Xe polarizations less than 1%, (129)Xe NMR signals smaller than 20 nT, and transport of hyperpolarized (129)Xe over millimeter lengths...
March 7, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28262691/liquid-state-carbon-13-hyperpolarization-generated-in-an-mri-system-for-fast-imaging
#4
A B Schmidt, S Berner, W Schimpf, C Müller, T Lickert, N Schwaderlapp, S Knecht, J G Skinner, A Dost, P Rovedo, J Hennig, D von Elverfeldt, J-B Hövener
Hyperpolarized (HP) tracers dramatically increase the sensitivity of magnetic resonance imaging (MRI) to monitor metabolism non-invasively and in vivo. Their production, however, requires an extra polarizing device (polarizer) whose complexity, operation and cost can exceed that of an MRI system itself. Furthermore, the lifetime of HP tracers is short and some of the enhancement is lost during transfer to the application site. Here, we present the production of HP tracers in water without an external polarizer: by Synthesis Amid the Magnet Bore, A Dramatically Enhanced Nuclear Alignment (SAMBADENA) is achieved within seconds, corresponding to a hyperpolarization of ∼20%...
March 6, 2017: Nature Communications
https://www.readbyqxmd.com/read/28247437/hyperpolarized-129xe-mri-sensor-for-h2s
#5
Shengjun Yang, Yaping Yuan, Weiping Jiang, Lili Ren, He Deng, Louis-S Bouchard, Xin Zhou, Maili Liu
A new MRI molecular sensor for hydrogen sulfide detection and imaging using the nuclear spin resonance of hyperpolarized 129Xe is developed. The designed MRI sensor employs cryptophane for NMR sensing together with an azide group serving as a reaction site. It demonstrates a 'proof-of-concept' that fluorescent H2S probe can be linked to a xenon-binding cryptophane and thereby converted into an MRI probe, which could provide a very generalizable template.
February 28, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28237893/dynamic-nuclear-polarization-via-thermal-mixing-beyond-the-high-temperature-approximation
#6
W Th Wenckebach
Dynamic Nuclear Polarization (DNP) via the mechanism of thermal mixing has proven itself most powerful for the orientation of nuclear spins in polarized targets and hyperpolarization for magnetic resonance imaging (MRI). Unfortunately, theoretical descriptions of this mechanism have been limited to using-at least partially-the high temperature approximation, in which Boltzmann factors are expanded linearly. However, the high nuclear spin polarization required and obtained for these applications does not justify such approximations...
February 20, 2017: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/28152435/nmr-spin-lock-induced-crossing-slic-dispersion-and-long-lived-spin-states-of-gaseous-propane-at-low-magnetic-field-0-05t
#7
Danila A Barskiy, Oleg G Salnikov, Alexey S Romanov, Matthew A Feldman, Aaron M Coffey, Kirill V Kovtunov, Igor V Koptyug, Eduard Y Chekmenev
When parahydrogen reacts with propylene in low magnetic fields (e.g., 0.05T), the reaction product propane develops an overpopulation of pseudo-singlet nuclear spin states. We studied how the Spin-Lock Induced Crossing (SLIC) technique can be used to convert these pseudo-singlet spin states of hyperpolarized gaseous propane into observable magnetization and to detect (1)H NMR signal directly at 0.05T. The theoretical simulation and experimental study of the NMR signal dependence on B1 power (SLIC amplitude) exhibits a well-resolved dispersion, which is induced by the spin-spin couplings in the eight-proton spin system of propane...
January 21, 2017: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/28132845/use-of-hyperpolarized-helium-3-mri-to-assess-response-to-ivacaftor-treatment-in-patients-with-cystic-fibrosis
#8
Talissa A Altes, Mac Johnson, Meredith Fidler, Martyn Botfield, Nicholas J Tustison, Carlos Leiva-Salinas, Eduard E de Lange, Deborah Froh, John P Mugler
BACKGROUND: This pilot study evaluated the effect of short- and long-term ivacaftor treatment on hyperpolarized (3)He-magnetic resonance imaging (MRI)-defined ventilation defects in patients with cystic fibrosis aged ≥12years with a G551D-CFTR mutation. METHODS: Part A (single-blind) comprised 4weeks of ivacaftor treatment; Part B (open-label) comprised 48weeks of treatment. The primary outcome was change from baseline in total ventilation defect (TVD; total defect volume:total lung volume ratio)...
March 2017: Journal of Cystic Fibrosis: Official Journal of the European Cystic Fibrosis Society
https://www.readbyqxmd.com/read/28120553/what-makes-a-good-pediatric-transplant-lung-insights-from-in-vivo-lung-morphometry-with-hyperpolarized-3-he-magnetic-resonance-imaging
#9
Emily F Fishman, James D Quirk, Stuart C Sweet, Jason C Woods, David S Gierada, Mark S Conradi, Marilyn J Siegel, Dmitriy A Yablonskiy
Obtaining information on transplanted lung microstructure is an important part of the current care for monitoring transplant recipients. However, until now this information was only available from invasive lung biopsy. The objective of this study was to evaluate the use of an innovative non-invasive technique, in vivo lung morphometry with hyperpolarized ³He MRI-to characterize lung microstructure in the pediatric lung transplant population. This technique yields quantitative measurements of acinar airways' (alveolar ducts and sacs) parameters, such as acinar airway radii and alveolar depth...
January 24, 2017: Pediatric Transplantation
https://www.readbyqxmd.com/read/28112867/high-spatial-resolution-hyperpolarized-3-he-mri-of-the-rodent-lung-using-a-single-breath-x-centric-gradient-recalled-echo-approach
#10
Alexei V Ouriadov, Giles E Santyr
PURPOSE: Hyperpolarized (HP) gas MRI of the rodent lung is of great interest because of the increasing need for novel biomarkers with which to develop new therapies for respiratory diseases. The use of fast gradient-recalled echo (FGRE) for high-resolution HP gas rodent lung MRI is challenging as a result of signal loss caused by significant diffusion weighting, particularly in the larger airways. In this work, a modified FGRE approach is described for HP (3) He rodent lung MRI using a centric-out readout scheme (ie, x-centric), allowing high-resolution, density-weighted imaging...
January 23, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28106110/in-vivo-detection-of-cucurbit-6-uril-a-hyperpolarized-xenon-contrast-agent-for-a-xenon-magnetic-resonance-imaging-biosensor
#11
Francis T Hane, Tao Li, Peter Smylie, Raiili M Pellizzari, Jennifer A Plata, Brenton DeBoef, Mitchell S Albert
The Hyperpolarized gas Chemical Exchange Saturation Transfer (HyperCEST) Magnetic Resonance (MR) technique has the potential to increase the sensitivity of a hyperpolarized xenon-129 MRI contrast agent. Signal enhancement is accomplished by selectively depolarizing the xenon within a cage molecule which, upon exchange, reduces the signal in the dissolved phase pool. Herein we demonstrate the in vivo detection of the cucurbit[6]uril (CB6) contrast agent within the vasculature of a living rat. Our work may be used as a stepping stone towards using the HyperCEST technique as a molecular imaging modality...
January 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28079713/interrogating-idh-mutation-in-brain-tumor-magnetic-resonance-and-hyperpolarization
#12
Jingzhe Hu, Travis C Salzillo, Napapon Sailasuta, Frederick F Lang, Pratip Bhattacharya
Magnetic resonance spectroscopy (MRS) offers the possibility to noninvasively quantify 2HG concentration in the brain in the clinic, thereby serving as a valuable tool for patient-stratification as well as targeted treatment monitoring. Recently, hyperpolarized magnetic resonance techniques have opened up new opportunities for metabolic imaging not possible with conventional MRS in the brain. With over 10,000-fold increase in signal-to-noise ratio (SNR), dynamic metabolic processes can be interrogated in vivo with very high specificity by hyperpolarized MRI...
February 2017: Topics in Magnetic Resonance Imaging: TMRI
https://www.readbyqxmd.com/read/28079471/pre-implant-modeling-of-depth-lead-placement-in-white-matter-for-maximizing-the-extent-of-cortical-activation-during-direct-neurostimulation-therapy
#13
Leopoldo Cendejas Zaragoza, Richard W Byrne, Marvin A Rossi
INTRODUCTION: The objective of this work was to predict preoperatively the maximum extent to which direct stimulation therapy can propagate through an epileptic circuit for stabilizing refractory focal-onset epilepsy. A pre-surgical workflow is presented which comprises a computationally intensive process for calculating the volume of cortical activation (VOCA) surrounding cylindrical depth contacts virtually placed in white matter. The process employs an activation function (AF) derived from cable modeling of an axon...
March 2017: Neurological Research
https://www.readbyqxmd.com/read/28072398/transportable-hyperpolarized-metabolites
#14
Xiao Ji, Aurélien Bornet, Basile Vuichoud, Jonas Milani, David Gajan, Aaron J Rossini, Lyndon Emsley, Geoffrey Bodenhausen, Sami Jannin
Nuclear spin hyperpolarization of (13)C-labelled metabolites by dissolution dynamic nuclear polarization can enhance the NMR signals of metabolites by several orders of magnitude, which has enabled in vivo metabolic imaging by MRI. However, because of the short lifetime of the hyperpolarized magnetization (typically <1 min), the polarization process must be carried out close to the point of use. Here we introduce a concept that markedly extends hyperpolarization lifetimes and enables the transportation of hyperpolarized metabolites...
January 10, 2017: Nature Communications
https://www.readbyqxmd.com/read/28060330/hyperpolarized-13c-metabolic-magnetic-resonance-spectroscopy-and-imaging
#15
Eugen Kubala, Kim A Muñoz-Álvarez, Geoffrey Topping, Christian Hundshammer, Benedikt Feuerecker, Pedro A Gómez, Giorgio Pariani, Franz Schilling, Steffen J Glaser, Rolf F Schulte, Marion I Menzel, Markus Schwaiger
In the past decades, new methods for tumor staging, restaging, treatment response monitoring, and recurrence detection of a variety of cancers have emerged in conjunction with the state-of-the-art positron emission tomography with (18)F-fluorodeoxyglucose ([(18)F]-FDG PET). (13)C magnetic resonance spectroscopic imaging ((13)CMRSI) is a minimally invasive imaging method that enables the monitoring of metabolism in vivo and in real time. As with any other method based on (13)C nuclear magnetic resonance (NMR), it faces the challenge of low thermal polarization and a subsequent low signal-to-noise ratio due to the relatively low gyromagnetic ratio of (13)C and its low natural abundance in biological samples...
December 30, 2016: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28048395/we-fg-206-07-assessing-the-lung-function-of-patients-with-non-small-cell-lung-cancer-using-hyperpolarized-xenon-129-dissolved-phase-mri
#16
K Qing, J Mugler, Q Chen
PURPOSE: Hyperpolarized xenon-129 dissolved-phase MRI is the first imaging technique that allows 3-dimensional regional mapping of ventilation and gas uptake by tissue and blood the in human lung. Multiple outcome measures can be produced from this method. Existing studies in subjects with major lung diseases compared to healthy controls demonstrated high sensitivities of this method to pulmonary physiological factors including ventilation, alveolar tissue density, surface-to-volume ratio, pulmonary perfusion and gas-blood barrier thickness...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28047750/we-fg-206-08-pulmonary-functional-imaging-biomarkers-of-nsclc-to-guide-and-optimize-functional-lung-avoidance-radiotherapy
#17
Khadija Sheikh, Dante Pi Capaldi, Douglas A Hoover, David A Palma, Brian P Yaremko, Grace Parraga
PURPOSE: Functional lung avoidance radiotherapy promises optimized therapy planning by minimizing dose to well-functioning lung and maximizing dose to the rest of the lung. Patients with NSCLC commonly present with co-morbid COPD and heterogeneously distributed ventilation abnormalities stemming from emphysema, airways disease, and tumour burden. We hypothesized that pulmonary functional imaging methods may be used to optimize radiotherapy plans to avoid regions of well-functioning lung and significantly improve outcomes like quality-of-life and survival...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28047236/we-ab-202-07-ventilation-ct-voxel-level-comparison-with-hyperpolarized-helium-3-xenon-129-mri
#18
B Tahir, H Marshall, P Hughes, N Stewart, F Horn, G Collier, G Norquay, K Hart, J Swinscoe, M Hatton, J Wild, R Ireland
PURPOSE: To compare the spatial correlation of ventilation surrogates computed from inspiratory and expiratory breath-hold CT with hyperpolarized Helium-3 & Xenon-129 MRI in a cohort of lung cancer patients. METHODS: 5 patients underwent expiration & inspiration breath-hold CT. Xenon-129 & (1) H MRI were also acquired at the same inflation state as inspiratory CT. This was followed immediately by acquisition of Helium-3 & (1) H MRI in the same breath and at the same inflation state as inspiratory CT...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28046370/th-cd-202-09-free-breathing-proton-mri-functional-lung-avoidance-maps-to-guide-radiation-therapy
#19
D Capaldi, K Sheikh, D Hoover, B Yaremko, D Palma, G Parraga
PURPOSE: Pulmonary functional MRI using inhaled gas contrast agents was previously investigated as a way to identify well-functioning lung in patients with NSCLC who are clinical candidates for radiotherapy. Hyperpolarized noble-gas ((3) He and (129) Xe) MRI has also been optimized to measure functional lung information, but for a number of reasons, the clinical translation of this approach to guide radiotherapy planning has been limited. As an alternative, free-breathing pulmonary 1H MRI using clinically available MRI systems and pulse sequences provides a non-contrast-enhanced method to generate both ventilation and perfusion maps...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28026061/detection-of-smoke-induced-pulmonary-lesions-by-hyperpolarized-129-xe-diffusion-kurtosis-imaging-in-rat-models
#20
Weiwei Ruan, Jianping Zhong, Yu Guan, Yi Xia, Xiuchao Zhao, Yeqing Han, Xianping Sun, Shiyuan Liu, Chaohui Ye, Xin Zhou
PURPOSE: To demonstrate that hyperpolarized (HP) xenon diffusion kurtosis imaging (DKI) is able to detect smoke-induced pulmonary lesions in rat models. METHODS: Multi-b DKI with hyperpolarized xenon was used for the first time in five smoke-exposed rats and five healthy rats. Additionally, DKI with b values of up to 80 s/cm(2) were used in two healthy rats to probe the critical b value (a limit beyond which the DKI cannot describe the non-Gaussian diffusion). RESULTS: The mean apparent diffusion coefficient (Dapp ) and diffusion kurtosis (Kapp ) extracted by the DKI model revealed significant changes in the smoke-exposed rats compared with those in the control group (P = 0...
December 27, 2016: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
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