TY - JOUR A1 - Huber, Stephan A1 - Haase, Axel A1 - Gleich, Bernhard T1 - Analysis of 2D NMR relaxation data using Chisholm approximations JF - Journal of Magnetic Resonance UR - https://doi.org/10.1016/j.jmr.2017.05.006 KW - Chisholm approximation KW - 2D NMR relaxation KW - Laplace inversion Y1 - 2017 UR - https://doi.org/10.1016/j.jmr.2017.05.006 SN - 1096-0856 VL - 2017 IS - 281 SP - 66 EP - 74 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Gómez Damián, Pedro A. A1 - Sperl, Jonathan I. A1 - Janich, Martin A. A1 - Khegai, Oleksandr A1 - Wiesinger, Florian A1 - Glaser, Steffen J. A1 - Haase, Axel A1 - Schwaiger, Markus A1 - Schulte, Rolf F. A1 - Menzel, Marion Irene T1 - Multisite Kinetic Modeling of 13C Metabolic MR Using [1-13C]Pyruvate JF - Radiology Research and Practice N2 - Hyperpolarized13C imaging allows real-timein vivomeasurements of metabolite levels. Quantification of metabolite conversion between [1-13C]pyruvate and downstream metabolites [1-13C]alanine, [1-13C]lactate, and [13C]bicarbonate can be achieved through kinetic modeling. Since pyruvate interacts dynamically and simultaneously with its downstream metabolites, the purpose of this work is the determination of parameter values through a multisite, dynamic model involving possible biochemical pathways present in MR spectroscopy. Kinetic modeling parameters were determined by fitting the multisite model to time-domain dynamic metabolite data. The results for different pyruvate doses were compared with those of different two-site models to evaluate the hypothesis that for identical data the uncertainty of a model and the signal-to-noise ratio determine the sensitivity in detecting small physiological differences in the target metabolism. In comparison to the two-site exchange models, the multisite model yielded metabolic conversion rates with smaller bias and smaller standard deviation, as demonstrated in simulations with different signal-to-noise ratio. Pyruvate dose effects observed previously were confirmed and quantified through metabolic conversion rate values. Parameter interdependency allowed an accurate quantification and can therefore be useful for monitoring metabolic activity in different tissues. UR - https://doi.org/10.1155/2014/871619 Y1 - 2014 UR - https://doi.org/10.1155/2014/871619 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-41646 SN - 2090-195X VL - 2014 PB - Hindawi CY - New York ER - TY - JOUR A1 - Huber, Stephan A1 - Min, Changwook A1 - Staat, Christoph A1 - Oh, Juhyun A1 - Castro, Cesar A1 - Haase, Axel A1 - Weissleder, Ralph A1 - Gleich, Bernhard A1 - Lee, Hakho T1 - Multichannel digital heteronuclear magnetic resonance biosensor JF - Biosensors and Bioelectronics UR - https://doi.org/10.1016/j.bios.2018.10.052 KW - Magnetic sensor KW - Biosensor KW - Nuclear magnetic resonance Y1 - 2019 UR - https://doi.org/10.1016/j.bios.2018.10.052 SN - 1873-4235 VL - 2019 IS - 126 SP - 240 EP - 248 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Coello, Eduardo A1 - Hafalir, Fatih S. A1 - Noeske, Ralph A1 - Menzel, Marion Irene A1 - Haase, Axel A1 - Menze, Bjoern H. A1 - Schulte, Rolf F. T1 - Overdiscrete echo-planar spectroscopic imaging with correlated higher-order phase correction JF - Magnetic Resonance in Medicine UR - https://doi.org/10.1002/mrm.28105 Y1 - 2019 UR - https://doi.org/10.1002/mrm.28105 SN - 1522-2594 VL - 84 IS - 1 SP - 11 EP - 24 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Wu, Mingming A1 - Mulder, Hendrik T. A1 - Baron, Paul A1 - Coello, Eduardo A1 - Menzel, Marion Irene A1 - van Rhoon, Gerard C. A1 - Haase, Axel T1 - Correction of motion-induced susceptibility artifacts and B0 drift during proton resonance frequency shift-based MR thermometry in the pelvis with background field removal methods JF - Magnetic Resonance in Medicine N2 - Purpose The linear change of the water proton resonance frequency shift (PRFS) with temperature is used to monitor temperature change based on the temporal difference of image phase. Here, the effect of motion-induced susceptibility artifacts on the phase difference was studied in the context of mild radio frequency hyperthermia in the pelvis. Methods First, the respiratory-induced field variations were disentangled from digestive gas motion in the pelvis. The projection onto dipole fields (PDF) as well as the Laplacian boundary value (LBV) algorithm were applied on the phase difference data to eliminate motion-induced susceptibility artifacts. Both background field removal (BFR) algorithms were studied using simulations of susceptibility artifacts, a phantom heating experiment, and volunteer and patient heating data. Results Respiratory-induced field variations were negligible in the presence of the filled water bolus. Even though LBV and PDF showed comparable results for most data, LBV seemed more robust in our data sets. Some data sets suggested that PDF tends to overestimate the background field, thus removing phase attributed to temperature. The BFR methods even corrected for susceptibility variations induced by a subvoxel displacement of the phantom. The method yielded successful artifact correction in 2 out of 4 patient treatment data sets during the entire treatment duration of mild RF heating of cervical cancer. The heating pattern corresponded well with temperature probe data. Conclusion The application of background field removal methods in PRFS-based MR thermometry has great potential in various heating applications and body regions to reduce motion-induced susceptibility artifacts that originate outside the region of interest, while conserving temperature-induced PRFS. In addition, BFR automatically removes up to a first-order spatial B0 drift. UR - https://doi.org/10.1002/mrm.28302 KW - B0 drift KW - background field removal KW - hyperthermia KW - motion KW - MR thermometry KW - susceptibility Y1 - 2020 UR - https://doi.org/10.1002/mrm.28302 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-18776 SN - 1522-2594 VL - 84 IS - 5 SP - 2495 EP - 2511 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Wu, Mingming A1 - Mulder, Hendrik T. A1 - Zur, Yuval A1 - Lechner-Greite, Silke A1 - Menzel, Marion Irene A1 - Paulides, Margarethus M. A1 - Rhoon, Gerard C. van A1 - Haase, Axel T1 - A phase-cycled temperature-sensitive fast spin echo sequence with conductivity bias correction for monitoring of mild RF hyperthermia with PRFS JF - Magnetic Resonance Materials in Physics, Biology and Medicine UR - https://doi.org/10.1007/s10334-018-0725-5 KW - MR thermometry KW - Hyperthermia KW - Proton resonance frequency shift KW - Fast spin echo KW - Double echo gradient echo KW - Intervention KW - Conductivity Y1 - 2018 UR - https://doi.org/10.1007/s10334-018-0725-5 SN - 1352-8661 VL - 32 IS - 3 SP - 369 EP - 380 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Sprenger, Tim A1 - Sperl, Jonathan I. A1 - Fernandez, Brice A1 - Haase, Axel A1 - Menzel, Marion Irene T1 - Real valued diffusion‐weighted imaging using decorrelated phase filtering JF - Magnetic Resonance in Medicine UR - https://doi.org/10.1002/mrm.26138 Y1 - 2016 UR - https://doi.org/10.1002/mrm.26138 SN - 1522-2594 SN - 0740-3194 VL - 77 IS - 2 SP - 559 EP - 570 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Sprenger, Tim A1 - Sperl, Jonathan I. A1 - Fernandez, Brice A1 - Golkov, Vladimir A1 - Eidner, Ines A1 - Sämann, Philipp G. A1 - Czisch, Michael A1 - Tan, Ek Tsoon A1 - Hardy, Christopher J. A1 - Marinelli, Luca A1 - Haase, Axel A1 - Menzel, Marion Irene T1 - Bias and precision analysis of diffusional kurtosis imaging for different acquisition schemes JF - Magnetic Resonance in Medicine UR - https://doi.org/10.1002/mrm.26008 Y1 - 2016 UR - https://doi.org/10.1002/mrm.26008 SN - 1522-2594 SN - 0740-3194 VL - 76 IS - 6 SP - 1684 EP - 1696 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Scholz, David Johannes A1 - Janich, Martin A. A1 - Koellisch, Ulrich A1 - Schulte, Rolf F. A1 - Ardenkjaer‐Larsen, Jan H. A1 - Frank, Annette A1 - Haase, Axel A1 - Schwaiger, Markus A1 - Menzel, Marion Irene T1 - Quantified pH imaging with hyperpolarized 13C-bicarbonate JF - Magnetic Resonance in Medicine UR - https://doi.org/10.1002/mrm.25357 Y1 - 2014 UR - https://doi.org/10.1002/mrm.25357 SN - 1522-2594 SN - 0740-3194 VL - 73 IS - 6 SP - 2274 EP - 2282 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Koellisch, Ulrich A1 - Laustsen, Christoffer A1 - Nørlinger, Thomas S. A1 - Østergaard, Jakob Appel A1 - Flyvbjerg, Allan A1 - Gringeri, Concetta V. A1 - Menzel, Marion Irene A1 - Schulte, Rolf F. A1 - Haase, Axel A1 - Stødkilde-Jørgensen, Hans T1 - Investigation of metabolic changes in STZ-induced diabetic rats with hyperpolarized [1-13C]acetate JF - Physiological Reports N2 - In the metabolism of acetate several enzymes are involved, which play an important role in free fatty acid oxidation. Fatty acid metabolism is altered in diabetes patients and therefore acetate might serve as a marker for pathological changes in the fuel selection of cells, as these changes occur in diabetes patients. Acetylcarnitine is a metabolic product of acetate, which enables its transport into the mitochondria for energy production. This study investigates whether the ratio of acetylcarnitine to acetate, measured by noninvasive hyperpolarized [1-13C]acetate magnetic resonance spectroscopy, could serve as a marker for myocardial, hepatic, and renal metabolic changes in rats with Streptozotocin (STZ)-induced diabetes in vivo. We demonstrate that the conversion of acetate to acetylcarnitine could be detected and quantified in all three organs of interest. More interestingly, we found that the hyperpolarized acetylcarnitine to acetate ratio was independent of blood glucose levels and prolonged hyperglycemia following diabetes induction in a type-1 diabetes model. UR - https://doi.org/10.14814/phy2.12474 Y1 - 2015 UR - https://doi.org/10.14814/phy2.12474 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-44529 SN - 2051-817X VL - 3 IS - 8 PB - Wiley CY - Weinheim ER -