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Amirshaghaghi A, Cheng Z, Josephson L, Tsourkas A. Magnetic Nanoparticles. Mol Imaging 2021. [DOI: 10.1016/b978-0-12-816386-3.00033-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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McNabb E, Wong R, Noseworthy MD. Differentiating platinum coated brachytherapy seeds and gold fiducial markers with varying off-resonant frequency offsets. Magn Reson Imaging 2019; 60:68-75. [PMID: 30959177 DOI: 10.1016/j.mri.2019.04.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 03/14/2019] [Accepted: 04/04/2019] [Indexed: 11/29/2022]
Abstract
PURPOSE To develop an off-resonant frequency filtered method to selectively differentiate between implanted gold fiducial markers and platinum coated brachytherapy seeds. MATERIALS AND METHODS The magnetic susceptibilities for gold fiducial markers and brachytherapy seeds differ in magnitude and also in their signs, resulting in B0-field inhomogeneity patterns with opposite main lobes. A pulse sequence used to localize brachytherapy seeds with positive contrast, centre-out radial sampling with off-resonance reception (co-RASOR), was used to reconstruct images with a range of off-resonant frequency offsets. The proposed method utilizes two frequency filters to selectively reconstruct maximum intensity projections through band-pass regions where each seed has its maximal localized hyperintensity. Seeds were simulated and then placed in gel and tissue phantoms to validate the technique using orthogonal 2D slices with seeds both parallel and perpendicular to the B0-field. RESULTS Dual-plane 2D co-RASOR sequences were reconstructed off-resonance with applied frequency filters to create two projections displaying each seed, which were then colour-coded to negative and positive frequencies. Phantom validation showed that each seed contains its maximal CNR in opposing frequency regions as predicted. Local maxima can also appear in both negative and positive frequency regions. The relative difference between the signal of each seed and these local maxima ranged from 1.19 to 3.73, and an image threshold was determined in all cases. Tissue validation showed the technique differentiates seeds correctly and is limited by the hyperintensity patterns observed in the co-RASOR method. CONCLUSIONS Dual-plane co-RASOR offers sub-millimetre positive contrast from implanted seeds that contain unique off-resonant frequency maxima, which frequency filters can selectively differentiate.
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Affiliation(s)
- Evan McNabb
- McMaster School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada
| | - Raimond Wong
- Juravinski Cancer Centre, Hamilton, Ontario, Canada; Department of Oncology, McMaster University, Hamilton, Ontario, Canada; Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Michael D Noseworthy
- McMaster School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada; Department of Electrical and Computer Engineering, McMaster University, Hamilton, Ontario, Canada; Department of Radiology, McMaster University, Hamilton, Ontario, Canada; Imaging Research Centre, St. Joseph's Healthcare, Hamilton, Ontario, Canada.
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McNabb E, Wong R, Noseworthy MD. Resolution and registration in dual-plane co-RASOR MR. Phys Med Biol 2018; 63:215005. [PMID: 30260799 DOI: 10.1088/1361-6560/aae4d5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Magnetic resonance imaging (MRI) has superior soft tissue contrast and lower interobserver variability compared to computed tomography and advances in equipment and pseudo-CT estimation have allowed for MR-only radiation therapy planning. Dedicated MR sequences have been used to localize paramagnetic structures with positive contrast, and most implanted seeds are gold fiducial markers (GFMs). We used a fast, dual-plane co-RASOR sequence to localize implanted GFMs with positive contrast in phantom and tissue to assess their resolution and registration accuracy of registration to CT. Off-resonant reconstructions of co-RASOR images were able to resolve GFMs down to 5 mm apart at 12 cm FOV. No systematic biases were observed by comparing registration of co-RASOR and bSSFP to CT images in an MR-compatible Lego phantom with a set of highly visible known points. The standard deviations of the MR to CT distance errors were <0.5 mm in all directions. We separated the component due to registration by comparing the two MR sequences, which had a maximum standard deviation of 0.36 mm in the SI-direction. Registration using the positive contrast points in a porcine sample phantom showed increased errors, but co-RASOR still performs acceptably with a target registration error of <0.75 mm. The dual-plane co-RASOR sequence could then be used for both registration and image tracking when performing MR-only radiation therapy planning.
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Affiliation(s)
- Evan McNabb
- McMaster School of Biomedical Engineering, McMaster University, Hamilton, Ontario, Canada
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Bouwman JG, Custers BA, Bakker CJG, Viergever MA, Seevinck PR. isoPhasor: a generic and precise marker visualization, localization, and quantification method based on phase saddles in 3D MR imaging. Magn Reson Med 2018; 81:2038-2051. [PMID: 30346055 DOI: 10.1002/mrm.27493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 07/18/2018] [Accepted: 07/19/2018] [Indexed: 11/11/2022]
Abstract
PURPOSE To derive a generic approach for accurate localization and characterization of susceptibility markers in MRI, compatible with many common types of pulse sequences, sampling trajectories, and acceleration methods. THEORY AND METHODS A susceptibility marker's dipolar phase evolution creates 3 saddles in the phase gradient of the spatial encoding, for each sampled data point in k-space. The signal originating from these saddles can be focused at the location of the marker to create positive contrast. The required phase shift can be calculated from the scan parameters and the marker properties, providing a marker detection algorithm generic for different scan types. The method was validated numerically and experimentally for a broad range of spherical susceptibility markers (0.3 < radius < 1.6 mm, 10 < |∆χ| < 3300 ppm), under various conditions. RESULTS For all numerical and experimental phantoms, the average localization error was below one third of the voxel size, whereas the average error in magnetic strength quantification was 7%. The experiments included different pulse sequences (gradient echo, spin echo [SE], and free induction decay scans), sampling strategies (Cartesian, radial), and acceleration methods (echo planar imaging EPI, turbo SE). CONCLUSION Spherical markers can be identified from their phase saddles, enabling clear visualization, precise localization, and accurate quantification of their magnetic strength, in a wide range of clinically relevant pulse sequences and sampling strategies.
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Affiliation(s)
- Job G Bouwman
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Bram A Custers
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Chris J G Bakker
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Max A Viergever
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Peter R Seevinck
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
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McNabb E, Wong R, Noseworthy MD. Localizing implanted fiducial markers using undersampled co-RASOR MR imaging. Magn Reson Imaging 2017; 48:1-9. [PMID: 29229307 DOI: 10.1016/j.mri.2017.12.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 12/04/2017] [Indexed: 01/04/2023]
Abstract
The goal of this work was to use an undersampled, dual-plane centre-out radial sampling acquisition pulse sequence, with off-resonance reception, to localize fiducial markers with reduced acquisition time. Two iterative reconstruction techniques, conjugate gradient CG-SENSE and the variational penalty Total Generalized Variation (TGV), were investigated to minimize the undersampling artifacts in off-resonant radial imaging. Simulations of a field perturber were performed at sub-millimeter resolution and reconstructed to display signal pileups that can be radially compressed towards the geometric centre of the perturber for high contrast visualization, but contrast is non-recoverable as the echo time increases. A cylindrical platinum fiducial marker, placed in a phantom parallel and perpendicular to the B0-field was imaged with a short-TE half-echo readout. Contrast-to-Noise (CNR) between the signal of the fiducial its adjacent surrounding shell and half-maximum area were used to compare reconstruction methods and undersampling factors. For single slice acquisitions centred about the fiducial, each slice can be performed in as little as 2.8s. The total acquisition time to localize the fiducial marker in a phantom was reduced to 73s by undersampling (R=8) 37 axial and 15 coronal slices, effectively encoding 1.4s/slice. The noise present in undersampled images, for both scan planes and fiducial orientations, decreased significantly using TGV and CG-SENSE reconstructions, with TGV displaying better spatial resolution from reduced half-maximum area.
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Affiliation(s)
- Evan McNabb
- McMaster School of Biomedical Engineering, McMaster University, Hamilton, Canada
| | - Raimond Wong
- Juravinksi Cancer Centre, Hamilton, Ontario, Canada; Department of Oncology, McMaster University, Hamilton, Ontario, Canada; Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Michael D Noseworthy
- McMaster School of Biomedical Engineering, McMaster University, Hamilton, Canada; Imaging Research Centre, St. Joseph's Healthcare, Hamilton, Ontario, Canada; Department of Electrical and Computer Engineering, McMaster University, Hamilton, Ontario, Canada; Department of Radiology, McMaster University, Hamilton, Ontario, Canada.
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Maspero M, van den Berg CAT, Zijlstra F, Sikkes GG, de Boer HCJ, Meijer GJ, Kerkmeijer LGW, Viergever MA, Lagendijk JJW, Seevinck PR. Evaluation of an automatic MR-based gold fiducial marker localisation method for MR-only prostate radiotherapy. ACTA ACUST UNITED AC 2017; 62:7981-8002. [DOI: 10.1088/1361-6560/aa875f] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Magnitsky S, Zhang J, Idiyatullin D, Mohan G, Garwood M, Lane NE, Majumdar S. Positive contrast from cells labeled with iron oxide nanoparticles: Quantitation of imaging data. Magn Reson Med 2017; 78:1900-1910. [PMID: 28097749 DOI: 10.1002/mrm.26585] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 11/18/2016] [Accepted: 11/23/2016] [Indexed: 01/05/2023]
Abstract
PURPOSE Conventional T2 -weighted MRI produces a hypointense signal from iron-labeled cells, which renders quantification unfeasible. We tested a SWeep Imaging with Fourier Transformation (SWIFT) MRI pulse sequence to generate a quantifiable hyperintense signal from iron-labeled cells. METHODS Mesenchymal stem cells (MSCs) were labeled with different concentrations of iron oxide particles and examined for cell viability, proliferation, and differentiation. The SWIFT sequence was optimized to detect and quantify the amount of iron in the muscle tissue after injection of iron oxide solution and iron-labeled MSCs. RESULTS The incubation of MSCs with iron oxide and low concentration of poly-L-lysine mixture resulted in an internalization of up to 22 pg of iron per cell with no adverse effect on MSCs. Phantom experiments showed a dependence of SWIFT signal intensity on the excitation flip angle. The hyperintense signal from iron-labeled cells or solutions was detected, and an amount of the iron oxide in the tissue was quantified with the variable flip angle method. CONCLUSIONS The SWIFT sequence can produce a quantifiable hyperintense MRI signal from iron-labeled cells. The graft of 18 x 106 cells was detectable for 19 days after injection and the amount of iron was quantifiable. The proposed protocol simplifies the detection and provides a means to quantify cell numbers. Magn Reson Med 78:1900-1910, 2017. © 2017 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Sergey Magnitsky
- Musculoskeletal Quantitative Imaging Research, Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA
| | - Jinjin Zhang
- Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Djaudat Idiyatullin
- Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Geetha Mohan
- Center for Musculoskeletal Health, University of California at Davis School of Medicine, Sacramento, California, USA
| | - Michael Garwood
- Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Nancy E Lane
- Center for Musculoskeletal Health, University of California at Davis School of Medicine, Sacramento, California, USA
| | - Sharmila Majumdar
- Musculoskeletal Quantitative Imaging Research, Department of Radiology and Biomedical Imaging, University of California, San Francisco, California, USA
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Gimenez U, Lajous H, El Atifi M, Bidart M, Auboiroux V, Fries PH, Berger F, Lahrech H. In vivoquantification of magnetically labelled cells by MRI relaxometry. CONTRAST MEDIA & MOLECULAR IMAGING 2016; 11:535-543. [DOI: 10.1002/cmmi.1715] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 07/21/2016] [Accepted: 08/19/2016] [Indexed: 01/22/2023]
Affiliation(s)
- Ulysse Gimenez
- CLINATEC Translational Technology Lab INSERM U1205; CEA Grenoble France
| | - Hélène Lajous
- CLINATEC Translational Technology Lab INSERM U1205; CEA Grenoble France
| | - Michèle El Atifi
- CLINATEC Translational Technology Lab INSERM U1205; CEA Grenoble France
| | - Marie Bidart
- CLINATEC Translational Technology Lab INSERM U1205; CEA Grenoble France
| | | | | | - François Berger
- CLINATEC Translational Technology Lab INSERM U1205; CEA Grenoble France
| | - Hana Lahrech
- CLINATEC Translational Technology Lab INSERM U1205; CEA Grenoble France
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Delangre S, Vuong QL, Po C, Gallez B, Gossuin Y. Improvement of the Off-Resonance Saturation, an MRI sequence for positive contrast with SPM particles: Theoretical and experimental study. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 265:99-107. [PMID: 26894477 DOI: 10.1016/j.jmr.2016.02.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 02/02/2016] [Accepted: 02/04/2016] [Indexed: 06/05/2023]
Abstract
The SuperParaMagnetic particles (SPM particles) are used as contrast agents in MRI and produce negative contrast with conventional T2 or T2(∗)-weighted sequences. Unfortunately, the SPM particle detection on images acquired with such sequences is sometimes difficult because negative contrast can be created by artifacts such as air bubbles or calcification. To overcome this problem, new sequences as Off-Resonance Saturation (ORS) were developed to produce positive contrast with SPM particles. This work explores a new way to optimize the contrast generated by the ORS sequence by increasing the number of saturation pulses applied before the imaging sequence. This modified sequence is studied with numerical simulations and experiments on agarose gel phantoms. A theoretical model able to predict the contrast for different values of the sequence parameters is also developed. The results show that the contrast increases with the saturation pulses number with an optimal value of three saturation pulses in order to avoid artifacts and limit the Specific Absorption Rate (SAR) effect. The dependence of the contrast on the SPM particle concentration and sequence parameters is comparable to what was observed for the ORS sequence.
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Affiliation(s)
- S Delangre
- Biomedical Physics Unit, Université de Mons, Place du Parc 20, 7000 Mons, Belgium
| | - Q L Vuong
- Biomedical Physics Unit, Université de Mons, Place du Parc 20, 7000 Mons, Belgium
| | - C Po
- Biomedical Magnetic Resonance Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - B Gallez
- Biomedical Magnetic Resonance Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Y Gossuin
- Biomedical Physics Unit, Université de Mons, Place du Parc 20, 7000 Mons, Belgium.
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Quantification of susceptibility change at high-concentrated SPIO-labeled target by characteristic phase gradient recognition. Magn Reson Imaging 2015; 34:552-61. [PMID: 26592796 DOI: 10.1016/j.mri.2015.11.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Revised: 11/04/2015] [Accepted: 11/17/2015] [Indexed: 11/21/2022]
Abstract
Phase map cross-correlation detection and quantification may produce highlighted signal at superparamagnetic iron oxide nanoparticles, and distinguish them from other hypointensities. The method may quantify susceptibility change by performing least squares analysis between a theoretically generated magnetic field template and an experimentally scanned phase image. Because characteristic phase recognition requires the removal of phase wrap and phase background, additional steps of phase unwrapping and filtering may increase the chance of computing error and enlarge the inconsistence among algorithms. To solve problem, phase gradient cross-correlation and quantification method is developed by recognizing characteristic phase gradient pattern instead of phase image because phase gradient operation inherently includes unwrapping and filtering functions. However, few studies have mentioned the detectable limit of currently used phase gradient calculation algorithms. The limit may lead to an underestimation of large magnetic susceptibility change caused by high-concentrated iron accumulation. In this study, mathematical derivation points out the value of maximum detectable phase gradient calculated by differential chain algorithm in both spatial and Fourier domain. To break through the limit, a modified quantification method is proposed by using unwrapped forward differentiation for phase gradient generation. The method enlarges the detectable range of phase gradient measurement and avoids the underestimation of magnetic susceptibility. Simulation and phantom experiments were used to quantitatively compare different methods. In vivo application performs MRI scanning on nude mice implanted by iron-labeled human cancer cells. Results validate the limit of detectable phase gradient and the consequent susceptibility underestimation. Results also demonstrate the advantage of unwrapped forward differentiation compared with differential chain algorithms for susceptibility quantification at high-concentrated iron accumulation.
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Abstract
The use of magnetic resonance imaging (MRI) in radiotherapy (RT) planning is rapidly expanding. We review the wide range of image contrast mechanisms available to MRI and the way they are exploited for RT planning. However a number of challenges are also considered: the requirements that MR images are acquired in the RT treatment position, that they are geometrically accurate, that effects of patient motion during the scan are minimized, that tissue markers are clearly demonstrated, that an estimate of electron density can be obtained. These issues are discussed in detail, prior to the consideration of a number of specific clinical applications. This is followed by a brief discussion on the development of real-time MRI-guided RT.
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Affiliation(s)
- Maria A Schmidt
- Cancer Research UK Cancer Imaging Centre, Royal Marsden Hospital and the Institute of Cancer Research, Downs Road, Sutton, Surrey, SM2 5PT, UK
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Delangre S, Vuong QL, Henrard D, Po C, Gallez B, Gossuin Y. Bottom-up study of the MRI positive contrast created by the Off-Resonance Saturation sequence. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2015; 254:98-109. [PMID: 25863894 DOI: 10.1016/j.jmr.2015.02.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 02/12/2015] [Accepted: 02/24/2015] [Indexed: 06/04/2023]
Abstract
Superparamagnetic iron oxide nanoparticles (SPM particles) are used in MRI to highlight regions such as tumors through negative contrast. Unfortunately, sources as air bubbles or tissues interfaces also lead to negative contrast, which complicates the image interpretation. New MRI sequences creating positive contrast in the particle surrounding, such as the Off-Resonance Saturation sequence (ORS), have thus been developed. However, a theoretical study of the ORS sequence is still lacking, which hampers the optimization of this sequence. For this reason, this work provides a self-consistent analytical expression able to predict the dependence of the contrast on the sequence parameters and the SPM particles properties. This expression was validated by numerical simulations and experiments on agarose gel phantoms on a 11.7 T scanner system. It provides a fundamental understanding of the mechanisms leading to positive contrast, which could allow the improvement of the sequence for future in vivo applications. The influence of the SPM particle relaxivities, the SPM particle concentration, the echo time and the saturation pulse parameters on the contrast were investigated. The best contrast was achieved with SPM particles possessing the smallest transverse relaxivity, an optimal particle concentration and for low echo times.
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Affiliation(s)
- S Delangre
- Biomedical Physics Department, Université de Mons, Place du Parc 20, 7000 Mons, Belgium
| | - Q L Vuong
- Biomedical Physics Department, Université de Mons, Place du Parc 20, 7000 Mons, Belgium
| | - D Henrard
- Biomedical Physics Department, Université de Mons, Place du Parc 20, 7000 Mons, Belgium
| | - C Po
- Biomedical Magnetic Resonance Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - B Gallez
- Biomedical Magnetic Resonance Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, Brussels, Belgium
| | - Y Gossuin
- Biomedical Physics Department, Université de Mons, Place du Parc 20, 7000 Mons, Belgium.
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Delangre S, Vuong QL, Henrard D, Magat J, Po C, Gallez B, Gossuin Y. Theoretical and experimental study of ON-Resonance Saturation, an MRI sequence for positive contrast with superparamagnetic nanoparticles. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2015; 252:151-162. [PMID: 25700117 DOI: 10.1016/j.jmr.2015.01.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 01/13/2015] [Accepted: 01/14/2015] [Indexed: 06/04/2023]
Abstract
Superparamagnetic iron oxide nanoparticles (SPM particles) are widely used in MRI as negative contrast agents. Their detection is sometimes difficult because negative contrast can be caused by different artifacts. To overcome this problem, MRI protocols achieving positive contrast specific to SPM particles were developed such as the ON-Resonance Saturation (ONRS) sequence. The aim of the present work is to achieve a bottom-up study of the ONRS sequence by an understanding of the physical mechanisms leading to positive contrast. A complete theoretical modeling, a novel numerical simulation approach and experiments on agarose gel phantoms on a 11.7 T MRI system were carried out for this purpose. The influence of the particle properties and concentration - as well as the effect of the sequence parameters on the contrast - were investigated. It was observed that theory and experiments were in strong agreement. The tools developed in this work allowed to predict the parameters leading to the maximum contrast. For example, particles presenting a low transverse relaxivity can provide an interesting positive contrast after optimization of their concentration in the sample.
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Affiliation(s)
- S Delangre
- Biomedical Physics Department, University of Mons, 24, Avenue du Champ de Mars, 7000 Mons, Belgium
| | - Q L Vuong
- Biomedical Physics Department, University of Mons, 24, Avenue du Champ de Mars, 7000 Mons, Belgium
| | - D Henrard
- Biomedical Physics Department, University of Mons, 24, Avenue du Champ de Mars, 7000 Mons, Belgium
| | - J Magat
- Biomedical Magnetic Resonance Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, 73, Avenue E. Mounier, 1200 Brussels, Belgium
| | - C Po
- Biomedical Magnetic Resonance Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, 73, Avenue E. Mounier, 1200 Brussels, Belgium
| | - B Gallez
- Biomedical Magnetic Resonance Research Group, Louvain Drug Research Institute, Université Catholique de Louvain, 73, Avenue E. Mounier, 1200 Brussels, Belgium
| | - Y Gossuin
- Biomedical Physics Department, University of Mons, 24, Avenue du Champ de Mars, 7000 Mons, Belgium.
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Mulas G, Ferrauto G, Dastrù W, Anedda R, Aime S, Terreno E. Insights on the relaxation of liposomes encapsulating paramagnetic Ln-based complexes. Magn Reson Med 2014; 74:468-73. [DOI: 10.1002/mrm.25412] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 07/09/2014] [Accepted: 07/24/2014] [Indexed: 12/22/2022]
Affiliation(s)
- Gilberto Mulas
- Department of Molecular Biotechnology and Health Sciences; University of Torino; Torino Italy
- Porto Conte Ricerche Srl; Tramariglio Alghero (SS) Italy
| | - Giuseppe Ferrauto
- Department of Molecular Biotechnology and Health Sciences; University of Torino; Torino Italy
| | - Walter Dastrù
- Department of Molecular Biotechnology and Health Sciences; University of Torino; Torino Italy
| | - Roberto Anedda
- Porto Conte Ricerche Srl; Tramariglio Alghero (SS) Italy
| | - Silvio Aime
- Department of Molecular Biotechnology and Health Sciences; University of Torino; Torino Italy
- Center for Molecular & Preclinical Imaging, Department of Molecular Biotechnology and Health Sciences; University of Torino; Torino Italy
| | - Enzo Terreno
- Department of Molecular Biotechnology and Health Sciences; University of Torino; Torino Italy
- Center for Molecular & Preclinical Imaging, Department of Molecular Biotechnology and Health Sciences; University of Torino; Torino Italy
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