1
|
Han H, Shang Y. Fabrication of a 25.2 T NMR magnet for an extreme condition user facility in China. Natl Sci Rev 2024; 11:nwae165. [PMID: 38883305 PMCID: PMC11177881 DOI: 10.1093/nsr/nwae165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 03/27/2024] [Accepted: 04/22/2024] [Indexed: 06/18/2024] Open
Abstract
This article highlights a research study on the fabrication of a 25.2 T ultra-high field NMR magnet for an extreme condition user facility in China.
Collapse
Affiliation(s)
- Hui Han
- MRI Research Institute, Department of Radiology, Weill Medical College of Cornell University, USA
| | - Yun Shang
- MRI Research Institute, Department of Radiology, Weill Medical College of Cornell University, USA
| |
Collapse
|
2
|
Seghier ML. 7 T and beyond: toward a synergy between fMRI-based presurgical mapping at ultrahigh magnetic fields, AI, and robotic neurosurgery. Eur Radiol Exp 2024; 8:73. [PMID: 38945979 PMCID: PMC11214939 DOI: 10.1186/s41747-024-00472-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Accepted: 04/22/2024] [Indexed: 07/02/2024] Open
Abstract
Presurgical evaluation with functional magnetic resonance imaging (fMRI) can reduce postsurgical morbidity. Here, we discuss presurgical fMRI mapping at ultra-high magnetic fields (UHF), i.e., ≥ 7 T, in the light of the current growing interest in artificial intelligence (AI) and robot-assisted neurosurgery. The potential of submillimetre fMRI mapping can help better appreciate uncertainty on resection margins, though geometric distortions at UHF might lessen the accuracy of fMRI maps. A useful trade-off for UHF fMRI is to collect data with 1-mm isotropic resolution to ensure high sensitivity and subsequently a low risk of false negatives. Scanning at UHF might yield a revival interest in slow event-related fMRI, thereby offering a richer depiction of the dynamics of fMRI responses. The potential applications of AI concern denoising and artefact removal, generation of super-resolution fMRI maps, and accurate fusion or coregistration between anatomical and fMRI maps. The latter can benefit from the use of T1-weighted echo-planar imaging for better visualization of brain activations. Such AI-augmented fMRI maps would provide high-quality input data to robotic surgery systems, thereby improving the accuracy and reliability of robot-assisted neurosurgery. Ultimately, the advancement in fMRI at UHF would promote clinically useful synergies between fMRI, AI, and robotic neurosurgery.Relevance statement This review highlights the potential synergies between fMRI at UHF, AI, and robotic neurosurgery in improving the accuracy and reliability of fMRI-based presurgical mapping.Key points• Presurgical fMRI mapping at UHF improves spatial resolution and sensitivity.• Slow event-related designs offer a richer depiction of fMRI responses dynamics.• AI can support denoising, artefact removal, and generation of super-resolution fMRI maps.• AI-augmented fMRI maps can provide high-quality input data to robotic surgery systems.
Collapse
Affiliation(s)
- Mohamed L Seghier
- Department of Biomedical Engineering and Biotechnology, Khalifa University of Science and Technology, Abu Dhabi, UAE.
- Healtcare Engineering Innovation Center (HEIC), Khalifa University of Science and Technology, Abu Dhabi, UAE.
| |
Collapse
|
3
|
Zhou XC, Chen LH, Wu S, Wang KZ, Wei ZC, Li T, Huang YS, Hua ZH, Xia Q, Lv ZZ, Lv LJ. Brain effect mechanism of lever positioning manipulation on LDH analgesia based on multimodal MRI: a study protocol. BMC Complement Med Ther 2024; 24:246. [PMID: 38915038 PMCID: PMC11194935 DOI: 10.1186/s12906-024-04549-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Accepted: 06/11/2024] [Indexed: 06/26/2024] Open
Abstract
INTRODUCTION The clinical symptoms of Lumbar Disc Herniation (LDH) can be effectively ameliorated through Lever Positioning Manipulation (LPM), which is closely linked to the brain's pain-regulating mechanisms. Magnetic Resonance Imaging (MRI) offers an objective and visual means to study how the brain orchestrates the characteristics of analgesic effects. From the perspective of multimodal MRI, we applied functional MRI (fMRI) and Magnetic Resonance Spectrum (MRS) techniques to comprehensively evaluate the characteristics of the effects of LPM on the brain region of LDH from the aspects of brain structure, brain function and brain metabolism. This multimodal MRI technique provides a biological basis for the clinical application of LPM in LDH. METHODS AND ANALYSIS A total of 60 LDH patients and 30 healthy controls, matched by gender, age, and years of education, will be enrolled in this study. The LDH patients will be divided into two groups (Group 1, n = 30; Group 2, n = 30) using a random number table method. Group 1 will receive LPM treatment once every two days, for a total of 12 times over 4 weeks. Group 2 will receive sham LPM treatment during the same period as Group 1. All 30 healthy controls will be divided into Group 3. Multimodal MRI will be performed on Group 1 and Group 2 at three time points (TPs): before LPM (TP1), after one LPM session (TP2), and after a full course of LPM treatment. The healthy controls (Group 3) will not undergo LPM and will be subject to only a single multimodal MRI scan. Participants in both Group 1 and Group 2 will be required to complete clinical questionnaires. These assessments will focus on pain intensity and functional disorders, using the Visual Analog Scale (VAS) and the Japanese Orthopaedic Association (JOA) scoring systems, respectively. DISCUSSION The purpose of this study is to investigate the multimodal brain response characteristics of LDH patients after treatment with LPM, with the goal of providing a biological basis for clinical applications. TRIAL REGISTRATION NUMBER https://clinicaltrials.gov/ct2/show/NCT05613179 , identifier: NCT05613179.
Collapse
Affiliation(s)
- Xing-Chen Zhou
- The Third Affiliated Hospital of Zhejiang, University of Traditional Chinese Medicine, Hangzhou, Zhejiang, China
- The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
- Research Institute of Tuina (Spinal Disease), Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Long-Hao Chen
- The Third Affiliated Hospital of Zhejiang, University of Traditional Chinese Medicine, Hangzhou, Zhejiang, China
- The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
- Research Institute of Tuina (Spinal Disease), Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Shuang Wu
- The Third Affiliated Hospital of Zhejiang, University of Traditional Chinese Medicine, Hangzhou, Zhejiang, China
- The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Kai-Zheng Wang
- The Third Affiliated Hospital of Zhejiang, University of Traditional Chinese Medicine, Hangzhou, Zhejiang, China
- The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
- Research Institute of Tuina (Spinal Disease), Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Zi-Cheng Wei
- The Third Affiliated Hospital of Zhejiang, University of Traditional Chinese Medicine, Hangzhou, Zhejiang, China
- The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Tao Li
- The Third Affiliated Hospital of Zhejiang, University of Traditional Chinese Medicine, Hangzhou, Zhejiang, China
- The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Yuan-Shen Huang
- The Third Affiliated Hospital of Zhejiang, University of Traditional Chinese Medicine, Hangzhou, Zhejiang, China
- The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
- Research Institute of Tuina (Spinal Disease), Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Zi-Han Hua
- The Third Affiliated Hospital of Zhejiang, University of Traditional Chinese Medicine, Hangzhou, Zhejiang, China
- The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Qiong Xia
- The Third Affiliated Hospital of Zhejiang, University of Traditional Chinese Medicine, Hangzhou, Zhejiang, China
- The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Zhi-Zhen Lv
- The Third Affiliated Hospital of Zhejiang, University of Traditional Chinese Medicine, Hangzhou, Zhejiang, China.
- The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China.
| | - Li-Jiang Lv
- The Third Affiliated Hospital of Zhejiang, University of Traditional Chinese Medicine, Hangzhou, Zhejiang, China.
- The Third School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China.
| |
Collapse
|
4
|
Versteeg E, Nam KM, Klomp DWJ, Bhogal AA, Siero JCW, Wijnen JP. A silent echo-planar spectroscopic imaging readout with high spectral bandwidth MRSI using an ultrasonic gradient axis. Magn Reson Med 2024; 91:2247-2256. [PMID: 38205917 DOI: 10.1002/mrm.30008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 12/18/2023] [Accepted: 12/21/2023] [Indexed: 01/12/2024]
Abstract
PURPOSE We present a novel silent echo-planar spectroscopic imaging (EPSI) readout, which uses an ultrasonic gradient insert to accelerate MRSI while producing a high spectral bandwidth (20 kHz) and a low sound level. METHODS The ultrasonic gradient insert consisted of a single-axis (z-direction) plug-and-play gradient coil, powered by an audio amplifier, and produced 40 mT/m at 20 kHz. The silent EPSI readout was implemented in a phase-encoded MRSI acquisition. Here, the additional spatial encoding provided by this silent EPSI readout was used to reduce the number of phase-encoding steps. Spectroscopic acquisitions using phase-encoded MRSI, a conventional EPSI-readout, and the silent EPSI readout were performed on a phantom containing metabolites with resonance frequencies in the ppm range of brain metabolites (0-4 ppm). These acquisitions were used to determine sound levels, showcase the high spectral bandwidth of the silent EPSI readout, and determine the SNR efficiency and the scan efficiency. RESULTS The silent EPSI readout featured a 19-dB lower sound level than a conventional EPSI readout while featuring a high spectral bandwidth of 20 kHz without spectral ghosting artifacts. Compared with phase-encoded MRSI, the silent EPSI readout provided a 4.5-fold reduction in scan time. In addition, the scan efficiency of the silent EPSI readout was higher (82.5% vs. 51.5%) than the conventional EPSI readout. CONCLUSIONS We have for the first time demonstrated a silent spectroscopic imaging readout with a high spectral bandwidth and low sound level. This sound reduction provided by the silent readout is expected to have applications in sound-sensitive patient groups, whereas the high spectral bandwidth could benefit ultrahigh-field MR systems.
Collapse
Affiliation(s)
- Edwin Versteeg
- Center for Image Sciences, Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Kyung Min Nam
- Center for Image Sciences, Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Dennis W J Klomp
- Center for Image Sciences, Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Alex A Bhogal
- Center for Image Sciences, Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jeroen C W Siero
- Center for Image Sciences, Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
- Spinoza Centre for Neuroimaging, Amsterdam, Netherlands
| | - Jannie P Wijnen
- Center for Image Sciences, Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| |
Collapse
|
5
|
Bouisset N, Nissi J, Laakso I, Reynolds RF, Legros A. Is activation of the vestibular system by electromagnetic induction a possibility in an MRI context? Bioelectromagnetics 2024; 45:171-183. [PMID: 38348647 DOI: 10.1002/bem.22497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Revised: 11/21/2023] [Accepted: 12/16/2023] [Indexed: 04/17/2024]
Abstract
In recent years, an increasing number of studies have discussed the mechanisms of vestibular activation in strong magnetic field settings such as occur in a magnetic resonance imaging scanner environment. Amid the different hypotheses, the Lorentz force explanation currently stands out as the most plausible mechanism, as evidenced by activation of the vestibulo-ocular reflex. Other hypotheses have largely been discarded. Nonetheless, both human data and computational modeling suggest that electromagnetic induction could be a valid mechanism which may coexist alongside the Lorentz force. To further investigate the induction hypothesis, we provide, herein, a first of its kind dosimetric analysis to estimate the induced electric fields at the vestibular system and compare them with what galvanic vestibular stimulation would generate. We found that electric fields strengths from induction match galvanic vestibular stimulation strengths generating vestibular responses. This review examines the evidence in support of electromagnetic induction of vestibular responses, and whether movement-induced time-varying magnetic fields should be further considered and investigated.
Collapse
Affiliation(s)
- Nicolas Bouisset
- Human Threshold Research Group, Lawson Health Research Institute, London, Ontario, Canada
- School of Kinesiology, Western University, London, Ontario, Canada
| | - Janita Nissi
- Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland
| | - Ilkka Laakso
- Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland
| | - Raymond F Reynolds
- School of Sport, Exercise & Rehabilitation Sciences, University of Birmingham, Birmingham, UK
| | - Alexandre Legros
- Human Threshold Research Group, Lawson Health Research Institute, London, Ontario, Canada
- School of Kinesiology, Western University, London, Ontario, Canada
- EuroMov Digital Health in Motion, Univ Montpellier, IMT Mines Ales, Montpellier, France
- Departments of Medical Biophysics and Medical Imaging Western University, London, Ontario, Canada
- Eurostim, Montpellier, France
| |
Collapse
|
6
|
Yang CY, Meng Z, Yang K, He Z, Hou Z, Yang J, Lu J, Cao Z, Yang S, Chai Y, Zhao H, Zhao L, Sun X, Wang G, Wang X. External magnetic field non-invasively stimulates spinal cord regeneration in rat via a magnetic-responsive aligned fibrin hydrogel. Biofabrication 2023; 15:035022. [PMID: 37279745 DOI: 10.1088/1758-5090/acdbec] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Accepted: 06/06/2023] [Indexed: 06/08/2023]
Abstract
Magnetic stimulation is becoming an attractive approach to promote neuroprotection, neurogenesis, axonal regeneration, and functional recovery in both the central nervous system and peripheral nervous system disorders owing to its painless, non-invasive, and deep penetration characteristics. Here, a magnetic-responsive aligned fibrin hydrogel (MAFG) was developed to import and amplify the extrinsic magnetic field (MF) locally to stimulate spinal cord regeneration in combination with the beneficial topographical and biochemical cues of aligned fibrin hydrogel (AFG). Magnetic nanoparticles (MNPs) were embedded uniformly in AFG during electrospinning to endow it magnetic-responsive feature, with saturation magnetization of 21.79 emu g-1. It is found that the MNPs under the MF could enhance cell proliferation and neurotrophin secretion of PC12 cellsin vitro. The MAFG that was implanted into a rat with 2 mm complete transected spinal cord injury (SCI) effectively enhanced neural regeneration and angiogenesis in the lesion area, thus leading to significant recovery of motor function under the MF (MAFG@MF). This study suggests a new multimodal tissue engineering strategy based on multifunctional biomaterials that deliver multimodal regulatory signals with the integration of aligned topography, biochemical cues, and extrinsic MF stimulation for spinal cord regeneration following severe SCI.
Collapse
Affiliation(s)
- Chun-Yi Yang
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Zhe Meng
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
- Department of Neurosurgery, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing 102218, People's Republic of China
| | - Kaiyuan Yang
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
- Department of Neurosurgery, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing 102218, People's Republic of China
| | - Zhijun He
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
- Department of Neurosurgery, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing 102218, People's Republic of China
| | - Zhaohui Hou
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Jia Yang
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Jingsong Lu
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Zheng Cao
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Shuhui Yang
- School of Materials Science and Engineering, Zhejiang-Mauritius Joint Research Center for Biomaterials and Tissue Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, People's Republic of China
| | - Yi Chai
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - He Zhao
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Lingyun Zhao
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Xiaodan Sun
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Guihuai Wang
- Department of Neurosurgery, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing 102218, People's Republic of China
| | - Xiumei Wang
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| |
Collapse
|
7
|
Schmidt R, Keban E, Bollmann S, Wiggins CJ, Niendorf T. Scaling the mountains: what lies above 7 Tesla magnetic resonance? MAGMA (NEW YORK, N.Y.) 2023; 36:151-157. [PMID: 37072540 PMCID: PMC10140119 DOI: 10.1007/s10334-023-01087-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/27/2023] [Indexed: 04/20/2023]
Affiliation(s)
- Rita Schmidt
- Department of Brain Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Elena Keban
- Department of Diagnostic, Interventional and Pediatric Radiology, Inselspital, University of Bern, Bern, Switzerland
| | - Saskia Bollmann
- School of Information Technology and Electrical Engineering, Faculty of Engineering, Architecture and Information Technology, The University of Queensland, Brisbane, Australia
| | - Christopher J Wiggins
- Imaging Core Facility, Institute for Neurology and Medicine, Forschungszentrum Julich, Julich, Germany
| | - Thoralf Niendorf
- Berlin Ultrahigh Field Facility, Max-Delbrueck Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany.
| |
Collapse
|
8
|
Bates S, Dumoulin SO, Folkers PJM, Formisano E, Goebel R, Haghnejad A, Helmich RC, Klomp D, van der Kolk AG, Li Y, Nederveen A, Norris DG, Petridou N, Roell S, Scheenen TWJ, Schoonheim MM, Voogt I, Webb A. A vision of 14 T MR for fundamental and clinical science. MAGMA (NEW YORK, N.Y.) 2023; 36:211-225. [PMID: 37036574 PMCID: PMC10088620 DOI: 10.1007/s10334-023-01081-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 03/20/2023] [Accepted: 03/21/2023] [Indexed: 04/11/2023]
Abstract
OBJECTIVE We outline our vision for a 14 Tesla MR system. This comprises a novel whole-body magnet design utilizing high temperature superconductor; a console and associated electronic equipment; an optimized radiofrequency coil setup for proton measurement in the brain, which also has a local shim capability; and a high-performance gradient set. RESEARCH FIELDS The 14 Tesla system can be considered a 'mesocope': a device capable of measuring on biologically relevant scales. In neuroscience the increased spatial resolution will anatomically resolve all layers of the cortex, cerebellum, subcortical structures, and inner nuclei. Spectroscopic imaging will simultaneously measure excitatory and inhibitory activity, characterizing the excitation/inhibition balance of neural circuits. In medical research (including brain disorders) we will visualize fine-grained patterns of structural abnormalities and relate these changes to functional and molecular changes. The significantly increased spectral resolution will make it possible to detect (dynamic changes in) individual metabolites associated with pathological pathways including molecular interactions and dynamic disease processes. CONCLUSIONS The 14 Tesla system will offer new perspectives in neuroscience and fundamental research. We anticipate that this initiative will usher in a new era of ultra-high-field MR.
Collapse
Affiliation(s)
- Steve Bates
- Tesla Engineering Ltd., Water Lane, Storrington, West Sussex, RH20 3EA, UK
| | - Serge O Dumoulin
- Spinoza Centre for Neuroimaging, Amsterdam, The Netherlands
- Computational Cognitive Neuroscience and Neuroimaging, Netherlands Institute for Neuroscience, Amsterdam, The Netherlands
- Experimental and Applied Psychology, Vrije University Amsterdam, Amsterdam, The Netherlands
- Experimental Psychology, Utrecht University, Utrecht, The Netherlands
| | | | - Elia Formisano
- Department of Cognitive Neuroscience, Maastricht University, Maastricht, The Netherlands
- Maastricht Brain Imaging Centre (MBIC), Maastricht University, Maastricht, The Netherlands
| | - Rainer Goebel
- Department of Cognitive Neuroscience, Maastricht University, Maastricht, The Netherlands
- Maastricht Brain Imaging Centre (MBIC), Maastricht University, Maastricht, The Netherlands
| | | | - Rick C Helmich
- Donders Institute for Brain, Cognition and Behaviour, Centre for Cognitive Neuroimaging, Radboud University, Nijmegen, The Netherlands
- Department of Neurology, Center of Expertise for Parkinson and Movement Disorders, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Dennis Klomp
- Radiology Department, Center for Image Sciences, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Anja G van der Kolk
- Department of Medical Imaging, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Yi Li
- Independent Researcher, Magdeburg, Germany
| | - Aart Nederveen
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, Amsterdam Cardiovascular Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - David G Norris
- Donders Institute for Brain, Cognition and Behaviour, Centre for Cognitive Neuroimaging, Radboud University, Nijmegen, The Netherlands.
- Erwin L. Hahn Institute for Magnetic Resonance Imaging UNESCO World Cultural Heritage Zollverein, Kokereiallee 7, Building C84, 45141, Essen, Germany.
- Department of Clinical Neurophysiology (CNPH), Faculty Science and Technology, University of Twente, Enschede, The Netherlands.
| | - Natalia Petridou
- Radiology Department, Center for Image Sciences, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Stefan Roell
- Neoscan Solutions GmbH, Joseph-von-Fraunhofer-Str. 6, 39106, Magdeburg, Germany
| | - Tom W J Scheenen
- Department of Medical Imaging, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Menno M Schoonheim
- Department of Anatomy and Neurosciences, MS Center Amsterdam, Amsterdam Neuroscience, Amsterdam UMC, Vrije Universiteit Amsterdam, Location VUmc, P.O. Box 7057, 1007 MB, Amsterdam, The Netherlands
| | - Ingmar Voogt
- Wavetronica, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Andrew Webb
- Department of Radiology, C.J. Gorter MRI Centre, Leiden University Medical Center, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| |
Collapse
|
9
|
Nurzed B, Kuehne A, Aigner CS, Schmitter S, Niendorf T, Eigentler TW. Radiofrequency antenna concepts for human cardiac MR at 14.0 T. MAGMA (NEW YORK, N.Y.) 2023; 36:257-277. [PMID: 36920549 PMCID: PMC10140016 DOI: 10.1007/s10334-023-01075-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 02/23/2023] [Accepted: 02/27/2023] [Indexed: 04/28/2023]
Abstract
OBJECTIVE To examine the feasibility of human cardiac MR (CMR) at 14.0 T using high-density radiofrequency (RF) dipole transceiver arrays in conjunction with static and dynamic parallel transmission (pTx). MATERIALS AND METHODS RF arrays comprised of self-grounded bow-tie (SGBT) antennas, bow-tie (BT) antennas, or fractionated dipole (FD) antennas were used in this simulation study. Static and dynamic pTx were applied to enhance transmission field (B1+) uniformity and efficiency in the heart of the human voxel model. B1+ distribution and maximum specific absorption rate averaged over 10 g tissue (SAR10g) were examined at 7.0 T and 14.0 T. RESULTS At 14.0 T static pTx revealed a minimum B1+ROI efficiency of 0.91 μT/√kW (SGBT), 0.73 μT/√kW (BT), and 0.56 μT/√kW (FD) and maximum SAR10g of 4.24 W/kg, 1.45 W/kg, and 2.04 W/kg. Dynamic pTx with 8 kT points indicate a balance between B1+ROI homogeneity (coefficient of variation < 14%) and efficiency (minimum B1+ROI > 1.11 µT/√kW) at 14.0 T with a maximum SAR10g < 5.25 W/kg. DISCUSSION MRI of the human heart at 14.0 T is feasible from an electrodynamic and theoretical standpoint, provided that multi-channel high-density antennas are arranged accordingly. These findings provide a technical foundation for further explorations into CMR at 14.0 T.
Collapse
Affiliation(s)
- Bilguun Nurzed
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin Ultrahigh Field Facility (B.U.F.F.), Robert Rössle Strasse 10, 13125, Berlin, Germany
| | | | | | | | - Thoralf Niendorf
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin Ultrahigh Field Facility (B.U.F.F.), Robert Rössle Strasse 10, 13125, Berlin, Germany.
- MRI.TOOLS GmbH, Berlin, Germany.
- Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany.
| | - Thomas Wilhelm Eigentler
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin Ultrahigh Field Facility (B.U.F.F.), Robert Rössle Strasse 10, 13125, Berlin, Germany
- Chair of Medical Engineering, Technische Universität Berlin, Berlin, Germany
| |
Collapse
|
10
|
Boulant N, Quettier L. Commissioning of the Iseult CEA 11.7 T whole-body MRI: current status, gradient-magnet interaction tests and first imaging experience. MAGMA (NEW YORK, N.Y.) 2023; 36:175-189. [PMID: 36715884 PMCID: PMC10140097 DOI: 10.1007/s10334-023-01063-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 01/09/2023] [Accepted: 01/14/2023] [Indexed: 04/28/2023]
Abstract
OBJECTIVES The Iseult MRI is an actively shielded whole-body magnet providing a homogeneous and stable magnetic field of 11.7 T. After nearly 20 years of research and development, the magnet successfully reached its target field strength for the first time in 2019. This article reviews its commissioning status, the gradient-magnet interaction test results and first imaging experience. MATERIALS AND METHODS Vibration, acoustics, power deposition in the He bath, and field monitoring measurements were carried out. Magnet safety system was tested against outer magnetic perturbations, and calibrated to define a safe operation of the gradient coil. First measurements using parallel transmission were also performed on an ex-vivo brain to mitigate the RF field inhomogeneity effect. RESULTS Acoustics measurements show promising results with sound pressure levels slightly above the enforced limits only at certain frequency intervals. Vibrations of the gradient coil revealed a linear trend with the B0 field only in the worst case. Field monitoring revealed some resonances at some frequencies that are still under investigation. DISCUSSION Gradient-magnet interaction tests at up to 11.7 T are concluded. The scanner is now kept permanently at field and the final calibrations are on-going to pave the road towards the first acquisitions on volunteers.
Collapse
Affiliation(s)
- Nicolas Boulant
- Université Paris-Saclay, CEA, CNRS, BAOBAB, NeuroSpin, Gif Sur Yvette, France.
| | - Lionel Quettier
- Université Paris-Saclay, CEA, Irfu, Département des Accélérateurs, de la Cryogénie et du Magnétisme, Gif Sur Yvette, France
| |
Collapse
|
11
|
Liu Y, Wang Q, Liu F. A hybrid FDTD/MoM algorithm with a conformal Huygens' equivalent surface for MRI RF coil design and analysis. Magn Reson Imaging 2023; 102:1-8. [PMID: 36963640 DOI: 10.1016/j.mri.2023.03.013] [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: 11/03/2022] [Revised: 03/19/2023] [Accepted: 03/21/2023] [Indexed: 03/26/2023]
Abstract
Accurate design and analysis of radiofrequency (RF) coils are crucial for ultra-high field (UHF) magnetic resonance imaging (MRI) applications. To improve the numerical accuracy of electromagnetic (EM) simulations, we propose a hybrid finite difference time domain (FDTD)/method of moments (MoM) method. Unlike conventional cuboid-like Huygens' equivalent surfaces (HES), we proposed to use a conformal HES to interface the EM data of the FDTD and MoM zone. The shape and size of the conformal surface can be adjusted to fit different RF coil models, thus broadening the application range of the hybrid FDTD/MoM method. Two numerical models: an 8-channel ellipse array, and an 8-channel bent dipole array, are simulated and compared with the conventional HES counterpart. Numerical results demonstrate the capability of the conformal HES method in the analysis of RF coils.
Collapse
Affiliation(s)
- Yang Liu
- Key Laboratory of Applied Superconductivity, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China; School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qiuliang Wang
- Key Laboratory of Applied Superconductivity, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China; School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Feng Liu
- School of Information Technology and Electrical Engineering, The University of Queensland, St. Lucia, Brisbane, Qld 4072, Australia
| |
Collapse
|
12
|
Li A, Luo X, Chen D, Li L, Lin H, Gao J. Small Molecule Probes for 19F Magnetic Resonance Imaging. Anal Chem 2023; 95:70-82. [PMID: 36625117 DOI: 10.1021/acs.analchem.2c04539] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Ao Li
- The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Fujian Provincial Key Laboratory of Chemical Biology, and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen361005, China
| | - Xiangjie Luo
- The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Fujian Provincial Key Laboratory of Chemical Biology, and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen361005, China
| | - Dongxia Chen
- The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Fujian Provincial Key Laboratory of Chemical Biology, and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen361005, China
| | - Lingxuan Li
- The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Fujian Provincial Key Laboratory of Chemical Biology, and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen361005, China
| | - Hongyu Lin
- The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Fujian Provincial Key Laboratory of Chemical Biology, and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen361005, China
| | - Jinhao Gao
- The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Fujian Provincial Key Laboratory of Chemical Biology, and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen361005, China
| |
Collapse
|
13
|
Streckenbach F, Jäschke M, Jahns N, Langner I, König J, Wree A, Stahnke T, Stachs O, Frank M, Langner S, Lindner T. MR
microscopy of the developing upper extremity of the chicken in ovo using 7 Tesla
MRI. Anat Histol Embryol 2022; 52:356-362. [PMID: 36461880 DOI: 10.1111/ahe.12894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 11/25/2022] [Indexed: 12/04/2022]
Abstract
MR microscopy (MRM) is known as ultra-high-field (UHF) magnetic resonance imaging with an in-plane spatial resolution of <100 μm, yields highly resolved non-invasive anatomical imaging and allows longitudinal assessment of embryonic avian development. The aim of the present study was to evaluate the feasibility of in vivo anatomical MRI assessment of the developing upper extremity of the chicken. Thirty-eight fertilized chicken eggs were examined at 7 Tesla acquiring high-resolution T2-weighted images with an in-plane resolution of 74 × 74 μm. To reduce motion artefacts, the eggs were moderately cooled before and during MRI. Development of the upper extremity was anatomically and quantitatively assessed. Chondrification and ossification on MRI were correlated with histological examination. MRM allowed the identification of the embryo from stage D5 onwards. First chondrification of the upper extremity was visible at stage D7, and the differentiation of the forearm was possible from stage D9 throughout the developmental period with excellent correlation to histology. MRM also allowed the differentiation between cortical and medullary bone as well as the detection of chondrified areas. UHF MRM allows the in vivo and in ovo evaluation of the upper limb during embryonic development and provides non-invasive longitudinal anatomical information. This technique allows longitudinal studies of the same embryo during the developmental period and may therefore provide further insights into the development of the upper extremity. With improved coil technique and increasing availability of UHF MR systems, there is great potential regarding several research topics in experimental musculoskeletal radiology.
Collapse
Affiliation(s)
- Felix Streckenbach
- Institute for Diagnostic and Interventional Radiology, Pediatric and Neuroradiology Rostock University Medical Center Rostock Germany
| | - Malte Jäschke
- Institute for Diagnostic and Interventional Radiology, Pediatric and Neuroradiology Rostock University Medical Center Rostock Germany
| | - Nora Jahns
- Institute for Diagnostic Radiology and Neuroradiology University Medicine Greifswald Greifswald Germany
| | - Inga Langner
- Department of Orthopedics and Orthopaedic Surgery University Medicine Greifswald Greifswald Germany
| | - Julia König
- Department of Anesthesia and Intensive Care University Hospital Rostock Rostock Germany
| | - Andreas Wree
- Institute of Anatomy, Rostock University Medical Center Rostock Germany
| | - Thomas Stahnke
- Department of Ophthalmology Rostock University Medical Center Rostock Germany
- Institute for Implant Technology and Biomaterials‐IIB E.V Associated Institute of the University of Rostock Warnemuende Germany
| | - Oliver Stachs
- Department of Ophthalmology Rostock University Medical Center Rostock Germany
| | - Marcus Frank
- Medical Biology and Electron Microscopy Center Rostock University Medical Center Rostock Germany
- Department Life, Light & Matter University of Rostock Rostock Germany
| | - Sönke Langner
- Institute for Diagnostic and Interventional Radiology, Pediatric and Neuroradiology Rostock University Medical Center Rostock Germany
| | - Tobias Lindner
- Institute for Diagnostic and Interventional Radiology, Pediatric and Neuroradiology Rostock University Medical Center Rostock Germany
- Core Facility Multimodal Small Animal Imaging Rostock University Medical Center Rostock Germany
| |
Collapse
|
14
|
Nian R, Gao M, Zhang S, Yu J, Gholipour A, Kong S, Wang R, Sui Y, Velasco-Annis C, Tomas-Fernandez X, Li Q, Lv H, Qian Y, Warfield SK. Toward evaluation of multiresolution cortical thickness estimation with FreeSurfer, MaCRUISE, and BrainSuite. Cereb Cortex 2022; 33:5082-5096. [PMID: 36288912 DOI: 10.1093/cercor/bhac401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 09/09/2022] [Accepted: 09/11/2022] [Indexed: 11/12/2022] Open
Abstract
Abstract
Advances in Magnetic Resonance Imaging hardware and methodologies allow for promoting the cortical morphometry with submillimeter spatial resolution. In this paper, we generated 3D self-enhanced high-resolution (HR) MRI imaging, by adapting 1 deep learning architecture, and 3 standard pipelines, FreeSurfer, MaCRUISE, and BrainSuite, have been collectively employed to evaluate the cortical thickness. We systematically investigated the differences in cortical thickness estimation for MRI sequences at multiresolution homologously originated from the native image. It has been revealed that there systematically exhibited the preferences in determining both inner and outer cortical surfaces at higher resolution, yielding most deeper cortical surface placements toward GM/WM or GM/CSF boundaries, which directs a consistent reduction tendency of mean cortical thickness estimation; on the contrary, the lower resolution data will most probably provide a more coarse and rough evaluation in cortical surface reconstruction, resulting in a relatively thicker estimation. Although the differences of cortical thickness estimation at the diverse spatial resolution varied with one another, almost all led to roughly one-sixth to one-fifth significant reduction across the entire brain at the HR, independent to the pipelines we applied, which emphasizes on generally coherent improved accuracy in a data-independent manner and endeavors to cost-efficiency with quantitative opportunities.
Collapse
Affiliation(s)
- Rui Nian
- School of Electronic Engineering, Ocean University of China, 238 Songling Road, Qingdao, China
- Harvard Medical School, 25 Shattuck Street, Boston, MA, United States
- Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, United States
| | - Mingshan Gao
- Citigroup Services and Technology Limited, 1000 Chenhi Road, Shanghai, China
| | | | - Junjie Yu
- School of Electronic Engineering, Ocean University of China, 238 Songling Road, Qingdao, China
| | - Ali Gholipour
- Harvard Medical School, 25 Shattuck Street, Boston, MA, United States
- Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, United States
| | - Shuang Kong
- School of Electronic Engineering, Ocean University of China, 238 Songling Road, Qingdao, China
| | - Ruirui Wang
- School of Electronic Engineering, Ocean University of China, 238 Songling Road, Qingdao, China
| | - Yao Sui
- Harvard Medical School, 25 Shattuck Street, Boston, MA, United States
- Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, United States
| | - Clemente Velasco-Annis
- Harvard Medical School, 25 Shattuck Street, Boston, MA, United States
- Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, United States
| | - Xavier Tomas-Fernandez
- Harvard Medical School, 25 Shattuck Street, Boston, MA, United States
- Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, United States
| | - Qiuying Li
- School of Electronic Engineering, Ocean University of China, 238 Songling Road, Qingdao, China
| | - Hangyu Lv
- School of Electronic Engineering, Ocean University of China, 238 Songling Road, Qingdao, China
| | - Yuqi Qian
- School of Electronic Engineering, Ocean University of China, 238 Songling Road, Qingdao, China
| | - Simon K Warfield
- Harvard Medical School, 25 Shattuck Street, Boston, MA, United States
- Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, United States
| |
Collapse
|
15
|
Rosenberg JT, Grant SC, Topgaard D. Nonparametric 5D D-R 2 distribution imaging with single-shot EPI at 21.1 T: Initial results for in vivo rat brain. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2022; 341:107256. [PMID: 35753184 PMCID: PMC9339475 DOI: 10.1016/j.jmr.2022.107256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 05/27/2022] [Accepted: 06/10/2022] [Indexed: 06/15/2023]
Abstract
In vivo human diffusion MRI is by default performed using single-shot EPI with greater than 50-ms echo times and associated signal loss from transverse relaxation. The individual benefits of the current trends of increasing B0 to boost SNR and employing more advanced signal preparation schemes to improve the specificity for selected microstructural properties eventually may be cancelled by increased relaxation rates at high B0 and echo times with advanced encoding. Here, initial attempts to translate state-of-the-art diffusion-relaxation correlation methods from 3 T to 21.1 T are made to identify hurdles that need to be overcome to fulfill the promises of both high SNR and readily interpretable microstructural information.
Collapse
Affiliation(s)
- Jens T Rosenberg
- National High Magnetic Field Laboratory, Florida State University, Tallahassee FL, United States.
| | - Samuel C Grant
- National High Magnetic Field Laboratory, Florida State University, Tallahassee FL, United States; Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, FL, United States.
| | | |
Collapse
|
16
|
Le Ster C, Grant A, Van de Moortele PF, Monreal-Madrigal A, Adriany G, Vignaud A, Mauconduit F, Rabrait-Lerman C, Poser BA, Uğurbil K, Boulant N. Magnetic field strength dependent SNR gain at the center of a spherical phantom and up to 11.7T. Magn Reson Med 2022; 88:2131-2138. [PMID: 35849739 PMCID: PMC9420790 DOI: 10.1002/mrm.29391] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 06/06/2022] [Accepted: 06/27/2022] [Indexed: 02/05/2023]
Abstract
PURPOSE The SNR at the center of a spherical phantom of known electrical properties was measured in quasi-identical experimental conditions as a function of magnetic field strength between 3 T and 11.7 T. METHODS The SNR was measured at the center of a spherical water saline phantom with a gradient recalled echo sequence. Measurements were performed at NeuroSpin at 3, 7, and 11.7 T. The phantom was then shipped to Maastricht University and then to the University of Minnesota for additional data points at 7, 9.4, and 10.5 T. Experiments were carried out with the exact same type of birdcage volume coil (except at 3 T, where a similar coil was used) to attempt at isolating the evolution of SNR with field strength alone. Phantom electrical properties were characterized over the corresponding frequency range. RESULTS Electrical properties were found to barely vary over the frequency range. Removing the influence of the flip-angle excitation inhomogeneity was crucial, as expected. After such correction, measurements revealed a gain of SNR growing as B0 1.94 ± 0.16 compared with B0 2.13 according to ultimate intrinsic SNR theory. CONCLUSIONS By using quasi-identical experimental setups (RF volume coil, phantom, electrical properties, and protocol), this work reports experimental data between 3 T and 11.7 T, enabling the comparison with SNR theories in which conductivity and permittivity can be assumed to be constant with respect to field strength. According to ultimate SNR theory, these results can be reasonably extrapolated to the performance of receive arrays with greater than about 32 elements for central SNR in the same spherical phantom.
Collapse
Affiliation(s)
- Caroline Le Ster
- University of Paris-Saclay, CEA, CNRS, BAOBAB, NeuroSpin, Gif sur Yvette, France
| | - Andrea Grant
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota, USA
| | | | | | - Gregor Adriany
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota, USA
| | - Alexandre Vignaud
- University of Paris-Saclay, CEA, CNRS, BAOBAB, NeuroSpin, Gif sur Yvette, France
| | - Franck Mauconduit
- University of Paris-Saclay, CEA, CNRS, BAOBAB, NeuroSpin, Gif sur Yvette, France
| | | | - Benedikt A Poser
- Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Kâmil Uğurbil
- Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota, USA
| | - Nicolas Boulant
- University of Paris-Saclay, CEA, CNRS, BAOBAB, NeuroSpin, Gif sur Yvette, France
| |
Collapse
|
17
|
Liu J, Dona K, Hoshino G, Knirck S, Kurinsky N, Malaker M, Miller DW, Sonnenschein A, Awida MH, Barry PS, Berggren KK, Bowring D, Carosi G, Chang C, Chou A, Khatiwada R, Lewis S, Li J, Nam SW, Noroozian O, Zhou TX. Broadband Solenoidal Haloscope for Terahertz Axion Detection. PHYSICAL REVIEW LETTERS 2022; 128:131801. [PMID: 35426699 DOI: 10.1103/physrevlett.128.131801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 03/03/2022] [Indexed: 06/14/2023]
Abstract
We introduce the Broadband Reflector Experiment for Axion Detection (BREAD) conceptual design and science program. This haloscope plans to search for bosonic dark matter across the [10^{-3},1] eV ([0.24, 240] THz) mass range. BREAD proposes a cylindrical metal barrel to convert dark matter into photons, which a novel parabolic reflector design focuses onto a photosensor. This unique geometry enables enclosure in standard cryostats and high-field solenoids, overcoming limitations of current dish antennas. A pilot 0.7 m^{2} barrel experiment planned at Fermilab is projected to surpass existing dark photon coupling constraints by over a decade with one-day runtime. Axion sensitivity requires <10^{-20} W/sqrt[Hz] sensor noise equivalent power with a 10 T solenoid and 10 m^{2} barrel. We project BREAD sensitivity for various sensor technologies and discuss future prospects.
Collapse
Affiliation(s)
- Jesse Liu
- Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
- Department of Physics, University of Chicago, Chicago, Illinois 60637, USA
| | - Kristin Dona
- Department of Physics, University of Chicago, Chicago, Illinois 60637, USA
| | - Gabe Hoshino
- Department of Physics, University of Chicago, Chicago, Illinois 60637, USA
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
| | - Stefan Knirck
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
| | - Noah Kurinsky
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Kavli Institute for Cosmological Physics, University of Chicago, Chicago, Illinois 60637, USA
| | - Matthew Malaker
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
| | - David W Miller
- Department of Physics, University of Chicago, Chicago, Illinois 60637, USA
- Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637, USA
| | | | - Mohamed H Awida
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
| | - Peter S Barry
- Kavli Institute for Cosmological Physics, University of Chicago, Chicago, Illinois 60637, USA
- Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Karl K Berggren
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Daniel Bowring
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
| | - Gianpaolo Carosi
- Lawrence Livermore National Laboratory, Livermore, California 94551, USA
| | - Clarence Chang
- Kavli Institute for Cosmological Physics, University of Chicago, Chicago, Illinois 60637, USA
- Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Aaron Chou
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
| | - Rakshya Khatiwada
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
- Department of Physics, Illinois Institute of Technology, Chicago, Illinois 60616, USA
| | - Samantha Lewis
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
| | - Juliang Li
- Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Sae Woo Nam
- National Institute of Standards and Technology, Boulder, Colorado 80305, USA
| | - Omid Noroozian
- NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - Tony X Zhou
- Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| |
Collapse
|
18
|
Zeng C, Chen Z, Yang H, Fan Y, Fei L, Chen X, Zhang M. Advanced high resolution three-dimensional imaging to visualize the cerebral neurovascular network in stroke. Int J Biol Sci 2022; 18:552-571. [PMID: 35002509 PMCID: PMC8741851 DOI: 10.7150/ijbs.64373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 10/28/2021] [Indexed: 11/05/2022] Open
Abstract
As an important method to accurately and timely diagnose stroke and study physiological characteristics and pathological mechanism in it, imaging technology has gone through more than a century of iteration. The interaction of cells densely packed in the brain is three-dimensional (3D), but the flat images brought by traditional visualization methods show only a few cells and ignore connections outside the slices. The increased resolution allows for a more microscopic and underlying view. Today's intuitive 3D imagings of micron or even nanometer scale are showing its essentiality in stroke. In recent years, 3D imaging technology has gained rapid development. With the overhaul of imaging mediums and the innovation of imaging mode, the resolution has been significantly improved, endowing researchers with the capability of holistic observation of a large volume, real-time monitoring of tiny voxels, and quantitative measurement of spatial parameters. In this review, we will summarize the current methods of high-resolution 3D imaging applied in stroke.
Collapse
Affiliation(s)
- Chudai Zeng
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| | - Zhuohui Chen
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| | - Haojun Yang
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| | - Yishu Fan
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| | - Lujing Fei
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| | - Xinghang Chen
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| | - Mengqi Zhang
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan, China, 410008.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China, 410008
| |
Collapse
|
19
|
Khan MH, Huang X, Tian X, Ouyang C, Wang D, Feng S, Chen J, Xue T, Bao J, Zhang X. Short- and long-term effects of 3.5-23.0 Tesla ultra-high magnetic fields on mice behaviour. Eur Radiol 2022; 32:5596-5605. [PMID: 35294587 DOI: 10.1007/s00330-022-08677-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 02/15/2022] [Accepted: 02/17/2022] [Indexed: 12/31/2022]
Abstract
OBJECTIVES Higher static magnetic field (SMF) enables higher imaging capability in magnetic resonance imaging (MRI), which encourages the development of ultra-high field MRIs above 20 T with a prerequisite for safety issues. However, animal tests of ≥ 20 T SMF exposure are very limited. The objective of the current study is to evaluate mice behaviour consequences of 3.5-23.0 T SMF exposure. METHODS We systematically examined 112 mice for their short- and long-term behaviour responses to a 2-h exposure of 3.5-23.0 T SMFs. Locomotor activity and cognitive functions were measured by five behaviour tests, including balance beam, open field, elevated plus maze, three-chamber social recognition, and Morris water maze tests. RESULTS Besides the transient short-term impairment of the sense of balance and locomotor activity, the 3.5-23.0 T SMFs did not have long-term negative effects on mice locomotion, anxiety level, social behaviour, or memory. In contrast, we observed anxiolytic effects and positive effects on social and spatial memory of SMFs, which is likely correlated with the significantly increased CaMKII level in the hippocampus region of high SMF-treated mice. CONCLUSIONS Our study showed that the short exposures to high-field SMFs up to 23.0 T have negligible side effects on healthy mice and may even have beneficial outcomes in mice mood and memory, which is pertinent to the future medical application of ultra-high field SMFs in MRIs and beyond. KEY POINTS • Short-term exposure to magnetic fields up to 23.0 T is safe for mice. • High-field static magnetic field exposure transiently reduced mice locomotion. • High-field static magnetic field enhances memory while reduces the anxiety level.
Collapse
Affiliation(s)
- Md Hasanuzzaman Khan
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, CAS Key Laboratory of Brain Function and Disease, School of Life Sciences, Eye Center, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Huangshan Road 443, Hefei, 230026, Anhui, China
| | - Xinfeng Huang
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, CAS Key Laboratory of Brain Function and Disease, School of Life Sciences, Eye Center, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Huangshan Road 443, Hefei, 230026, Anhui, China
| | - Xiaofei Tian
- Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, Anhui, China
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Shushanhu Road #350, Hefei, 230031, Anhui, China
| | - Changjie Ouyang
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, CAS Key Laboratory of Brain Function and Disease, School of Life Sciences, Eye Center, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Huangshan Road 443, Hefei, 230026, Anhui, China
- Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, Anhui, China
| | - Dongmei Wang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Shushanhu Road #350, Hefei, 230031, Anhui, China
| | - Shuang Feng
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Shushanhu Road #350, Hefei, 230031, Anhui, China
| | - Jutao Chen
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, CAS Key Laboratory of Brain Function and Disease, School of Life Sciences, Eye Center, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Huangshan Road 443, Hefei, 230026, Anhui, China
| | - Tian Xue
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, CAS Key Laboratory of Brain Function and Disease, School of Life Sciences, Eye Center, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Huangshan Road 443, Hefei, 230026, Anhui, China.
| | - Jin Bao
- Hefei National Laboratory for Physical Sciences at the Microscale, Neurodegenerative Disorder Research Center, CAS Key Laboratory of Brain Function and Disease, School of Life Sciences, Eye Center, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Huangshan Road 443, Hefei, 230026, Anhui, China.
- Shenzhen Neher Neural Plasticity Laboratory, the Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences (CAS); Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, 518055, China.
| | - Xin Zhang
- Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, Anhui, China.
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Shushanhu Road #350, Hefei, 230031, Anhui, China.
- International Magnetobiology Frontier Research Center, Science Island, Hefei, 230031, Anhui, China.
| |
Collapse
|
20
|
Vilca-Melendez S, Uthaug MV, Griffin JL. 1H Nuclear Magnetic Resonance: A Future Approach to the Metabolic Profiling of Psychedelics in Human Biofluids? Front Psychiatry 2021; 12:742856. [PMID: 34966300 PMCID: PMC8710695 DOI: 10.3389/fpsyt.2021.742856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 11/18/2021] [Indexed: 11/25/2022] Open
Abstract
While psychedelics may have therapeutic potential for treating mental health disorders such as depression, further research is needed to better understand their biological effects and mechanisms of action when considering the development of future novel therapy approaches. Psychedelic research could potentially benefit from the integration of metabonomics by proton nuclear magnetic resonance (1H NMR) spectroscopy which is an analytical chemistry-based approach that can measure the breakdown of drugs into their metabolites and their metabolic consequences from various biofluids. We have performed a systematic review with the primary aim of exploring published literature where 1H NMR analysed psychedelic substances including psilocin, lysergic acid diethylamide (LSD), LSD derivatives, N,N-dimethyltryptamine (DMT), 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) and bufotenin. The second aim was to assess the benefits and limitations of 1H NMR spectroscopy-based metabolomics as a tool in psychedelic research and the final aim was to explore potential future directions. We found that the most current use of 1H NMR in psychedelic research has been for the structural elucidation and analytical characterisation of psychedelic molecules and that no papers used 1H NMR in the metabolic profiling of biofluids, thus exposing a current research gap and the underuse of 1H NMR. The efficacy of 1H NMR spectroscopy was also compared to mass spectrometry, where both metabonomics techniques have previously shown to be appropriate for biofluid analysis in other applications. Additionally, potential future directions for psychedelic research were identified as real-time NMR, in vivo 1H nuclear magnetic resonance spectroscopy (MRS) and 1H NMR studies of the gut microbiome. Further psychedelic studies need to be conducted that incorporate the use of 1H NMR spectroscopy in the analysis of metabolites both in the peripheral biofluids and in vivo to determine whether it will be an effective future approach for clinical and naturalistic research.
Collapse
Affiliation(s)
- Sylvana Vilca-Melendez
- Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Malin V. Uthaug
- The Centre for Psychedelic Research, Department of Brain Sciences, Faculty of Medicine, Imperial College London, London, United Kingdom
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Julian L. Griffin
- Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London, United Kingdom
| |
Collapse
|
21
|
Polimeni JR, Lewis LD. Imaging faster neural dynamics with fast fMRI: A need for updated models of the hemodynamic response. Prog Neurobiol 2021; 207:102174. [PMID: 34525404 PMCID: PMC8688322 DOI: 10.1016/j.pneurobio.2021.102174] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 07/30/2021] [Accepted: 09/08/2021] [Indexed: 12/20/2022]
Abstract
Fast fMRI enables the detection of neural dynamics over timescales of hundreds of milliseconds, suggesting it may provide a new avenue for studying subsecond neural processes in the human brain. The magnitudes of these fast fMRI dynamics are far greater than predicted by canonical models of the hemodynamic response. Several studies have established nonlinear properties of the hemodynamic response that have significant implications for fast fMRI. We first review nonlinear properties of the hemodynamic response function that may underlie fast fMRI signals. We then illustrate the breakdown of canonical hemodynamic response models in the context of fast neural dynamics. We will then argue that the canonical hemodynamic response function is not likely to reflect the BOLD response to neuronal activity driven by sparse or naturalistic stimuli or perhaps to spontaneous neuronal fluctuations in the resting state. These properties suggest that fast fMRI is capable of tracking surprisingly fast neuronal dynamics, and we discuss the neuroscientific questions that could be addressed using this approach.
Collapse
Affiliation(s)
- Jonathan R Polimeni
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Radiology, Harvard Medical School, Boston, MA, USA; Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Laura D Lewis
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Biomedical Engineering, Boston University, Boston, MA, USA.
| |
Collapse
|
22
|
Deelchand DK, Ho ML, Nestrasil I. Ultra-High-Field Imaging of the Pediatric Brain and Spinal Cord. Magn Reson Imaging Clin N Am 2021; 29:643-653. [PMID: 34717851 DOI: 10.1016/j.mric.2021.06.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Neuroimaging with ultra-high field magnets (≥7T) provides superior signal-to-noise, spatial resolution and tissue contrast; but also greater safety concerns, longer scanning times, and increased distortion and field inhomogeneity. Brain and spinal cord anatomic microstructure and function imaged in greater detail offers improved lesion detection, delineation, and characterization. The ongoing development of novel imaging contrasts and translation of cutting-edge sequences will aid more accurate, sensitive, and precise diagnosis, interventional planning, and follow-up for a variety of pathologic conditions.
Collapse
Affiliation(s)
- Dinesh Kumar Deelchand
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, 2021 6th Street Southeast, Minneapolis, MN 55455, USA
| | - Mai-Lan Ho
- Department of Radiology, Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA
| | - Igor Nestrasil
- Masonic Institute for the Developing Brain, Division of Clinical Behavioral Neuroscience, Department of Pediatrics, University of Minnesota, 2025 East River Parkway, Minneapolis, MN 55414, USA.
| |
Collapse
|
23
|
Platt T, Ladd ME, Paech D. 7 Tesla and Beyond: Advanced Methods and Clinical Applications in Magnetic Resonance Imaging. Invest Radiol 2021; 56:705-725. [PMID: 34510098 PMCID: PMC8505159 DOI: 10.1097/rli.0000000000000820] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 08/07/2021] [Accepted: 08/07/2021] [Indexed: 12/15/2022]
Abstract
ABSTRACT Ultrahigh magnetic fields offer significantly higher signal-to-noise ratio, and several magnetic resonance applications additionally benefit from a higher contrast-to-noise ratio, with static magnetic field strengths of B0 ≥ 7 T currently being referred to as ultrahigh fields (UHFs). The advantages of UHF can be used to resolve structures more precisely or to visualize physiological/pathophysiological effects that would be difficult or even impossible to detect at lower field strengths. However, with these advantages also come challenges, such as inhomogeneities applying standard radiofrequency excitation techniques, higher energy deposition in the human body, and enhanced B0 field inhomogeneities. The advantages but also the challenges of UHF as well as promising advanced methodological developments and clinical applications that particularly benefit from UHF are discussed in this review article.
Collapse
Affiliation(s)
- Tanja Platt
- From the Medical Physics in Radiology, German Cancer Research Center (DKFZ)
| | - Mark E. Ladd
- From the Medical Physics in Radiology, German Cancer Research Center (DKFZ)
- Faculty of Physics and Astronomy
- Faculty of Medicine, University of Heidelberg, Heidelberg
- Erwin L. Hahn Institute for MRI, University of Duisburg-Essen, Essen
| | - Daniel Paech
- Division of Radiology, German Cancer Research Center (DKFZ), Heidelberg
- Clinic for Neuroradiology, University of Bonn, Bonn, Germany
| |
Collapse
|
24
|
Barati S, Enferadi M, Sarkar S, Geramifar P. The effect of magnetic field strength on the positron range and projected annihilation artifact in integrated PET/MR systems: A GATE Monte Carlo study. Med Phys 2021; 48:7712-7724. [PMID: 34706098 DOI: 10.1002/mp.15313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 09/19/2021] [Accepted: 10/12/2021] [Indexed: 12/11/2022] Open
Abstract
PURPOSE With improvements in positron emission tomography/magnetic resonance imaging (PET/MRI) over the last decade, there is a need to investigate the projected annihilation (shine-through) artifact and resolution impact for different PET radiopharmaceuticals, magnetic field (MF) strengths, and tissues. METHODS The GATE Monte Carlo (MC) simulation was used to simulate the annihilation distribution of positrons in different tissues and MFs. The positron distribution was studied in magnetic field (MF) intensities up to 15 T for 11 C, 13 N, 15 O, 18 F, 68 Ga, and 82 Rb. Moreover, the image quality in terms of the occurrence of projected annihilation artifacts was investigated using the 4D anthropomorphic digital extended cardiac-torso (XCAT) phantom. RESULTS Positron ranges were restricted across the directions perpendicular to the MF, but no change along the direction of the MF was detected. The projected annihilation artifacts were observed with the presence of MF in the sagittal and coronal view of PET images prepared from the XCAT phantom. The intensity of artifact was constant in MFs higher than 3 T. The significant effect of the MF on resolution improvement was observed in soft tissue for 68 Ga in 7 T and 82 Rb in 3 and 7 T, while higher MFs have no impact on resolution. The improvement of resolution in the lung tissue was observed for the medium- and high-energy radionuclides in 7 T MF. CONCLUSION The MF can create the projected annihilation artifact in the boundary of air cavities and other tissues for medium- and high-energy radionuclides especially for 68 Ga in clinical studies. In addition, the strength of the MFs more than 3 T was ineffective on the intensity of the projected annihilation artifact. In a clinical PET/MR scanner, MF has remarkable spatial resolution improvement in lung tissue, especially for medium- and high-energy radionuclides, and negligible effect in bone and soft tissue for most radionuclides.
Collapse
Affiliation(s)
- Sepideh Barati
- Department of Nuclear Medicine, Vali-Asr Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Milad Enferadi
- Division of Molecular Imaging and Theranostics, Department of Nuclear Medicine, University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria
| | - Saeed Sarkar
- Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran
| | - Parham Geramifar
- Research Center for Nuclear Medicine, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
25
|
Goddings AL, Roalf D, Lebel C, Tamnes CK. Development of white matter microstructure and executive functions during childhood and adolescence: a review of diffusion MRI studies. Dev Cogn Neurosci 2021; 51:101008. [PMID: 34492631 PMCID: PMC8424510 DOI: 10.1016/j.dcn.2021.101008] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 07/26/2021] [Accepted: 08/24/2021] [Indexed: 12/13/2022] Open
Abstract
Diffusion magnetic resonance imaging (dMRI) provides indirect measures of white matter microstructure that can be used to make inferences about structural connectivity within the brain. Over the last decade, a growing literature of cross-sectional and longitudinal studies have documented relationships between dMRI indices and cognitive development. In this review, we provide a brief overview of dMRI methods and how they can be used to study white matter and connectivity and review the extant literature examining the links between dMRI indices and executive functions during development. We explore the links between white matter microstructure and specific executive functions: inhibition, working memory and cognitive shifting, as well as performance on complex executive function tasks. Concordance in findings across studies are highlighted, and potential explanations for discrepancies between results, together with challenges with using dMRI in child and adolescent populations, are discussed. Finally, we explore future directions that are necessary to better understand the links between child and adolescent development of structural connectivity of the brain and executive functions.
Collapse
Affiliation(s)
- Anne-Lise Goddings
- UCL Great Ormond Street Institute of Child Health, University College London, UK.
| | - David Roalf
- Department of Psychiatry, University of Pennsylvania, USA; Lifespan Brain Institute, Children's Hospital of Philadelphia and the University of Pennsylvania, USA
| | - Catherine Lebel
- Department of Radiology, University of Calgary, Alberta, Canada
| | - Christian K Tamnes
- PROMENTA Research Center, Department of Psychology, University of Oslo, Norway; NORMENT, Institute of Clinical Medicine, University of Oslo, Norway; Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway
| |
Collapse
|
26
|
Vachha B, Huang SY. MRI with ultrahigh field strength and high-performance gradients: challenges and opportunities for clinical neuroimaging at 7 T and beyond. Eur Radiol Exp 2021; 5:35. [PMID: 34435246 PMCID: PMC8387544 DOI: 10.1186/s41747-021-00216-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 03/30/2021] [Indexed: 12/12/2022] Open
Abstract
Research in ultrahigh magnetic field strength combined with ultrahigh and ultrafast gradient technology has provided enormous gains in sensitivity, resolution, and contrast for neuroimaging. This article provides an overview of the technical advantages and challenges of performing clinical neuroimaging studies at ultrahigh magnetic field strength combined with ultrahigh and ultrafast gradient technology. Emerging clinical applications of 7-T MRI and state-of-the-art gradient systems equipped with up to 300 mT/m gradient strength are reviewed, and the impact and benefits of such advances to anatomical, structural and functional MRI are discussed in a variety of neurological conditions. Finally, an outlook and future directions for ultrahigh field MRI combined with ultrahigh and ultrafast gradient technology in neuroimaging are examined.
Collapse
Affiliation(s)
- Behroze Vachha
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Ave, New York, NY, 10065, USA
| | - Susie Y Huang
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, 149 13th Street, Room 2301, Charlestown, MA, 02129, USA.
| |
Collapse
|
27
|
Cosottini M, Roccatagliata L. Neuroimaging at 7 T: are we ready for clinical transition? Eur Radiol Exp 2021; 5:37. [PMID: 34435257 PMCID: PMC8387509 DOI: 10.1186/s41747-021-00234-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 07/19/2021] [Indexed: 12/23/2022] Open
Abstract
In the last 20 years, ultra-high field (UHF) magnetic resonance imaging (MRI) has become an outstanding research tool for the study of the human brain, with 90 of these scanners installed today, worldwide. The recent clearances from regulatory bodies in the USA and Europe to 7-T clinical systems have set the ground for a transition from pure research applications to research and clinical use of these systems. As today, UFH neuroimaging is demonstrating clinical value and, given the importance of this topic for both preclinical scientists and clinical neuroradiologists, European Radiology Experimental is launching a thematic series entitled "7-T neuro MRI: from research to clinic", consisting of peer-reviewed articles, invited or spontaneously submitted, on topics selected by the guest editors, describing the state of the art of UHF MRI neuroimaging across different pathologies, as well as related clinical applications. In this editorial, we discuss some of the challenges related to the clinical use of 7-T scanners and the strengths and weaknesses of clinical imaging at UHF.
Collapse
Affiliation(s)
- Mirco Cosottini
- Department of Translational Research On New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Luca Roccatagliata
- Department of Health Sciences (DISSAL), University of Genoa, Via Pastore 1, 16132, Genoa, Italy.
- Department of Neuroradiology, Ospedale Policlinico San Martino IRCCS, Genoa, Italy.
| |
Collapse
|
28
|
Design of a 15 T hybrid superconducting magnet. FUSION ENGINEERING AND DESIGN 2021. [DOI: 10.1016/j.fusengdes.2021.112294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
29
|
Gao M, Sun H, Cheng X, Gao D, Qiao M. Magnetic resonance imaging in mood disorders: a bibliometric analysis from 1999 to 2020. Clin Transl Imaging 2021. [DOI: 10.1007/s40336-021-00425-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Objective
Globally, mood disorders are highly prevalent, and are associated with increased morbidity and mortalities. Magnetic resonance imaging is widely used in the study of mood disorders. However, bibliometric analyses of the state of this field are lacking.
Methods
A literature search in the web of science core collection (WoSCC) for the period between 1945 and 2020 returned 3073 results. Data extracted from these publications include, publication year, journal names, countries of origin, institutions, author names and research areas. The bibliometric method, CiteSpace V and key words analysis were used to visualize the collaboration network and identify research trends, respectively.
Results
Since it was first reported in 1999, the use of magnetic resonance imaging in studies on mood disorders has been increasing. Biological psychiatry is the core journal that has extensively published on this topic, while the UNIV PITTSBURGH, USA, has the highest published papers on this topic. Keyword analysis indicated that studies on depression, bipolar disorders, and schizophrenia, with a focus on specific brain regions, including amygdala, prefrontal cortex and anterior cingulate cortex are key research topics.
Conclusion
Brain structure and network, sex differences, and treatment-associated brain changes are key topics of future research.
Collapse
|
30
|
Tian X, Lv Y, Fan Y, Wang Z, Yu B, Song C, Lu Q, Xi C, Pi L, Zhang X. Safety evaluation of mice exposed to 7.0-33.0 T high-static magnetic fields. J Magn Reson Imaging 2020; 53:1872-1884. [PMID: 33382516 DOI: 10.1002/jmri.27496] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 12/14/2020] [Accepted: 12/16/2020] [Indexed: 01/26/2023] Open
Abstract
Magnetic resonance imaging (MRI) of 7 T and higher can provide superior image resolution and capability. Clinical tests have been performed in 9.4 T MRI, and 21.1 T small-bore-size MRI has also been tested in rodents. Although the safety issue is a prerequisite for their future medical application, there are very few relevant studies for the safety of static magnetic fields (SMFs) of ≧20 T. The aim of this study was to assess the biological effects of 7.0-33.0 T SMFs in healthy adult mice. This was a prospective study, in which 104 healthy adult C57BL/6 mice were divided into control, sham control, and 7.0-33.0 T SMF-exposed groups.The sham control group and SMF group were handled identically, except for the electric current for producing SMF. A separate control group was placed outside the magnet and their data were used as normal range. After 1 h exposure, all mice were routinely fed for another 2 months while their body weight and food/water consumption were monitored. After 2 months, their complete blood count, blood biochemistry, key organ weight, and histomorphology were examined. All data are normally distributed. Differences between the sham and SMF-exposed groups were evaluated by unpaired t test. Most indicators did not show statistically significant changes or were still within the normal ranges, with only a few exceptions. For example, mono % in Group 2 (11.1 T) is 6.03 ± 1.43% while the normal range is 6.60-9.90% (p < 0.05). The cholesterol level in 33 T group is 3.38 ± 0.36 mmol/L while the normal range is 2.48-3.29 mmol/L (p < 0.05). The high-density lipoprotein cholesterol level in 33 T group is 2.54 ± 0.29 mmol/L while the normal reference range is 1.89-2.43 mmol/L (p < 0.01). Exposure to 7.0-33.0 T for 1 h did not have detrimental effects on normal adult mice. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY STAGE: 1.
Collapse
Affiliation(s)
- Xiaofei Tian
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China.,Institutes of Physical Science and Information Technology, Anhui University, Hefei, China
| | - Yue Lv
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China.,Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, China
| | - Yixiang Fan
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China.,Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, China
| | - Ze Wang
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China.,Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, China
| | - Biao Yu
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China.,Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, China
| | - Chao Song
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China.,Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, China
| | - Qingyou Lu
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China.,Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, China.,Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, Hefei, China
| | - Chuanying Xi
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China
| | - Li Pi
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China
| | - Xin Zhang
- High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, China.,Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, China.,Institutes of Physical Science and Information Technology, Anhui University, Hefei, China
| |
Collapse
|
31
|
Wu K, Wu Y, Shi Y, Xu A, Dai C, Hao Q, Han H, Liu X, Ma Y, Zhang Y, Wu J, Hussain MT. An improved passive shimming approach to design correction iron pieces for high field MRI. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:124105. [PMID: 33379965 DOI: 10.1063/5.0032047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 12/07/2020] [Indexed: 06/12/2023]
Abstract
This paper proposes a new passive shimming method to design correction iron pieces for compensating field impurities generated by the main magnets of high field magnetic resonance imaging (MRI) for human body imaging. First, the relationship formula of a magnetic dipole to any field point in space is established. Then, a sensitivity matrix in the form of spherical harmonic expansions can be set up based on the contribution of each shim piece to each field point. Next, an optimization procedure of linear programming is applied to determine the location and thickness of the ferromagnetic shim pieces. This is different from the previous methods that consider that all magnetic moments for each magnetized iron piece are located only at its central position, which may cause some intrinsic errors. This method takes the shim piece's volume into account and gives more accurate results in a sensitivity matrix by means of integration in the azimuthal and axial directions while the radial (thickness) direction remains constant. Finally, a case study combining the analytical method and a 3D finite element analysis simulation demonstrates that the new approach provides better results in terms of homogeneity. The method presented can also be used to design passive shims for various practical MRI applications.
Collapse
Affiliation(s)
- Kaihong Wu
- Institute Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Yu Wu
- Institute Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Yi Shi
- Institute Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Aihua Xu
- Changzhou Vocational Institute of Mechatronic Technology, Changzhou 213164, China
| | - Chao Dai
- Institute Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Qiangwang Hao
- Institute Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Houxiang Han
- Institute Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Xiaochuan Liu
- Institute Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Yuanyuan Ma
- Institute Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Yongliang Zhang
- Institute Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Junrong Wu
- Institute Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - M T Hussain
- Institute Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| |
Collapse
|
32
|
Choi CH, Stegmayr C, Shymanskaya A, Worthoff WA, da Silva NA, Felder J, Langen KJ, Shah NJ. An in vivo multimodal feasibility study in a rat brain tumour model using flexible multinuclear MR and PET systems. EJNMMI Phys 2020; 7:50. [PMID: 32728773 PMCID: PMC7391464 DOI: 10.1186/s40658-020-00319-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 07/12/2020] [Indexed: 11/16/2022] Open
Abstract
Background In addition to the structural information afforded by 1H MRI, the use of X-nuclei, such as sodium-23 (23Na) or phosphorus-31 (31P), offers important complementary information concerning physiological and biochemical parameters. By then combining this technique with PET, which provides valuable insight into a wide range of metabolic and molecular processes by using of a variety of radioactive tracers, the scope of medical imaging and diagnostics can be significantly increased. While the use of multimodal imaging is undoubtedly advantageous, identifying the optimal combination of these parameters to diagnose a specific dysfunction is very important and is advanced by the use of sophisticated imaging techniques in specific animal models. Methods In this pilot study, rats with intracerebral 9L gliosarcomas were used to explore a combination of sequential multinuclear MRI using a sophisticated switchable coil set in a small animal 9.4 T MRI scanner and, subsequently, a small animal PET with the tumour tracer O-(2-[18F]-fluoroethyl)-L-tyrosine ([18F]FET). This made it possible for in vivo multinuclear MR-PET experiments to be conducted without compromising the performance of either multinuclear MR or PET. Results High-quality in vivo images and spectra including high-resolution 1H imaging, 23Na-weighted imaging, detection of 31P metabolites and [18F]FET uptake were obtained, allowing the characterisation of tumour tissues in comparison to a healthy brain. It has been reported in the literature that these parameters are useful in the identification of the genetic profile of gliomas, particularly concerning the mutation of the isocitrate hydrogenase gene, which is highly relevant for treatment strategy. Conclusions The combination of multinuclear MR and PET in, for example, brain tumour models with specific genetic mutations will enable the physiological background of signal alterations to be explored and the identification of the optimal combination of imaging parameters for the non-invasive characterisation of the molecular profile of tumours.
Collapse
Affiliation(s)
- Chang-Hoon Choi
- Institute of Neuroscience and Medicine-4, INM-4, Forschungszentrum Jülich, Germany
| | - Carina Stegmayr
- Institute of Neuroscience and Medicine-4, INM-4, Forschungszentrum Jülich, Germany
| | | | - Wieland A Worthoff
- Institute of Neuroscience and Medicine-4, INM-4, Forschungszentrum Jülich, Germany
| | - Nuno A da Silva
- Institute of Neuroscience and Medicine-4, INM-4, Forschungszentrum Jülich, Germany
| | - Jörg Felder
- Institute of Neuroscience and Medicine-4, INM-4, Forschungszentrum Jülich, Germany
| | - Karl-Josef Langen
- Institute of Neuroscience and Medicine-4, INM-4, Forschungszentrum Jülich, Germany.,Department of Nuclear Medicine, RWTH Aachen University Hospital, Aachen, Germany.,Jülich-Aachen Research Alliance (JARA)-Section JARA-BRAIN, Aachen, Germany
| | - N Jon Shah
- Institute of Neuroscience and Medicine-4, INM-4, Forschungszentrum Jülich, Germany. .,Institute of Neuroscience and Medicine-11, INM-11, JARA, Forschungszentrum Jülich, Germany. .,JARA-BRAIN-Translational Medicine, Aachen, Germany. .,Department of Neurology, RWTH Aachen University, Aachen, Germany.
| |
Collapse
|
33
|
Kang SG, Cho SE. Neuroimaging Biomarkers for Predicting Treatment Response and Recurrence of Major Depressive Disorder. Int J Mol Sci 2020; 21:ijms21062148. [PMID: 32245086 PMCID: PMC7139562 DOI: 10.3390/ijms21062148] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 03/12/2020] [Accepted: 03/19/2020] [Indexed: 12/26/2022] Open
Abstract
The acute treatment duration for major depressive disorder (MDD) is 8 weeks or more. Treatment of patients with MDD without predictors of treatment response and future recurrence presents challenges and clinical problems to patients and physicians. Recently, many neuroimaging studies have been published on biomarkers for treatment response and recurrence of MDD using various methods such as brain volumetric magnetic resonance imaging (MRI), functional MRI (resting-state and affective tasks), diffusion tensor imaging, magnetic resonance spectroscopy, near-infrared spectroscopy, and molecular imaging (i.e., positron emission tomography and single photon emission computed tomography). The results have been inconsistent, and we hypothesize that this could be due to small sample size; different study design, including eligibility criteria; and differences in the imaging and analysis techniques. In the future, we suggest a more sophisticated research design, larger sample size, and a more comprehensive integration including genetics to establish biomarkers for the prediction of treatment response and recurrence of MDD.
Collapse
|
34
|
Menezes de Oliveira M, Pang JC, Robinson PA, Liu X, Schira MM. Feasibility of functional magnetic resonance imaging of ocular dominance and orientation preference in primary visual cortex. PLoS Comput Biol 2019; 15:e1007418. [PMID: 31682598 PMCID: PMC6855504 DOI: 10.1371/journal.pcbi.1007418] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 11/14/2019] [Accepted: 09/23/2019] [Indexed: 11/19/2022] Open
Abstract
A recent hemodynamic model is extended and applied to simulate and explore the feasibility of detecting ocular dominance (OD) and orientation preference (OP) columns in primary visual cortex by means of functional magnetic resonance imaging (fMRI). The stimulation entails a short oriented bar stimulus being presented to one eye and mapped to cortical neurons with corresponding OD and OP selectivity. Activated neurons project via patchy connectivity to excite other neurons with similar OP in nearby visual fields located preferentially along the direction of stimulus orientation. The resulting blood oxygen level dependent (BOLD) response is estimated numerically via the model's spatiotemporal hemodynamic response function. The results are then used to explore the feasibility of detecting spatial OD-OP modulation, either directly measuring BOLD or by using Wiener deconvolution to filter the image and estimate the underlying neural activity. The effect of noise is also considered and it is estimated that direct detection can be robust for fMRI resolution of around 0.5 mm, whereas detection with Wiener deconvolution is possible at a broader range from 0.125 mm to 1 mm resolution. The detection of OD-OP features is strongly dependent on hemodynamic parameters, such as low velocity and high damping reduce response spreads and result in less blurring. The short-bar stimulus that gives the most detectable response is found to occur when neural projections are at 45 relative to the edge of local OD boundaries, which provides a constraint on the OD-OP architecture even when it is not fully resolved.
Collapse
Affiliation(s)
- Marilia Menezes de Oliveira
- School of Physics, University of Sydney, New South Wales, Australia
- Center for Integrative Brain Function, University of Sydney, New South Wales, Australia
| | - James C. Pang
- School of Physics, University of Sydney, New South Wales, Australia
- Center for Integrative Brain Function, University of Sydney, New South Wales, Australia
- QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Peter A. Robinson
- School of Physics, University of Sydney, New South Wales, Australia
- Center for Integrative Brain Function, University of Sydney, New South Wales, Australia
| | - Xiaochen Liu
- School of Physics, University of Sydney, New South Wales, Australia
- Center for Integrative Brain Function, University of Sydney, New South Wales, Australia
| | - Mark M. Schira
- School of Psychology, University of Wollongong, Wollongong, New South Wales, Australia
| |
Collapse
|
35
|
Lee D, King J, Thomsen S, Hirabayashi M, An J. Comparison Of Surgical Outcomes Between Excisional Goniotomy Using The Kahook Dual Blade And iStent Trabecular Micro-Bypass Stent In Combination With Phacoemulsification. Clin Ophthalmol 2019; 13:2097-2102. [PMID: 31749607 PMCID: PMC6818539 DOI: 10.2147/opth.s224109] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 09/23/2019] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To compare 6-month surgical outcomes of patients who underwent phacoemulsification (Phaco) combined with iStent implantation (iStent) versus excisional goniotomy using Kahook Dual Blade (KDB). METHODS Retrospective comparative case series of 58 iStent-Phaco eyes and 44 KDB-Phaco eyes operated upon by a single surgeon between 2016 and 2018. Preoperative, intraoperative, and postoperative intraocular pressure (IOP) and IOP-lowering medication data were collected. The primary outcome was the proportion of eyes using ≥1 fewer IOP-lowering medication at Month 6 while maintaining IOP ≤ 18 mmHg. RESULTS Baseline IOP was 17.2 (standard error 0.7) in the KDB-Phaco group using a mean of 1.9 (0.2) medications; at Month 6, mean IOP was 14.8 mmHg P=0.002) on 1.0 (0.2) medications (P<0.002). Baseline IOP was 16.7 (0.4) in the iStent-Phaco group using a mean of 1.4 (0.1) medications; at Month 6, mean IOP was 14.2 mmHg (P<0.002) on 1.4 (0.1) medications P=0.374). Changes in IOP and medications were not significantly different between groups (P>0.05). Significantly more KDB-Phaco eyes than iStent-Phaco eyes (43.2% vs 17.2%, P=0.004) were using ≥1 fewer medications while maintaining IOP ≤18 mmHg at Month 6. Adverse events were uncommon and similar in nature and frequency between groups with the exception that more KDB-Phaco eyes than iStent-Phaco eyes (8 [18.2%] versus 1 [1.7%]) experienced an IOP elevation presumed to be related to steroid use. CONCLUSION KDB-Phaco and iStent-Phaco provided comparable IOP and medication reductions. The proportion of eyes able to discontinue 1 or more medications while maintaining IOP ≤ 18 mmHg was significantly greater in eyes undergoing KDB-Phaco.
Collapse
Affiliation(s)
- Dayeong Lee
- School of Medicine, University of Missouri School of Medicine, Columbia, MO, USA
| | - Joshua King
- School of Medicine, University of Missouri School of Medicine, Columbia, MO, USA
| | - Samuel Thomsen
- School of Medicine, University of Missouri School of Medicine, Columbia, MO, USA
- Department of Ophthalmology, Mason Eye Institute, University of Missouri School of Medicine, Columbia, MO, USA
| | - Matthew Hirabayashi
- School of Medicine, University of Missouri School of Medicine, Columbia, MO, USA
| | - Jella An
- School of Medicine, University of Missouri School of Medicine, Columbia, MO, USA
- Department of Ophthalmology, Mason Eye Institute, University of Missouri School of Medicine, Columbia, MO, USA
| |
Collapse
|
36
|
ElMallah MK, Seibold LK, Kahook MY, Williamson BK, Singh IP, Dorairaj SK. 12-Month Retrospective Comparison of Kahook Dual Blade Excisional Goniotomy with Istent Trabecular Bypass Device Implantation in Glaucomatous Eyes at the Time of Cataract Surgery. Adv Ther 2019; 36:2515-2527. [PMID: 31317390 PMCID: PMC6822852 DOI: 10.1007/s12325-019-01025-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Indexed: 10/30/2022]
Abstract
PURPOSE To compare the efficacy and safety of combined cataract extraction and either excisional goniotomy performed with the Kahook Dual Blade (KDB; phaco-KDB group) or single iStent trabecular bypass implantation (phaco-iStent group) in eyes with mild to moderate glaucoma and visually significant cataract. METHODS This was a retrospective analysis of 315 eyes from 230 adults with mild or moderate glaucoma treated with one or more intraocular pressure (IOP)-lowering medications (190 eyes of 134 subjects in the phaco-KDB group and 125 eyes of 96 subjects in the phaco-iStent group) that required no subsequent surgical intervention for IOP control through 12 months of follow-up. Data included best-corrected visual acuity (BCVA), IOP, and IOP-lowering medications, collected preoperatively and at 1 week and 1, 3, 6, and 12 months postoperatively as well as intraoperative and postoperative adverse events. The primary efficacy outcomes were the proportion of subjects in each group achieving ≥ 20% IOP reduction and ≥ 1 medication reduction at month 12. Subgroup analysis by baseline IOP (≤ 18 mmHg vs. > 18 mmHg) was also performed. RESULTS Mean (standard error) baseline IOP was 18.2 (0.3) mmHg in the phaco-KDB group and 16.7 (0.3) mmHg in the phaco-iStent group (p = 0.001). Statistically significant mean IOP and mean IOP medication reductions from baseline were achieved at all time points in both groups. Mean IOP reductions were significantly greater in the phaco-KDB group than in the phaco-iStent group at all time points including month 12 [- 5.0 (0.3) mmHg vs. - 2.3 (0.4) mmHg, p < 0.001], while mean medication reductions were similar between groups at all time points except week 1, when greater mean medication reduction was seen in the phaco-iStent group (- 1.23 vs. - 0.60 medications, p < 0.001). At month 12, IOP reductions ≥ 20% were achieved by 64.2% and 41.6% (p < 0.001) in the phaco-KDB and phaco-iStent groups, respectively, and IOP medication reductions of ≥ 1 medication were achieved by 80.4% and 77.4% (p = 0.522), respectively. Intraocular pressure subgroup analysis revealed significant reductions in IOP-lowering medications without compromise of IOP control in lower IOP subgroups and significant reductions in both IOP and IOP-lowering medications in the higher IOP subgroups. The most common adverse events were transient IOP elevations and transient anterior chamber inflammation, which occurred with similar frequency in both groups and resolved spontaneously. CONCLUSION Goniotomy with the KDB lowered IOP significantly more than iStent implantation, with few adverse events in both groups. In eyes with mild to moderate glaucoma undergoing combined cataract extraction and glaucoma surgery, goniotomy with the KDB can safely deliver statistically significant and clinically meaningful reductions in both IOP and IOP medication burden through 12 months of follow-up. FUNDING New World Medical, Inc., provided funding for the study, medical writing assistance, Rapid Service Fees, and the open access fee.
Collapse
|
37
|
O'Reilly T, Webb A. Deconstructing and reconstructing MRI hardware. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 306:134-138. [PMID: 31311711 DOI: 10.1016/j.jmr.2019.07.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 04/28/2019] [Accepted: 07/08/2019] [Indexed: 06/10/2023]
Abstract
Three topics concerning future hardware development for clinical MRI are discussed, with the general theme of operational simplification.
Collapse
Affiliation(s)
- Thomas O'Reilly
- C.J.Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Andrew Webb
- C.J.Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands.
| |
Collapse
|
38
|
Next-generation imaging of the skeletal system and its blood supply. Nat Rev Rheumatol 2019; 15:533-549. [PMID: 31395974 DOI: 10.1038/s41584-019-0274-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/08/2019] [Indexed: 12/16/2022]
Abstract
Bone is organized in a hierarchical 3D architecture. Traditionally, analysis of the skeletal system was based on bone mass assessment by radiographic methods or on the examination of bone structure by 2D histological sections. Advanced imaging technologies and big data analysis now enable the unprecedented examination of bone and provide new insights into its 3D macrostructure and microstructure. These technologies comprise ex vivo and in vivo methods including high-resolution computed tomography (CT), synchrotron-based imaging, X-ray microscopy, ultra-high-field magnetic resonance imaging (MRI), light-sheet fluorescence microscopy, confocal and intravital two-photon imaging. In concert, these techniques have been used to detect and quantify a novel vascular system of trans-cortical vessels in bone. Furthermore, structures such as the lacunar network, which harbours and connects osteocytes, become accessible for 3D imaging and quantification using these methods. Next-generation imaging of the skeletal system and its blood supply are anticipated to contribute to an entirely new understanding of bone tissue composition and function, from macroscale to nanoscale, in health and disease. These insights could provide the basis for early detection and precision-type intervention of bone disorders in the future.
Collapse
|
39
|
Hoff MN, McKinney A, Shellock FG, Rassner U, Gilk T, Watson RE, Greenberg TD, Froelich J, Kanal E. Safety Considerations of 7-T MRI in Clinical Practice. Radiology 2019; 292:509-518. [PMID: 31310177 DOI: 10.1148/radiol.2019182742] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Although 7-T MRI has recently received approval for use in clinical patient care, there are distinct safety issues associated with this relatively high magnetic field. Forces on metallic implants and radiofrequency power deposition and heating are safety considerations at 7 T. Patient bioeffects such as vertigo, dizziness, false feelings of motion, nausea, nystagmus, magnetophosphenes, and electrogustatory effects are more common and potentially more pronounced at 7 T than at lower field strengths. Herein the authors review safety issues associated with 7-T MRI. The rationale for safety concerns at this field strength are discussed as well as potential approaches to mitigate risk to patients and health care professionals.
Collapse
Affiliation(s)
- Michael N Hoff
- From the Department of Radiology, University of Washington, 1959 NE Pacific St, Seattle, WA 98195-7117 (M.N.H.); Department of Radiology, University of Minnesota, Minneapolis, Minn (A.M., J.F.); Department of Clinical Physical Therapy, University of Southern California, Los Angeles, Calif (F.G.S.); Department of Radiology, University of Utah Health Sciences Center, Salt Lake City, Utah (U.R.); RADIOLOGY-Planning, Kansas City, Mo (T.G.); Department of Radiology, Mayo Clinic, Rochester, Minn (R.E.W.); G3 Global Group, Boulder, Colo, Mo (T.D.G.); and Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, Pa (E.K.)
| | - Alexander McKinney
- From the Department of Radiology, University of Washington, 1959 NE Pacific St, Seattle, WA 98195-7117 (M.N.H.); Department of Radiology, University of Minnesota, Minneapolis, Minn (A.M., J.F.); Department of Clinical Physical Therapy, University of Southern California, Los Angeles, Calif (F.G.S.); Department of Radiology, University of Utah Health Sciences Center, Salt Lake City, Utah (U.R.); RADIOLOGY-Planning, Kansas City, Mo (T.G.); Department of Radiology, Mayo Clinic, Rochester, Minn (R.E.W.); G3 Global Group, Boulder, Colo, Mo (T.D.G.); and Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, Pa (E.K.)
| | - Frank G Shellock
- From the Department of Radiology, University of Washington, 1959 NE Pacific St, Seattle, WA 98195-7117 (M.N.H.); Department of Radiology, University of Minnesota, Minneapolis, Minn (A.M., J.F.); Department of Clinical Physical Therapy, University of Southern California, Los Angeles, Calif (F.G.S.); Department of Radiology, University of Utah Health Sciences Center, Salt Lake City, Utah (U.R.); RADIOLOGY-Planning, Kansas City, Mo (T.G.); Department of Radiology, Mayo Clinic, Rochester, Minn (R.E.W.); G3 Global Group, Boulder, Colo, Mo (T.D.G.); and Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, Pa (E.K.)
| | - Ulrich Rassner
- From the Department of Radiology, University of Washington, 1959 NE Pacific St, Seattle, WA 98195-7117 (M.N.H.); Department of Radiology, University of Minnesota, Minneapolis, Minn (A.M., J.F.); Department of Clinical Physical Therapy, University of Southern California, Los Angeles, Calif (F.G.S.); Department of Radiology, University of Utah Health Sciences Center, Salt Lake City, Utah (U.R.); RADIOLOGY-Planning, Kansas City, Mo (T.G.); Department of Radiology, Mayo Clinic, Rochester, Minn (R.E.W.); G3 Global Group, Boulder, Colo, Mo (T.D.G.); and Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, Pa (E.K.)
| | - Tobias Gilk
- From the Department of Radiology, University of Washington, 1959 NE Pacific St, Seattle, WA 98195-7117 (M.N.H.); Department of Radiology, University of Minnesota, Minneapolis, Minn (A.M., J.F.); Department of Clinical Physical Therapy, University of Southern California, Los Angeles, Calif (F.G.S.); Department of Radiology, University of Utah Health Sciences Center, Salt Lake City, Utah (U.R.); RADIOLOGY-Planning, Kansas City, Mo (T.G.); Department of Radiology, Mayo Clinic, Rochester, Minn (R.E.W.); G3 Global Group, Boulder, Colo, Mo (T.D.G.); and Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, Pa (E.K.)
| | - Robert E Watson
- From the Department of Radiology, University of Washington, 1959 NE Pacific St, Seattle, WA 98195-7117 (M.N.H.); Department of Radiology, University of Minnesota, Minneapolis, Minn (A.M., J.F.); Department of Clinical Physical Therapy, University of Southern California, Los Angeles, Calif (F.G.S.); Department of Radiology, University of Utah Health Sciences Center, Salt Lake City, Utah (U.R.); RADIOLOGY-Planning, Kansas City, Mo (T.G.); Department of Radiology, Mayo Clinic, Rochester, Minn (R.E.W.); G3 Global Group, Boulder, Colo, Mo (T.D.G.); and Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, Pa (E.K.)
| | - Todd D Greenberg
- From the Department of Radiology, University of Washington, 1959 NE Pacific St, Seattle, WA 98195-7117 (M.N.H.); Department of Radiology, University of Minnesota, Minneapolis, Minn (A.M., J.F.); Department of Clinical Physical Therapy, University of Southern California, Los Angeles, Calif (F.G.S.); Department of Radiology, University of Utah Health Sciences Center, Salt Lake City, Utah (U.R.); RADIOLOGY-Planning, Kansas City, Mo (T.G.); Department of Radiology, Mayo Clinic, Rochester, Minn (R.E.W.); G3 Global Group, Boulder, Colo, Mo (T.D.G.); and Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, Pa (E.K.)
| | - Jerry Froelich
- From the Department of Radiology, University of Washington, 1959 NE Pacific St, Seattle, WA 98195-7117 (M.N.H.); Department of Radiology, University of Minnesota, Minneapolis, Minn (A.M., J.F.); Department of Clinical Physical Therapy, University of Southern California, Los Angeles, Calif (F.G.S.); Department of Radiology, University of Utah Health Sciences Center, Salt Lake City, Utah (U.R.); RADIOLOGY-Planning, Kansas City, Mo (T.G.); Department of Radiology, Mayo Clinic, Rochester, Minn (R.E.W.); G3 Global Group, Boulder, Colo, Mo (T.D.G.); and Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, Pa (E.K.)
| | - Emanuel Kanal
- From the Department of Radiology, University of Washington, 1959 NE Pacific St, Seattle, WA 98195-7117 (M.N.H.); Department of Radiology, University of Minnesota, Minneapolis, Minn (A.M., J.F.); Department of Clinical Physical Therapy, University of Southern California, Los Angeles, Calif (F.G.S.); Department of Radiology, University of Utah Health Sciences Center, Salt Lake City, Utah (U.R.); RADIOLOGY-Planning, Kansas City, Mo (T.G.); Department of Radiology, Mayo Clinic, Rochester, Minn (R.E.W.); G3 Global Group, Boulder, Colo, Mo (T.D.G.); and Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, Pa (E.K.)
| |
Collapse
|
40
|
Tian X, Wang D, Feng S, Zhang L, Ji X, Wang Z, Lu Q, Xi C, Pi L, Zhang X. Effects of 3.5-23.0 T static magnetic fields on mice: A safety study. Neuroimage 2019; 199:273-280. [PMID: 31158482 DOI: 10.1016/j.neuroimage.2019.05.070] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Revised: 05/03/2019] [Accepted: 05/27/2019] [Indexed: 12/19/2022] Open
Abstract
People are exposed to various magnetic fields, including the high static/steady magnetic field (SMF) of MRI, which has been increased to 9.4 T in preclinical investigations. However, relevant safety studies about high SMF are deficient. Here we examined whether 3.5-23.0 T SMF exposure for 2 h has severe long-term effects on mice using 112 C57BL/6J mice. The food/water consumption, blood glucose levels, blood routine, blood biochemistry, as well as organ weight and HE stains were all examined. The food consumption and body weight were slightly decreased for 23.0 T-exposed mice (14.6%, P < 0.01, and 1.75-5.57%, P < 0.05, respectively), but not the other groups. While total bilirubin (TBIL), white blood cells, platelet and lymphocyte numbers were affected by some magnetic conditions, most of them were still within normal reference range. Although 13.5 T magnetic fields with the highest gradient (117.2 T/m) caused spleen weight increase, the blood count and biochemistry results were still within the control reference range. Moreover, the highest field 23.0 T with no gradient did not cause organ weight or blood biochemistry abnormality, which indicates that field gradient is a key parameter. Collectively, these data suggest 3.5-23.0 T static magnetic field exposure for 2 h do not have severe long-term effects on mice.
Collapse
Affiliation(s)
- Xiaofei Tian
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China; Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui, 230601, PR China
| | - Dongmei Wang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China; Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, Anhui, 230026, PR China
| | - Shuang Feng
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China; Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, Anhui, 230026, PR China
| | - Lei Zhang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China
| | - Xinmiao Ji
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China
| | - Ze Wang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China; Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, 230026, PR China
| | - Qingyou Lu
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China; Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, 230026, PR China; Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, Hefei, Anhui, 230031, PR China
| | - Chuanying Xi
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China
| | - Li Pi
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China
| | - Xin Zhang
- High Magnetic Field Laboratory, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, 230031, PR China; Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui, 230601, PR China; Science Island Branch of Graduate School, University of Science and Technology of China, Hefei, Anhui, 230026, PR China.
| |
Collapse
|
41
|
Gach HM. Technical Note: T
1
and T
2
and complex permittivities of mineral oil, silicone oil, and glycerol at 0.35, 1.5, and 3 T. Med Phys 2019; 46:1785-1792. [DOI: 10.1002/mp.13429] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 01/23/2019] [Accepted: 01/28/2019] [Indexed: 11/11/2022] Open
Affiliation(s)
- H. Michael Gach
- Departments of Radiation Oncology, Radiology, and Biomedical Engineering Washington University in St. Louis St. Louis MO 63110 USA
| |
Collapse
|
42
|
Ladd ME, Bachert P, Meyerspeer M, Moser E, Nagel AM, Norris DG, Schmitter S, Speck O, Straub S, Zaiss M. Pros and cons of ultra-high-field MRI/MRS for human application. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2018; 109:1-50. [PMID: 30527132 DOI: 10.1016/j.pnmrs.2018.06.001] [Citation(s) in RCA: 267] [Impact Index Per Article: 44.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 06/06/2018] [Accepted: 06/07/2018] [Indexed: 05/08/2023]
Abstract
Magnetic resonance imaging and spectroscopic techniques are widely used in humans both for clinical diagnostic applications and in basic research areas such as cognitive neuroimaging. In recent years, new human MR systems have become available operating at static magnetic fields of 7 T or higher (≥300 MHz proton frequency). Imaging human-sized objects at such high frequencies presents several challenges including non-uniform radiofrequency fields, enhanced susceptibility artifacts, and higher radiofrequency energy deposition in the tissue. On the other side of the scale are gains in signal-to-noise or contrast-to-noise ratio that allow finer structures to be visualized and smaller physiological effects to be detected. This review presents an overview of some of the latest methodological developments in human ultra-high field MRI/MRS as well as associated clinical and scientific applications. Emphasis is given to techniques that particularly benefit from the changing physical characteristics at high magnetic fields, including susceptibility-weighted imaging and phase-contrast techniques, imaging with X-nuclei, MR spectroscopy, CEST imaging, as well as functional MRI. In addition, more general methodological developments such as parallel transmission and motion correction will be discussed that are required to leverage the full potential of higher magnetic fields, and an overview of relevant physiological considerations of human high magnetic field exposure is provided.
Collapse
Affiliation(s)
- Mark E Ladd
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Faculty of Medicine, University of Heidelberg, Heidelberg, Germany; Faculty of Physics and Astronomy, University of Heidelberg, Heidelberg, Germany; Erwin L. Hahn Institute for MRI, University of Duisburg-Essen, Essen, Germany.
| | - Peter Bachert
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Faculty of Physics and Astronomy, University of Heidelberg, Heidelberg, Germany.
| | - Martin Meyerspeer
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria.
| | - Ewald Moser
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria.
| | - Armin M Nagel
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Institute of Radiology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.
| | - David G Norris
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen, Nijmegen, Netherlands; Erwin L. Hahn Institute for MRI, University of Duisburg-Essen, Essen, Germany.
| | - Sebastian Schmitter
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany.
| | - Oliver Speck
- Department of Biomedical Magnetic Resonance, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; German Center for Neurodegenerative Diseases, Magdeburg, Germany; Center for Behavioural Brain Sciences, Magdeburg, Germany; Leibniz Institute for Neurobiology, Magdeburg, Germany.
| | - Sina Straub
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.
| | - Moritz Zaiss
- High-Field Magnetic Resonance Center, Max-Planck-Institute for Biological Cybernetics, Tübingen, Germany.
| |
Collapse
|
43
|
Ghosh S, Harvey P, Simon JC, Jasanoff A. Probing the brain with molecular fMRI. Curr Opin Neurobiol 2018; 50:201-210. [PMID: 29649765 DOI: 10.1016/j.conb.2018.03.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 02/12/2018] [Accepted: 03/21/2018] [Indexed: 01/07/2023]
Abstract
One of the greatest challenges of modern neuroscience is to incorporate our growing knowledge of molecular and cellular-scale physiology into integrated, organismic-scale models of brain function in behavior and cognition. Molecular-level functional magnetic resonance imaging (molecular fMRI) is a new technology that can help bridge these scales by mapping defined microscopic phenomena over large, optically inaccessible regions of the living brain. In this review, we explain how MRI-detectable imaging probes can be used to sensitize noninvasive imaging to mechanistically significant components of neural processing. We discuss how a combination of innovative probe design, advanced imaging methods, and strategies for brain delivery can make molecular fMRI an increasingly successful approach for spatiotemporally resolved studies of diverse neural phenomena, perhaps eventually in people.
Collapse
Affiliation(s)
- Souparno Ghosh
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Rm. 16-561, Cambridge, MA 02139, United States
| | - Peter Harvey
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Rm. 16-561, Cambridge, MA 02139, United States
| | - Jacob C Simon
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Rm. 16-561, Cambridge, MA 02139, United States
| | - Alan Jasanoff
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Rm. 16-561, Cambridge, MA 02139, United States; Department of Brain & Cognitive Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave., Rm. 16-561, Cambridge, MA 02139, United States; Department of Nuclear Science & Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Rm. 16-561, Cambridge, MA 02139, United States.
| |
Collapse
|
44
|
STAM R, YAMAGUCHI-SEKINO S. Occupational exposure to electromagnetic fields from medical sources. INDUSTRIAL HEALTH 2018; 56:96-105. [PMID: 29109357 PMCID: PMC5889928 DOI: 10.2486/indhealth.2017-0112] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
High exposures to electromagnetic fields (EMF) can occur near certain medical devices in the hospital environment. A systematic assessment of medical occupational EMF exposure could help to clarify where more attention to occupational safety may be needed. This paper seeks to identify sources of high exposure for hospital workers and compare the published exposure data to occupational limits in the European Union. A systematic search for peer-reviewed publications was conducted via PubMed and Scopus databases. Relevant grey literature was collected via a web search. For each publication, the highest measured magnetic flux density or internal electric field strength per device and main frequency component was extracted. For low frequency fields, high action levels may be exceeded for magnetic stimulation, MRI gradient fields and movement in MRI static fields. For radiofrequency fields, the action levels may be exceeded near devices for diathermy, electrosurgery and hyperthermia and in the radiofrequency field inside MRI scanners. The exposure limit values for internal electric field may be exceeded for MRI and magnetic stimulation. For MRI and magnetic stimulation, practical measures can limit worker exposure. For diathermy, electrosurgery and hyperthermia, additional calculations are necessary to determine if SAR limits may be exceeded in some scenarios.
Collapse
Affiliation(s)
- Rianne STAM
- National Institute for Public Health and the Environment, the Netherlands
- *To whom correspondence should be addressed. E-mail:
| | | |
Collapse
|
45
|
Abstract
We have recently witnessed an explosion of large-scale initiatives and projects addressing mapping, modeling, simulation and atlasing of the human brain, including the BRAIN Initiative, the Human Brain Project, the Human Connectome Project (HCP), the Big Brain, the Blue Brain Project, the Allen Brain Atlas, the Brainnetome, among others. Besides these large and international initiatives, there are numerous mid-size and small brain atlas-related projects. My contribution to these global efforts has been to create adult human brain atlases in health and disease, and to develop atlas-based applications. For over two decades with my R&D lab I developed 35 brain atlases, licensed to 67 companies and made available in about 100 countries. This paper has two objectives. First, it provides an overview of the state of the art in brain atlasing. Second, as it is already 20 years from the release of our first brain atlas, I summarise my past and present efforts, share my experience in atlas creation, validation and commercialisation, compare with the state of the art, and propose future directions.
Collapse
Affiliation(s)
- Wieslaw L Nowinski
- John Paull II Center for Virtual Anatomy and Surgical Simulation, University of Cardinal Stefan Wyszynski in Warsaw, Poland
| |
Collapse
|
46
|
Abstract
OBJECTIVE Outline effects of functional neuroimaging on neuropsychology over the past 25 years. METHOD Functional neuroimaging methods and studies will be described that provide a historical context, offer examples of the utility of neuroimaging in specific domains, and discuss the limitations and future directions of neuroimaging in neuropsychology. RESULTS Tracking the history of publications on functional neuroimaging related to neuropsychology indicates early involvement of neuropsychologists in the development of these methodologies. Initial progress in neuropsychological application of functional neuroimaging has been hampered by costs and the exposure to ionizing radiation. With rapid evolution of functional methods-in particular functional MRI (fMRI)-neuroimaging has profoundly transformed our knowledge of the brain. Its current applications span the spectrum of normative development to clinical applications. The field is moving toward applying sophisticated statistical approaches that will help elucidate distinct neural activation networks associated with specific behavioral domains. The impact of functional neuroimaging on clinical neuropsychology is more circumscribed, but the prospects remain enticing. CONCLUSIONS The theoretical insights and empirical findings of functional neuroimaging have been led by many neuropsychologists and have transformed the field of behavioral neuroscience. Thus far they have had limited effects on the clinical practices of neuropsychologists. Perhaps it is time to add training in functional neuroimaging to the clinical neuropsychologist's toolkit and from there to the clinic or bedside. (PsycINFO Database Record
Collapse
Affiliation(s)
- David R. Roalf
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine Philadelphia, Philadelphia, PA, 19104
| | - Ruben C. Gur
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine Philadelphia, Philadelphia, PA, 19104
- Lifespan Brain Institute (LiBI) at the University of Pennsylvania and Children’s Hospital of Philadelphia, Philadelphia, PA, 19104, USA
| |
Collapse
|
47
|
Zaretskaya N, Fischl B, Reuter M, Renvall V, Polimeni JR. Advantages of cortical surface reconstruction using submillimeter 7 T MEMPRAGE. Neuroimage 2017; 165:11-26. [PMID: 28970143 DOI: 10.1016/j.neuroimage.2017.09.060] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 09/09/2017] [Accepted: 09/28/2017] [Indexed: 12/13/2022] Open
Abstract
Recent advances in MR technology have enabled increased spatial resolution for routine functional and anatomical imaging, which has created demand for software tools that are able to process these data. The availability of high-resolution data also raises the question of whether higher resolution leads to substantial gains in accuracy of quantitative morphometric neuroimaging procedures, in particular the cortical surface reconstruction and cortical thickness estimation. In this study we adapted the FreeSurfer cortical surface reconstruction pipeline to process structural data at native submillimeter resolution. We then quantified the differences in surface placement between meshes generated from (0.75 mm)3 isotropic resolution data acquired in 39 volunteers and the same data downsampled to the conventional 1 mm3 voxel size. We find that when processed at native resolution, cortex is estimated to be thinner in most areas, but thicker around the Cingulate and the Calcarine sulci as well as in the posterior bank of the Central sulcus. Thickness differences are driven by two kinds of effects. First, the gray-white surface is found closer to the white matter, especially in cortical areas with high myelin content, and thus low contrast, such as the Calcarine and the Central sulci, causing local increases in thickness estimates. Second, the gray-CSF surface is placed more interiorly, especially in the deep sulci, contributing to local decreases in thickness estimates. We suggest that both effects are due to reduced partial volume effects at higher spatial resolution. Submillimeter voxel sizes can therefore provide improved accuracy for measuring cortical thickness.
Collapse
Affiliation(s)
- Natalia Zaretskaya
- Centre for Integrative Neuroscience, University of Tuebingen, Tuebingen, Germany; Department of Psychology, University of Tübingen, Tübingen, Germany; Max Planck Institute for Biological Cybernetics, Tübingen, Germany; Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA.
| | - Bruce Fischl
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Radiology, Harvard Medical School, Boston, MA, USA; Computer Science and AI Lab (CSAIL), Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Martin Reuter
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Radiology, Harvard Medical School, Boston, MA, USA; Computer Science and AI Lab (CSAIL), Massachusetts Institute of Technology, Cambridge, MA, USA; German Center for Neurodegenerative Diseases, DZNE, Bonn, Germany
| | - Ville Renvall
- Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, Espoo, Finland
| | - Jonathan R Polimeni
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Radiology, Harvard Medical School, Boston, MA, USA; Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, USA
| |
Collapse
|
48
|
Fatahi M, Reddig A, Friebe B, Reinhold D, Speck O. MRI and Genetic Damage: An Update. CURRENT RADIOLOGY REPORTS 2017. [DOI: 10.1007/s40134-017-0216-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
|