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Oshiro H, Hata J, Nakashima D, Hayashi N, Haga Y, Hagiya K, Yoshimaru D, Okano H. Influence of Diffusion Time and Temperature on Restricted Diffusion Signal: A Phantom Study. Magn Reson Med Sci 2024; 23:136-145. [PMID: 36754420 PMCID: PMC11024708 DOI: 10.2463/mrms.mp.2022-0103] [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: 08/16/2022] [Accepted: 12/17/2022] [Indexed: 02/10/2023] Open
Abstract
PURPOSE Diffusion MRI is a physical measurement method that quantitatively indicates the displacement of water molecules diffusing in voxels. However, there are insufficient data to characterize the diffusion process physically in a uniform structure such as a phantom. This study investigated the transitional relationship between structure scale, temperature, and diffusion time for simple restricted diffusion using a capillary phantom. METHODS We performed diffusion-weighted pulsed-gradient stimulated-echo acquisition mode (STEAM) MRI with a 9.4 Tesla MRI system (Bruker BioSpin, Ettlingen, Germany) and a quadrature coil with an inner diameter of 86 mm (Bruker BioSpin). We measured the diffusion coefficients (radial diffusivity [RD]) of capillary plates (pore sizes 6, 12, 25, 50, and 100 μm) with uniformly restricted structures at various temperatures (10ºC, 20ºC, 30ºC, and 40ºC) and multiple diffusion times (12-800 ms). We evaluated the characteristics of scale, temperature, and diffusion time for restricted diffusion. RESULTS The RD decayed and became constant depending on the structural scale. Diffusion coefficient fluctuations with temperature occurred mostly under conditions of a large structural scale and short diffusion time. We obtained data suggesting that temperature-dependent changes in the diffusion coefficients follow physical laws. CONCLUSION No water molecules were observed outside the glass tubes in the capillary plates, and the capillary plates only reflected a restricted diffusion process within the structure.We experimentally evaluated the characteristics of simple restricted diffusion to reveal the transitional relationship of the diffusion coefficient with diffusion time, structure scale, and temperature through composite measurement.
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Affiliation(s)
- Hinako Oshiro
- Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
- Center for Brain Science, RIKEN, Wako, Saitama, Japan
| | - Junichi Hata
- Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
- Center for Brain Science, RIKEN, Wako, Saitama, Japan
- School of Medicine, Keio University, Tokyo, Japan
- Division of Regenerative Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | | | - Naoya Hayashi
- Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
- Center for Brain Science, RIKEN, Wako, Saitama, Japan
| | - Yawara Haga
- Graduate School of Human Health Sciences, Tokyo Metropolitan University, Tokyo, Japan
- Center for Brain Science, RIKEN, Wako, Saitama, Japan
| | - Kei Hagiya
- Center for Brain Science, RIKEN, Wako, Saitama, Japan
| | - Daisuke Yoshimaru
- Center for Brain Science, RIKEN, Wako, Saitama, Japan
- School of Medicine, Keio University, Tokyo, Japan
- Division of Regenerative Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Hideyuki Okano
- Center for Brain Science, RIKEN, Wako, Saitama, Japan
- School of Medicine, Keio University, Tokyo, Japan
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Bashir A, Khan S, Bashmal S, Iqbal N, Ullah S, Ali L. Designing Highly Efficient Temperature Controller for Nanoparticles Hyperthermia. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3539. [PMID: 36234672 PMCID: PMC9565335 DOI: 10.3390/nano12193539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 10/02/2022] [Accepted: 10/04/2022] [Indexed: 06/16/2023]
Abstract
This paper presents various control system design techniques for temperature control of Magnetic Fluid hyperthermia. The purpose of this research is to design a cost-effective, efficient, and practically implementable temperature controller for Magnetic Fluid hyperthermia, which is presently under research as a substitute to the radiation and chemotherapy treatment of cancer. The principle of this phenomenon centers on the greater sensitivity of tumor cells to changes in temperature in comparison to healthy cells. Once the nanoparticles reach the desired tissue, it can then be placed in a varying magnetic field to dissipate the heat locally by raising the temperature to 45 °C in order to kill cancerous cells. One of the challenging tasks is to maintain the temperature strictly at desired point i.e., 45 °C. Temperature controller for magnetic fluid hyperthermia provides the tight control of temperature in order to avoid folding of proteins and save the tissues around the cancerous tissue from getting destroyed. In contrast with most of the existing research on this topic, which are based on linear control strategies or their improved versions, the novelty of this research lies in applying nonlinear control technique like Sliding Mode Control (SMC) to accurately control the temperature at desired value. A comparison of the control techniques is presented in this paper, based on reliability, robustness, precision and the ability of the controller to handle the non-linearities that are faced during the treatment of cancer. SMC showed promising results in terms of settling time and rise time. Steady state error was also reduced to zero using this technique.
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Affiliation(s)
- Adeel Bashir
- Department of Electrical Engineering, COMSATS University, Islamabad 45550, Pakistan
| | - Sikandar Khan
- Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Salem Bashmal
- Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
- Interdisciplinary Research Center for Intelligent Manufacturing and Robotics, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Naveed Iqbal
- Department of Electrical Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
- Center of Energy and Geo Processing, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Sami Ullah
- K. A. CARE Energy Research & Innovation Center (ERIC), King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Liaqat Ali
- College of Civil Engineering & Architecture, Zhejiang University, Hangzhou 310058, China
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Shibukawa S, Niwa T, Miyati T, Ogino T, Yoshimaru D, Kuroda K. Temperature measurement of intracranial cerebrospinal fluid using second-order motion compensation diffusion tensor imaging. Phys Med Biol 2021; 66. [PMID: 34874287 DOI: 10.1088/1361-6560/ac3fff] [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: 08/29/2021] [Accepted: 12/03/2021] [Indexed: 11/12/2022]
Abstract
To reduce the determination errors of CSF pulsation in diffusion-weighted image (DWI) thermometry, we investigated whether applying second-order motion compensation diffusion tensor imaging (2nd-MC DTI) and fractional anisotropy (FA) processing improves the measurement of intracranial cerebrospinal fluid (CSF) temperature. In a phantom study, we investigated the relationship between temperature and FA in artificial CSF (ACSF) to determine the threshold for FA processing. The calculated temperatures of ACSF were compared with those of water. In a human study, 18 healthy volunteers were scanned using conventional DTI (c-DTI) and 2nd-MC DTI on a 3.0 T magnetic resonance imaging (MRI) system. A temperature map was created using diffusion coefficients from each DWI with/without FA processing. The temperatures of intracranial CSF were compared between each DTI image using Welch's analysis of variance and Games-Howell's multiple comparisons. In the phantom study, FA did not exceed 0.1 at any temperature. Consequently, pixels exceeding the threshold of 0.1 were removed from the temperature map. Intracranial CSF temperatures significantly differed between the four methods (p < 0.0001). The lowest temperature was 2nd-MC DTI with FA processing (mean, 35.62 °C), followed in order by c-DTI with FA processing (mean, 36.16 °C), 2nd-MC DTI (mean, 37.08 °C), and c-DTI (mean, 39.08 °C;p < 0.01 for each). Because the calculated temperature of ACSF was estimated to be lower than that of water, the temperature of 2nd-DTI with FA processing was considered reasonable. The method of 2nd-MC DTI with FA processing enabled determining intracranial CSF temperature with a reduction in CSF pulsation.
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Affiliation(s)
- Shuhei Shibukawa
- Department of Radiological Technology, Faculty of Health Science, Juntendo University, Bunkyo-Ku, Tokyo, Japan.,Department of Radiology, Tokai University School of Medicine, Isehara, Kanagawa, Japan.,Center for Evolutionary Cognitive Sciences, Graduate School of Art and Sciences, The University of Tokyo, Meguro-ku, Tokyo, Japan.,Department of Radiology, Tokyo Medical University, Shinjuku-ku, Tokyo, Japan
| | - Tetsu Niwa
- Department of Radiology, Tokai University School of Medicine, Isehara, Kanagawa, Japan
| | - Tosiaki Miyati
- Division of Health Sciences, Graduate School of Medical Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan
| | - Tetsuo Ogino
- Philips Japan, Healthcare, Shinagawa, Tokyo, Japan
| | - Daisuke Yoshimaru
- Department of Radiology, Tokyo Medical University, Shinjuku-ku, Tokyo, Japan.,Division of Regenerative Medicine, Jikei University School of Medicine, Tokyo, Japan
| | - Kagayaki Kuroda
- Course of Electrical and Electronic Engineering, Graduate School of Engineering, Tokai University, Kanagawa, Japan
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Payne A, Chopra R, Ellens N, Chen L, Ghanouni P, Sammet S, Diederich C, Ter Haar G, Parker D, Moonen C, Stafford J, Moros E, Schlesinger D, Benedict S, Wear K, Partanen A, Farahani K. AAPM Task Group 241: A medical physicist's guide to MRI-guided focused ultrasound body systems. Med Phys 2021; 48:e772-e806. [PMID: 34224149 DOI: 10.1002/mp.15076] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 04/28/2021] [Accepted: 06/21/2021] [Indexed: 11/07/2022] Open
Abstract
Magnetic resonance-guided focused ultrasound (MRgFUS) is a completely non-invasive technology that has been approved by FDA to treat several diseases. This report, prepared by the American Association of Physicist in Medicine (AAPM) Task Group 241, provides background on MRgFUS technology with a focus on clinical body MRgFUS systems. The report addresses the issues of interest to the medical physics community, specific to the body MRgFUS system configuration, and provides recommendations on how to successfully implement and maintain a clinical MRgFUS program. The following sections describe the key features of typical MRgFUS systems and clinical workflow and provide key points and best practices for the medical physicist. Commonly used terms, metrics and physics are defined and sources of uncertainty that affect MRgFUS procedures are described. Finally, safety and quality assurance procedures are explained, the recommended role of the medical physicist in MRgFUS procedures is described, and regulatory requirements for planning clinical trials are detailed. Although this report is limited in scope to clinical body MRgFUS systems that are approved or currently undergoing clinical trials in the United States, much of the material presented is also applicable to systems designed for other applications.
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Affiliation(s)
- Allison Payne
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | - Rajiv Chopra
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX, USA
| | | | - Lili Chen
- Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA
| | - Pejman Ghanouni
- Department of Radiology, Stanford University, Stanford, CA, USA
| | - Steffen Sammet
- Department of Radiology, University of Chicago, Chicago, IL, USA
| | - Chris Diederich
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, USA
| | | | - Dennis Parker
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | - Chrit Moonen
- Imaging Division, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jason Stafford
- Department of Imaging Physics, MD Anderson Cancer Center, Houston, TX, USA
| | - Eduardo Moros
- Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL, USA
| | - David Schlesinger
- Department of Radiation Oncology, University of Virginia, Charlottesville, VA, USA
| | | | - Keith Wear
- U.S. Food and Drug Administration, Silver Spring, MD, USA
| | | | - Keyvan Farahani
- National Cancer Institute, National Institutes of Health, Rockville, MD, USA
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Adibzadeh F, Sumser K, Curto S, Yeo DTB, Shishegar AA, Paulides MM. Systematic review of pre-clinical and clinical devices for magnetic resonance-guided radiofrequency hyperthermia. Int J Hyperthermia 2020; 37:15-27. [PMID: 31918599 DOI: 10.1080/02656736.2019.1705404] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Clinical trials have demonstrated the therapeutic benefits of adding radiofrequency (RF) hyperthermia (HT) as an adjuvant to radio- and chemotherapy. However, maximum utilization of these benefits is hampered by the current inability to maintain the temperature within the desired range. RF HT treatment quality is usually monitored by invasive temperature sensors, which provide limited data sampling and are prone to infection risks. Magnetic resonance (MR) temperature imaging has been developed to overcome these hurdles by allowing noninvasive 3D temperature monitoring in the target and normal tissues. To exploit this feature, several approaches for inserting the RF heating devices into the MR scanner have been proposed over the years. In this review, we summarize the status quo in MR-guided RF HT devices and analyze trends in these hybrid hardware configurations. In addition, we discuss the various approaches, extract best practices and identify gaps regarding the experimental validation procedures for MR - RF HT, aimed at converging to a common standard in this process.
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Affiliation(s)
- Fatemeh Adibzadeh
- Department of Radiation Oncology, Erasmus MC - Cancer Institute, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Department of Electrical Engineering, Technical University of Sharif, Tehran, Iran
| | - Kemal Sumser
- Department of Radiation Oncology, Erasmus MC - Cancer Institute, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Sergio Curto
- Department of Radiation Oncology, Erasmus MC - Cancer Institute, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | | | - Amir A Shishegar
- Department of Electrical Engineering, Technical University of Sharif, Tehran, Iran
| | - Margarethus M Paulides
- Department of Radiation Oncology, Erasmus MC - Cancer Institute, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Department of Electrical Engineering, Technical University of Eindhoven, Eindhoven, The Netherlands
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6
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Zhang Z, Wu HH, Priester A, Magyar C, Afshari Mirak S, Shakeri S, Mohammadian Bajgiran A, Hosseiny M, Azadikhah A, Sung K, Reiter RE, Sisk AE, Raman S, Enzmann DR. Prostate Microstructure in Prostate Cancer Using 3-T MRI with Diffusion-Relaxation Correlation Spectrum Imaging: Validation with Whole-Mount Digital Histopathology. Radiology 2020; 296:348-355. [PMID: 32515678 DOI: 10.1148/radiol.2020192330] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Background Microstructural MRI has the potential to improve diagnosis and characterization of prostate cancer (PCa), but validation with histopathology is lacking. Purpose To validate ex vivo diffusion-relaxation correlation spectrum imaging (DR-CSI) in the characterization of microstructural tissue compartments in prostate specimens from men with PCa by using registered whole-mount digital histopathology (WMHP) as the reference standard. Materials and Methods Men with PCa who underwent 3-T MRI and robotic-assisted radical prostatectomy between June 2018 and January 2019 were prospectively studied. After prostatectomy, the fresh whole prostate specimens were imaged in patient-specific three-dimensionally printed molds by using 3-T MRI with DR-CSI and were then sliced to create coregistered WMHP slides. The DR-CSI spectral signal component fractions (fA, fB, fC) were compared with epithelial, stromal, and luminal area fractions (fepithelium, fstroma, flumen) quantified in PCa and benign tissue regions. A linear mixed-effects model assessed the correlations between (fA, fB, fC) and (fepithelium, fstroma, flumen), and the strength of correlations was evaluated by using Spearman correlation coefficients. Differences between PCa and benign tissues in terms of DR-CSI signal components and microscopic tissue compartments were assessed using two-sided t tests. Results Prostate specimens from nine men (mean age, 65 years ± 7 [standard deviation]) were evaluated; 20 regions from 17 PCas, along with 20 benign tissue regions of interest, were analyzed. Three DR-CSI spectral signal components (spectral peaks) were consistently identified. The fA, fB, and fC were correlated with fepithelium, fstroma, and flumen (all P < .001), with Spearman correlation coefficients of 0.74 (95% confidence interval [CI]: 0.62, 0.83), 0.80 (95% CI: 0.66, 0.89), and 0.67 (95% CI: 0.51, 0.81), respectively. PCa exhibited differences compared with benign tissues in terms of increased fA (PCa vs benign, 0.37 ± 0.05 vs 0.27 ± 0.06; P < .001), decreased fC (PCa vs benign, 0.18 ± 0.06 vs 0.31 ± 0.13; P = .01), increased fepithelium (PCa vs benign, 0.44 ± 0.13 vs 0.26 ± 0.16; P < .001), and decreased flumen (PCa vs benign, 0.14 ± 0.08 vs 0.27 ± 0.18; P = .004). Conclusion Diffusion-relaxation correlation spectrum imaging signal components correlate with microscopic tissue compartments in the prostate and differ between cancer and benign tissue. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Lee and Hectors in this issue.
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Affiliation(s)
- Zhaohuan Zhang
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
| | - Holden H Wu
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
| | - Alan Priester
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
| | - Clara Magyar
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
| | - Sohrab Afshari Mirak
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
| | - Sepideh Shakeri
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
| | - Amirhossein Mohammadian Bajgiran
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
| | - Melina Hosseiny
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
| | - Afshin Azadikhah
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
| | - Kyunghyun Sung
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
| | - Robert E Reiter
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
| | - Anthony E Sisk
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
| | - Steven Raman
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
| | - Dieter R Enzmann
- From the Department of Radiological Sciences, David Geffen School of Medicine (Z.Z., H.H.W., S.A.M., S.S., A.M.B., M.H., A.A., K.S., S.R., D.R.E.), Department of Bioengineering (Z.Z., H.H.W.), Department of Urology (A.P., R.E.R.), and Department of Pathology and Laboratory Medicine (C.M., A.E.S.), University of California, Los Angeles, 300 UCLA Medical Plaza, Suite B119, Los Angeles, CA 90095
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Optimal strategy for measuring intraventricular temperature using acceleration motion compensation diffusion-weighted imaging. Radiol Phys Technol 2020; 13:136-143. [DOI: 10.1007/s12194-020-00560-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 03/03/2020] [Accepted: 03/05/2020] [Indexed: 10/24/2022]
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8
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Paulides M, Dobsicek Trefna H, Curto S, Rodrigues D. Recent technological advancements in radiofrequency- andmicrowave-mediated hyperthermia for enhancing drug delivery. Adv Drug Deliv Rev 2020; 163-164:3-18. [PMID: 32229271 DOI: 10.1016/j.addr.2020.03.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 03/20/2020] [Accepted: 03/24/2020] [Indexed: 12/23/2022]
Abstract
Hyperthermia therapy is a potent enhancer of chemotherapy and radiotherapy. In particular, microwave (MW) and radiofrequency (RF) hyperthermia devices provide a variety of heating approaches that can treat most cancers regardless the size. This review introduces the physics of MW/RF hyperthermia, the current state-of-the-art systems for both localized and regional heating, and recent advancements in hyperthermia treatment guidance using real-time computational simulations and magnetic resonance thermometry. Clinical trials involving RF/MW hyperthermia as adjuvant for chemotherapy are also presented per anatomical site. These studies favor the use of adjuvant hyperthermia since it significantly improves curative and palliative clinical outcomes. The main challenge of hyperthermia is the distribution of state-of-the-art heating systems. Nevertheless, we anticipate that recent technology advances will expand the use of hyperthermia to chemotherapy centers for enhanced drug delivery. These new technologies hold great promise not only for (image-guided) perfusion modulation and sensitization for cytotoxic drugs, but also for local delivery of various compounds using thermosensitive liposomes.
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Romero JA, Rodriguez GG, Anoardo E. A fast field-cycling MRI relaxometer for physical contrasts design and pre-clinical studies in small animals. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2020; 311:106682. [PMID: 31923764 DOI: 10.1016/j.jmr.2019.106682] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 12/28/2019] [Accepted: 12/29/2019] [Indexed: 06/10/2023]
Abstract
We present a fast field-cycling NMR relaxometer with added magnetic resonance imaging capabilities. The instrument operates at a maximum proton Larmor frequency of 5 MHz for a sample volume of 35 mL. The magnetic field homogeneity across the sample is 1400 ppm. The main field is generated with a notch-coil electromagnet of own design, fed with a current whose stability is 220 ppm. We show that images of reasonable quality can still be produced under such conditions. The machine is being designed for concept testing of the involved instrumentation and specific contrast agents aimed for field-cycling magnetic resonance imaging applications. The general performance of the prototype was tested through localized relaxometry experiments, T1-dispersion weighted images, temperature maps and T1-weighted images at different magnetic field intensities. We introduce the concept of positive and negative contrast depending on the use of pre-polarized or non-polarized sequences. The system is being improved for pre-clinical studies in small animals.
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Affiliation(s)
- Javier A Romero
- Laboratorio de Relaxometría y Técnicas Especiales (LaRTE), Grupo de Resonancia Magnética Nuclear, FaMAF, Universidad Nacional de Córdoba e IFEG-CONICET, Córdoba, Argentina
| | - Gonzalo G Rodriguez
- Laboratorio de Relaxometría y Técnicas Especiales (LaRTE), Grupo de Resonancia Magnética Nuclear, FaMAF, Universidad Nacional de Córdoba e IFEG-CONICET, Córdoba, Argentina
| | - Esteban Anoardo
- Laboratorio de Relaxometría y Técnicas Especiales (LaRTE), Grupo de Resonancia Magnética Nuclear, FaMAF, Universidad Nacional de Córdoba e IFEG-CONICET, Córdoba, Argentina.
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Silletta EV, Jerschow A, Madelin G, Alon L. Multinuclear absolute magnetic resonance thermometry. COMMUNICATIONS PHYSICS 2019; 2:152. [PMID: 33072888 PMCID: PMC7561043 DOI: 10.1038/s42005-019-0252-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 10/29/2019] [Indexed: 06/11/2023]
Abstract
Non-invasive measurement of absolute temperature is important for proper characterization of various pathologies and for evaluation of thermal dose during interventional procedures. The proton (hydrogen nucleus) magnetic resonance (MR) frequency shift method can be used to map relative temperature changes. However, spatiotemporal variations in the main magnetic field and the lack of local internal frequency reference challenge the determination of absolute temperature. Here, we introduce a multinuclear method for absolute MR thermometry, based on the fact that the hydrogen and sodium nuclei exhibit a unique and distinct characteristic frequency dependence with temperature and with electrolyte concentration. A one-to-one mapping between the precession frequency difference of the two nuclei and absolute temperature is demonstrated. Proof-of-concept experiments were conducted in aqueous solutions with different NaCl concentrations, in agarose gel samples, and in freshly excised ex vivo mouse tissues. One-dimensional chemical shift imaging experiments also demonstrated excellent agreement with infrared measurements.
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Affiliation(s)
- Emilia V. Silletta
- New York University, Department of Chemistry, 100 Washington Square E, New York, NY 10003, USA
- Universidad Nacional de Córdoba, Facultad de Matemática, Astronomía, Física y Computación, Medina Allende s/n, X5000HUA Córdoba, Argentina
- Instituto de Física Enrique Gaviola, CONICET, Medina Allende s/n, X5000HUA Córdoba, Argentina
| | - Alexej Jerschow
- New York University, Department of Chemistry, 100 Washington Square E, New York, NY 10003, USA
| | - Guillaume Madelin
- New York University School of Medicine, Department of Radiology, Center for Biomedical Imaging, 660 First Avenue, New York, NY 10016, USA
| | - Leeor Alon
- New York University School of Medicine, Department of Radiology, Center for Biomedical Imaging, 660 First Avenue, New York, NY 10016, USA
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Odéen H, Parker DL. Magnetic resonance thermometry and its biological applications - Physical principles and practical considerations. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2019; 110:34-61. [PMID: 30803693 PMCID: PMC6662927 DOI: 10.1016/j.pnmrs.2019.01.003] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 01/23/2019] [Indexed: 05/25/2023]
Abstract
Most parameters that influence the magnetic resonance imaging (MRI) signal experience a temperature dependence. The fact that MRI can be used for non-invasive measurements of temperature and temperature change deep inside the human body has been known for over 30 years. Today, MR temperature imaging is widely used to monitor and evaluate thermal therapies such as radio frequency, microwave, laser, and focused ultrasound therapy. In this paper we cover the physical principles underlying the biological applications of MR temperature imaging and discuss practical considerations and remaining challenges. For biological tissue, the MR signal of interest comes mostly from hydrogen protons of water molecules but also from protons in, e.g., adipose tissue and various metabolites. Most of the discussed methods, such as those using the proton resonance frequency (PRF) shift, T1, T2, and diffusion only measure temperature change, but measurements of absolute temperatures are also possible using spectroscopic imaging methods (taking advantage of various metabolite signals as internal references) or various types of contrast agents. Currently, the PRF method is the most used clinically due to good sensitivity, excellent linearity with temperature, and because it is largely independent of tissue type. Because the PRF method does not work in adipose tissues, T1- and T2-based methods have recently gained interest for monitoring temperature change in areas with high fat content such as the breast and abdomen. Absolute temperature measurement methods using spectroscopic imaging and contrast agents often offer too low spatial and temporal resolution for accurate monitoring of ablative thermal procedures, but have shown great promise in monitoring the slower and usually less spatially localized temperature change observed during hyperthermia procedures. Much of the current research effort for ablative procedures is aimed at providing faster measurements, larger field-of-view coverage, simultaneous monitoring in aqueous and adipose tissues, and more motion-insensitive acquisitions for better precision measurements in organs such as the heart, liver, and kidneys. For hyperthermia applications, larger coverage, motion insensitivity, and simultaneous aqueous and adipose monitoring are also important, but great effort is also aimed at solving the problem of long-term field drift which gets interpreted as temperature change when using the PRF method.
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Affiliation(s)
- Henrik Odéen
- University of Utah, Utah Center for Advanced Imaging Research, Department of Radiology and Imaging Sciences, 729 Arapeen Drive, Salt Lake City, UT 84108-1217, USA.
| | - Dennis L Parker
- University of Utah, Utah Center for Advanced Imaging Research, Department of Radiology and Imaging Sciences, 729 Arapeen Drive, Salt Lake City, UT 84108-1217, USA.
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Warach S. Review : Mapping Brain Pathophysiology and Higher Cortical Function with Magnetic Resonance Imaging. Neuroscientist 2016. [DOI: 10.1177/107385849500100406] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Advances in magnetic resonance imaging (MRI) have moved the technology beyond its application solely as a diagnostic test to become a tool for addressing questions of in vivo pathophysiology and higher cortical function in humans. Diffusion-weighted MRI measures the apparent rate of translational movement of water molecules through brain parenchyma. This measurement can be used to determine axonal orientation within white matter, to define regions of tissue edema, and to permit early identification of ischemic neuronal injury related to impairment of Na+-K +-ATPase activity in experimental and human stroke. Changes in various aspects of cerebral perfusion—blood volume, blood flow, and hemoglobin oxygen saturation—can be mea sured with MRI, and altered cerebrovascular circulation and regional brain activation can thereby be inves tigated. Echo planar imaging is a method of ultrafast data acquisition with MRI—individual images are ac quired on the order of 100 msec. Echo planar imaging makes diffusion and perfusion measurements more practicable for diverse applications and allows for the study of temporal characteristics of regional brain responses to stimuli. Diffusion and perfusion MRI, generally termed functional MRI, are tools for studying in vivo brain physiology with MRI and are being applied to a broad range of questions in neuroscience. The Neuroscientist 1:221-235, 1995
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Affiliation(s)
- Steven Warach
- Departments of Neurology and Radiology Harvard Medical
School Beth Israel Hospital Boston, Massachusetts
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Deep Into the Fibers! Postmortem Diffusion Tensor Imaging in Forensic Radiology. Am J Forensic Med Pathol 2015; 36:153-61. [DOI: 10.1097/paf.0000000000000177] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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KURIYAMA N, YAMADA K, SAKAI K, TOKUDA T, AKAZAWA K, TOMII Y, TAMURA A, KONDO M, WATANABE I, OZAKI E, MATSUI D, NAKAGAWA M, MIZUNO T, WATANABE Y. Ventricular Temperatures in Idiopathic Normal Pressure Hydrocephalus (iNPH) Measured with DWI-based MR Thermometry. Magn Reson Med Sci 2015; 14:305-12. [DOI: 10.2463/mrms.2014-0076] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Nagato KURIYAMA
- Department of Epidemiology for Community Health and Medicine, Kyoto Prefectural University of Medicine
- Department of Neurology, Kyoto Prefectural University of Medicine
| | - Kei YAMADA
- Department of Radiology, Kyoto Prefectural University of Medicine
| | - Koji SAKAI
- Graduate School of Medicine, Kyoto University
| | - Takahiko TOKUDA
- Department of Neurology, Kyoto Prefectural University of Medicine
| | - Kentaro AKAZAWA
- Department of Radiology, Kyoto Prefectural University of Medicine
| | - Yasuhiro TOMII
- Department of Neurology, Kyoto Prefectural University of Medicine
| | - Aiko TAMURA
- Department of Neurology, Kyoto Prefectural University of Medicine
| | - Masaki KONDO
- Department of Neurology, Kyoto Prefectural University of Medicine
| | - Isao WATANABE
- Department of Epidemiology for Community Health and Medicine, Kyoto Prefectural University of Medicine
| | - Etsuko OZAKI
- Department of Epidemiology for Community Health and Medicine, Kyoto Prefectural University of Medicine
| | - Daisuke MATSUI
- Department of Epidemiology for Community Health and Medicine, Kyoto Prefectural University of Medicine
| | | | - Toshiki MIZUNO
- Department of Neurology, Kyoto Prefectural University of Medicine
| | - Yoshiyuki WATANABE
- Department of Epidemiology for Community Health and Medicine, Kyoto Prefectural University of Medicine
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Cavallo Marincola B, Pediconi F, Anzidei M, Miglio E, Di Mare L, Telesca M, Mancini M, D’Amati G, Monti M, Catalano C, Napoli A. High-intensity focused ultrasound in breast pathology: non-invasive treatment of benign and malignant lesions. Expert Rev Med Devices 2014; 12:191-9. [DOI: 10.1586/17434440.2015.986096] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Kwon OI, Chauhan M, Kim HJ, Jeong WC, Wi H, Oh TI, Woo EJ. Fast conductivity imaging in magnetic resonance electrical impedance tomography (MREIT) for RF ablation monitoring. Int J Hyperthermia 2014; 30:447-55. [PMID: 25329351 DOI: 10.3109/02656736.2014.966337] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
PURPOSE This study shows the potential of magnetic resonance electrical impedance tomography (MREIT) as a non-invasive RF ablation monitoring technique. MATERIALS AND METHODS We prepared bovine muscle tissue with a pair of needle electrodes for RF ablation, a temperature sensor, and two pairs of surface electrodes for conductivity image reconstructions. We used the injected current non-linear encoding with multi-echo gradient recalled echo (ICNE-MGRE) pulse sequence in a series of MREIT scans for conductivity imaging. We acquired magnetic flux density data induced by externally injected currents, while suppressing other phase artefacts. We used an 8-channel RF head coil and 8 echoes to improve the signal-to-noise ratio (SNR) in measured magnetic flux density data. Using the measured data, we reconstructed a time series of 180 conductivity images at every 10.24 s during and after RF ablation. RESULTS Tissue conductivity values in the lesion increased with temperature during RF ablation. After reaching 60 °C, a steep increase in tissue conductivity values occurred with relatively little temperature increase. After RF ablation, tissue conductivity values in the lesion decreased with temperature, but to values different from those before ablation due to permanent structural changes of tissue by RF ablation. CONCLUSION We could monitor temperature and also structural changes in tissue during RF ablation by producing spatio-temporal maps of tissue conductivity values using a fast MREIT conductivity imaging method. We expect that the new monitoring method could be used to estimate lesions during RF ablation and improve the efficacy of the treatment.
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Affiliation(s)
- Oh In Kwon
- Department of Mathematics, Konkuk University , Seoul , Korea and
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Galea N, Cantisani V, Taouli B. Liver lesion detection and characterization: role of diffusion-weighted imaging. J Magn Reson Imaging 2014; 37:1260-76. [PMID: 23712841 DOI: 10.1002/jmri.23947] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 10/11/2012] [Indexed: 12/11/2022] Open
Abstract
Diffusion-weighted imaging (DWI) plays an emerging role for the assessment of focal and diffuse liver diseases. This growing interest is due to that fact that DWI is a noncontrast technique with inherent high contrast resolution, with promising results for detection and characterization of focal liver lesions. Recent advances in diffusion image quality have also added interest to this technique in the abdomen. The purpose of this review is to describe the current clinical roles of DWI for the detection and characterization of focal liver lesions, and to review pitfalls, limitations, and future directions of DWI for assessment of focal liver disease.
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Affiliation(s)
- Nicola Galea
- Sapienza University of Rome, Department of Radiological Sciences, Rome, Italy
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18
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Oh TI, Kim HJ, Jeong WC, Chauhan M, Kwon OI, Woo EJ. Detection of temperature distribution via recovering electrical conductivity in MREIT. Phys Med Biol 2013; 58:2697-711. [DOI: 10.1088/0031-9155/58/8/2697] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Bouhrara M, Lehallier B, Clerjon S, Damez JL, Bonny JM. Mapping of muscle deformation during heating: in situ dynamic MRI and nonlinear registration. Magn Reson Imaging 2012; 30:422-30. [DOI: 10.1016/j.mri.2011.10.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Revised: 09/23/2011] [Accepted: 10/06/2011] [Indexed: 12/31/2022]
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Korteweg MA, Zwanenburg JJM, Hoogduin JM, van den Bosch MAAJ, van Diest PJ, van Hillegersberg R, Eijkemans MJC, Mali WPTM, Luijten PR, Veldhuis WB. Dissected sentinel lymph nodes of breast cancer patients: characterization with high-spatial-resolution 7-T MR imaging. Radiology 2011; 261:127-35. [PMID: 21673230 DOI: 10.1148/radiol.11103535] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
PURPOSE To investigate the association of 7-T magnetic resonance (MR) imaging characteristics with metastatic nodal invasion, determined with histopathologic assessment in dissected sentinel lymph nodes of breast cancer patients. MATERIALS AND METHODS Institutional review board approval and informed consent were obtained. From November 2008 to July 2010, 114 dissected lymph nodes from 33 women (mean age, 57 years; range, 31-80 years) with breast cancer were included. For morphological analysis, three-dimensional (3D) T1-weighted fat-suppressed fast field- (gradient-) echo (isotropic resolution, 180 μm) MR was performed; 3D nodal dimensions, maximum cortical thickness, and presence of fatty hilum were noted. For quantitative parametric analysis, two-dimensional T1-weighted and 3D T2-, T2*-, and diffusion-weighted images were acquired. Statistical analysis included generalized estimating equations (GEEs), forward and backward stepwise regression analyses, and calculation of positive predictive value (PPV) and negative predictive value (NPV). RESULTS Of 114 nodes, 26 (23%) were malignant. Morphological criteria showed weak discriminatory power: A fatty center was absent in 35% of malignant nodes and 30% of benign nodes (P = .9). Nodal volume and length-width ratio were not significantly different (P = .11 and .75, respectively). Cortical thickness (threshold level, 3 mm; P = .02) showed 91% NPV for malignancy and 95% NPV for presence of macrometastases. Quantitative parametric analyses showed comparable mean T1, T2, and T2* relaxation time constants and apparent diffusion coefficient for metastatic and benign nodes: 991 msec, 30 msec, and 18 msec and 0.17 mm²/sec versus 1035 msec (P = .14), 31 msec (P = .001; not significant after GEE), and 15 msec (P = .002) and 0.20 mm²/sec (P = .38), respectively. Mean T2* alone offered an additive discriminatory effect for identification of metastatic nodes. Consistent with the notion of pannodal changes accompanying tumor infiltration, mean T2* differed significantly even if only micrometastases were present. The interindividual differences were small, precluding easy clinical implementation. CONCLUSION Morphological criteria showed poor discriminatory power, even with very-high-spatial-resolution imaging. T2* quantification allowed identification of metastatic nodal invasion.
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Affiliation(s)
- Mies A Korteweg
- Department of Radiology, University Medical Center Utrecht, HP.E01.102, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
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Chen JW, Huang TY, Peng HH, Chen WS, Tseng WYI. Proton resonance frequency shift-weighted imaging for monitoring MR-guided high-intensity focused ultrasound transmissions. J Magn Reson Imaging 2011; 33:1474-81. [PMID: 21591018 DOI: 10.1002/jmri.22582] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
PURPOSE To combine temperature-related information of phase images and magnitude images acquired from an MR spoiled gradient echo sequence using a postprocessing method referred to as PRF-shift-weighted imaging (PRFSWI). MATERIALS AND METHODS Phase images are capable of detecting shifts in proton resonance frequency (PRF) caused by local changes in temperature. Magnitude images provide anatomical information for treatment planning and positioning as well as temperature-related contrast. We used PRFSWI to produce a phase-mask and performed multiplication on the magnitude image to increase temperature-related contrast. RESULTS Through MRI-guided focused ultrasound (MRIgFUS) experiments (both ex vivo and in vivo), we determined that PRFSWI is capable of enhancing the contrast of a heated area even in the initial stages of transmitting high-intensity focused ultrasound energy. CONCLUSION The PRFSWI images are sensitive to changes in temperature and display the heated spot directly in the magnitude images. Although the images do not provide quantitative data related to temperature, this method could be used as a complement to the phase temperature mapping method in the real-time monitoring of MRIgFUS experiments.
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Affiliation(s)
- Jyun-Wen Chen
- Department of Electrical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan
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22
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Korteweg MA, Zwanenburg JJM, van Diest PJ, van den Bosch MAAJ, Luijten PR, van Hillegersberg R, Mali WPTM, Veldhuis WB. Characterization of ex vivo healthy human axillary lymph nodes with high resolution 7 Tesla MRI. Eur Radiol 2010; 21:310-7. [PMID: 20694817 PMCID: PMC3034875 DOI: 10.1007/s00330-010-1915-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 06/18/2010] [Accepted: 07/21/2010] [Indexed: 12/17/2022]
Abstract
Objective To characterize ex vivo healthy human axillary lymph nodes on 7 Tesla MRI and to correlate the findings with pathological analysis as a first step towards non-invasive staging of breast cancer patients in the future. Methods Four axillary lymph node dissection (ALND) specimens from 2 autopsy patients, who had no cancer, were examined on a clinical 7 Tesla MRI system. For morphological analysis a 3D T1-weighted fat-suppressed fast-field-echo [isotropic resolution 180 μm] was acquired. For quantitative analyses 2D T1-, 3D T2-, T2*- and diffusion-weighted images were acquired. The ALNDs were mapped and stained for precise correlation of MRI to pathology. Nodes were sliced in 3 μm sections, Haematoxylin & Eosin stained, and examined by an experienced pathologist. Results MRI detected all 45 nodes and 6 additional nodes that were not detected at pathological analysis. B-cell follicles, efferent- and afferent lymph vessels and blood vessels were identified. Mean T1, T2, T2*, ADC values (± standard deviation) were 944 ± 113 ms, 32 ± 2 ms, 16 ± 2 ms, 0.39 ± 0.09·10−3 mm2/s, respectively. Conclusions 7 Tesla MRI of ex vivo human axillary lymph nodes correlated well with pathology. MRI detected all nodes present in the specimens and allowed visualization of fine structural detail. Pathology-correlated quantitative MRI data are presented.
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Affiliation(s)
- M A Korteweg
- Department of Radiology, University Medical Centre Utrecht, Utrecht, The Netherlands.
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OHWADA HIROSHI, ISHIHARA YASUTOSHI. A Fundamental Numerical Analysis for Noninvasive Thermometry Integrated in a Heating Applicator Based on the Reentrant Cavity. ACTA ACUST UNITED AC 2010. [DOI: 10.3191/thermalmed.26.51] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Mack MG, Vogl TJ, Eichler K, Müller P, Straub R, Roggan A, Felix R. Laser-induced thermoablation of tumours of the head and neck under MR tomographic control. MINIM INVASIV THER 2009. [DOI: 10.3109/13645709809152906] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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D'Arceuil HE, Westmoreland S, de Crespigny AJ. An approach to high resolution diffusion tensor imaging in fixed primate brain. Neuroimage 2007; 35:553-65. [PMID: 17292630 DOI: 10.1016/j.neuroimage.2006.12.028] [Citation(s) in RCA: 160] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2006] [Revised: 12/07/2006] [Accepted: 12/19/2006] [Indexed: 11/20/2022] Open
Abstract
High resolution ex vivo diffusion tensor imaging (DTI) studies of neural tissues can improve our understanding of brain structure. In these studies we can modify the tissue relaxation properties of the fixed tissues to better suite the scanner hardware. We investigated the use of Gd-DTPA contrast agent to provide the optimum signal-to-noise (SNR) ratio in 3D DTI scans of formalin fixed nonhuman primate brains at 4.7 T. Relaxivity measurements in gray and white matter allowed us to optimize the Gd concentration for soaking the brains, resulting in a 2 fold improvement in SNR for the 3D scans. FA changed little with Gd concentrations up to 10 mM although ADC was reduced at 5 and 10 mM. Comparison of in vivo, fresh ex vivo and fixed brains showed no significant FA changes but reductions in ADC of about 50% in fresh ex vivo, and 64% and 80% in fixed gray and white matter respectively. Studies of the temperature dependence of diffusion in these tissues suggested that a 30 degrees increase in sample temperature may yield an improvement of up to 55% in SNR-efficiency for a given diffusion weighting. Our Gd soaking regimen appeared to have no detrimental effect on standard histology of the fixed brain sections. Our methods yield both high SNR and spatial resolution DTI data in fixed primate brains, allowing us to perform high resolution tractography which will facilitate the process of 'validation' of DTI fiber tracts against traditional measures of brain fiber architecture.
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Affiliation(s)
- Helen E D'Arceuil
- Neuroradiology Section, Department of Radiology, Massachusetts General Hospital, Charlestown, MA, USA
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Samson RS, Thornton JS, McLean MA, Williams SCR, Tofts PS. 1H-MRS internal thermometry in test-objects (phantoms) to within 0.1 K for quality assurance in long-term quantitative MR studies. NMR IN BIOMEDICINE 2006; 19:560-5. [PMID: 16612806 DOI: 10.1002/nbm.1033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Many magnetic resonance test-object properties are temperature-dependent, with typical temperature coefficients of approximately 2-3% K(-1). Therefore, to achieve consistent quality assurance measurements to within 1%, test object temperatures should ideally be known to within 0.3 K. Proton magnetic resonance spectroscopy has previously been used to estimate accurately absolute tissue temperature in vivo, based on the linear temperature dependence of the chemical shift difference between water and temperature-stable reference metabolites such as N-acetylaspartate. In this study, this method of 'internal thermometry' in quality assurance test-objects was investigated, and in particular the value of sodium 3-(trimethylsilyl)propane-1-sulfonate (DSS) as a chemical shift reference was demonstrated. The relationship between the DSS-water chemical shift difference (sigma, expressed in ppm) and temperature tau (in K) was shown to be tau = 764.55 (+/-5.05) - 97.72 (+/-1.05) sigma (286 <or= tau <or= 309 K). Internal thermometry in MRI test-objects is feasible and straightforward, using readily available (1)H-MRS pulse sequences and standard spectroscopy evaluation packages, with a minimum detectable temperature difference of 100 (+/-20) mK.
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Affiliation(s)
- R S Samson
- Department of Neuroinflammation, NMR Research Unit, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK.
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Gellermann J, Wlodarczyk W, Hildebrandt B, Ganter H, Nicolau A, Rau B, Tilly W, Fähling H, Nadobny J, Felix R, Wust P. Noninvasive Magnetic Resonance Thermography of Recurrent Rectal Carcinoma in a 1.5 Tesla Hybrid System. Cancer Res 2005; 65:5872-80. [PMID: 15994965 DOI: 10.1158/0008-5472.can-04-3952] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
To implement noninvasive thermometry, we installed a hybrid system consisting of a radiofrequency multiantenna applicator (SIGMA-Eye) for deep hyperthermia (BSD-2000/3D) integrated into the gantry of a 1.5 Tesla magnetic resonance (MR) tomograph Symphony. This system can record MR data during radiofrequency heating and is suitable for application and evaluation of methods for MR thermography. In 15 patients with preirradiated pelvic rectal recurrences, we acquired phase data sets (25 slices) every 10 to 15 minutes over the treatment time (60-90 minutes) using gradient echo sequences (echo time = 20 ms), transformed the phase differences to MR temperatures, and fused the color-coded MR-temperature distributions with anatomic T1-weighted MR data sets. We could generate one complete series of MR data sets per patient with satisfactory quality for further analysis. In fat, muscle, water bolus, prostate, bladder, and tumor, we delineated regions of interest (ROI), used the fat ROI for drift correction by transforming these regions to a phase shift zero, and evaluated the MR-temperature frequency distributions. Mean MR temperatures (T(MR)), maximum T(MR), full width half maximum (FWHM), and other descriptors of tumors and normal tissues were noninvasively derived and their dependencies outlined. In 8 of 15 patients, direct temperature measurements in reference points were available. We correlated the tumor MR temperatures with direct measurements, clinical response, and tumor features (volume and location), and found reasonable trends and correlations. Therefore, the mean T(MR) of the tumor might be useful as a variable to evaluate the quality and effectivity of heat treatments, and consequently as optimization variable. Feasibility of noninvasive MR thermography for regional hyperthermia has been shown and should be further investigated.
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Mack MG, Eichler K, Straub R, Lehnert T, Vogl TJ. MR-guided Laser-induced Thermotherapy of Head and Neck Tumors. ACTA ACUST UNITED AC 2004. [DOI: 10.1078/1615-1615-00129] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Peller M, Kurze V, Loeffler R, Pahernik S, Dellian M, Goetz AE, Issels R, Reiser M. Hyperthermia induces T1 relaxation and blood flow changes in tumors. A MRI thermometry study in vivo. Magn Reson Imaging 2003; 21:545-51. [PMID: 12878265 DOI: 10.1016/s0730-725x(03)00070-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Regional hyperthermia in combination with chemotherapy and/or radiotherapy has proven to be an effective treatment concept for locally advanced deep-seated tumors. Simultaneous MR-imaging could be a promising approach for therapy optimization. Purpose of this study was the in vivo investigation of temperature induced longitudinal relaxation time (T(1)) and blood flow changes in a tumor model. Using a 1.5 Tesla MR system, the T(1) sensitivity on temperature and the onset of tissue changes at temperatures >44 degrees C were investigated in muscle samples. Also, fourteen Syrian Golden Hamsters with amelanotic melanoma A-MEL-3 were examined during heating of the tumors. Temperature induced blood flow and T(1) changes were determined continuously during hyperthermia. Changes of T(1) correlated linearly with temperature over a wide range (27-44 degrees C) in the tissue sample. Tissue changes became notable above 44 degrees C. In the tumor model, relative changes of T(1) (unlike blood flow) showed linear correlation with temperature over the entire range of hyperthermia relevant temperatures (32-44 degrees C). For a low thermal dose, T(1) allows the assessment of temperature changes in tumors in vivo. At higher thermal doses, in addition to temperature changes, T(1) also shows tissue changes. Both temperature and tissue changes supply important information for hyperthermia.
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Affiliation(s)
- Michael Peller
- Department of Clinical Radiology, Ludwig-Maximilians-University, Munich, Germany.
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Prudhomme M, Mattéi-Gazagnes M, Fabbro-Peray P, Puche P, Chabalier JP, Delacrétaz G, François-Michel LFM, Godlewski G. MRI thermodosimetry in laser-induced interstitial thermotherapy. Lasers Surg Med 2003; 32:54-60. [PMID: 12516072 DOI: 10.1002/lsm.10130] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND AND OBJECTIVES The aim of this study was to establish a correlation between a thermal measurement and a magnetic resonance imaging (MRI) signal during laser-induced interstitial thermotherapy (LITT) in liver. STUDY DESIGN/MATERIALS AND METHODS Pig liver was irradiated for 15 minutes with a diode laser at two different powers, 0.5 W (450 J) and 1.5 W (1,350 J). Tissue temperature was monitored every 20 seconds using thermocouples. Thermosensitive MRI sequences (T(1)-weighted Turbo-Flash) were acquired with the same irradiation parameters. Correlation between MRI signals (SI) and temperature measures was defined at two different distances from the fiber (5 and 10 mm). RESULTS At 0.5 W, temperatures rose progressively up to a maximum increase of 9.5 degrees C at 5 mm and 4 degrees C at 10 mm after 15 minutes. The corresponding MRI signal decreased progressively to -27.6 SI at 5 mm and -18.5 SI at 10 mm. At 1.5 W, temperatures rose dramatically at 5 mm, reaching a plateau. The temperature elevation measured at the end of the irradiation was of 30 degrees C whereas at 10 mm it was only 14.5 degrees C. The MRI signal varied accordingly, remaining inversely proportional to temperature (-76 SI at 5 mm and -35.5 SI at 10 mm). CONCLUSIONS An inversely proportional relationship was observed between MRI signal in sequential Turbo-Flash and temperature. MRI should allow to analyze heat diffusion in the liver, and thus to monitor real-time LITT treatments.
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Affiliation(s)
- Michel Prudhomme
- Département de Chirurgie Digestive et de Cancérologie Digestive, rue du Pr R. Debré F30900 Nîmes, France.
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32
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Abstract
Radiofrequency thermal ablation is receiving increasing attention as an alternative to standard surgical therapies for the treatment of liver neoplasms. Benefits over surgical resection include the anticipated reduction in morbidity and mortality, low cost, suitability for real time image guidance, the ability to perform ablative procedures on outpatients, and the potential application in a wider spectrum of patients, including nonsurgical candidates. This review examines reported clinical results of this new therapeutic technique, potential complications, current limitations, thermal ablation mechanisms, as well as technical features and diagnostic modalities used in the procedure.
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Affiliation(s)
- Giuseppe D'Ippolito
- Minimally Invasive Therapies Laboratory, Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
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33
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Peller M, Reinl HM, Weigel A, Meininger M, Issels RD, Reiser M. T1 relaxation time at 0.2 Tesla for monitoring regional hyperthermia: feasibility study in muscle and adipose tissue. Magn Reson Med 2002; 47:1194-201. [PMID: 12111966 DOI: 10.1002/mrm.10155] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The purpose of this study was to characterize T(1), particularly in the hyperthermia temperature range (ca. 37-44 degrees C), in order to control regional hyperthermia with MR monitoring using 0.2 Tesla, and to improve T(1) mapping. A single-slice and a new multislice "T One by Multiple Read-Out Pulses" (TOMROP) pulse sequence were used for fast T(1) mapping in a clinical MRI hyperthermia hybrid system. Temporal stability, temperature sensitivity, and reversibility of T(1) were investigated in a polyamidacryl gel phantom and in samples of muscle and adipose tissues from turkey and pig, and verified in patients. In the gel phantom a high linear correlation between T(1) and temperature (R(2) = 0.97) was observed. In muscle and adipose tissue, T(1) and temperature had a linear relationship below a breakpoint of 43 degrees C. Above this breakpoint muscle tissue showed irreversible tissue changes; these effects were not visible in adipose tissue. The ex vivo results were confirmed in vivo under clinical conditions. T(1) mapping allows the characterization of hyperthermia-related tissue response in healthy tissue. T(1), in combination with fast mapping, is suitable for controlling regional hyperthermia at 0.2 T within the hybrid system.
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Affiliation(s)
- Michael Peller
- Department of Clinical Radiology, Ludwig-Maximilians-University, Munich, Grosshadern, Germany.
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34
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Zuo CS, Mahmood A, Sherry AD. TmDOTA-: a sensitive probe for MR thermometry in vivo. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2001; 151:101-106. [PMID: 11444943 DOI: 10.1006/jmre.2001.2356] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The lanthanide complex, thulium 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (TmDOTA-), has been investigated as an agent for MR thermometry in vivo. The chemical shifts of the TmDOTA- protons were highly sensitive to temperature at a clinically relevant field strength, yet insensitive to pH and the presence of Ca2+. Given the excellent stability of lanthanide-DOTA complexes and high thermal sensitivity, TmDOTA- is expected to be a good candidate for MR thermometry in vivo.
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Affiliation(s)
- C S Zuo
- Department of Radiology, Beth Israel Deaconess Medical Center, One Deaconess Road, Boston, Massachusetts 02215, USA.
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35
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Peters RD, Chan E, Trachtenberg J, Jothy S, Kapusta L, Kucharczyk W, Henkelman RM. Magnetic resonance thermometry for predicting thermal damage: an application of interstitial laser coagulation in an in vivo canine prostate model. Magn Reson Med 2000; 44:873-83. [PMID: 11108624 DOI: 10.1002/1522-2594(200012)44:6<873::aid-mrm8>3.0.co;2-x] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Magnetic resonance image-guidance for interstitial thermal therapy has proven to be a valuable tool in its traditional role in device localization and, more recently, in monitoring heat deposition within tissue. However, a quantitative understanding of how temperature-time exposure relates to thermal damage is crucial if the predictive value of real-time MR thermal-monitoring is to be fully realized. Results are presented on interstitial laser coagulation of two canine prostate models which are shown to provide an opportunity to evaluate three models of thermal damage based on a threshold maximum temperature, an Arrhenius damage integral, and a temperature-time product. These models were compared to the resultant lesion margin as derived from post-treatment T(1)- and T(2)-weighted MR images, as well as from direct histological evaluation of the excised canine prostate. Histological evaluation shows that the thermal-injury boundary can be predicted from a threshold-maximum temperature of approximately 51 degrees C or an equivalent Arrhenius t(43) period of 200 minutes, but it is not reliably predicted using the temperature-time product. The methods described in this study are expected to have implications for the treatment of benign prostatic hyperplasia and prostate cancer with interstitial laser coagulation, which will be the focus of future human studies.
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Affiliation(s)
- R D Peters
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.
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36
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Abstract
Continuous thermometry during a hyperthermic procedure may help to correct for local differences in heat conduction and energy absorption, and thus allow optimization of the thermal therapy. Noninvasive, three-dimensional mapping of temperature changes is feasible with magnetic resonance (MR) and may be based on the relaxation time T(1), the diffusion coefficient (D), or proton resonance frequency (PRF) of tissue water. The use of temperature-sensitive contrast agents and proton spectroscopic imaging can provide absolute temperature measurements. The principles and performance of these methods are reviewed in this paper. The excellent linearity and near-independence with respect to tissue type, together with good temperature sensitivity, make PRF-based temperature MRI the preferred choice for many applications at mid to high field strength (>/= 1 T). The PRF methods employ radiofrequency spoiled gradient-echo imaging methods. A standard deviation of less than 1 degrees C, for a temporal resolution below 1 second and a spatial resolution of about 2 mm, is feasible for a single slice for immobile tissues. Corrections should be made for temperature-induced susceptibility effects in the PRF method. If spin-echo methods are preferred, for example when field homogeneity is poor due to small ferromagnetic parts in the needle, the D- and T(1)-based methods may give better results. The sensitivity of the D method is higher that that of the T(1) methods provided that motion artifacts are avoided and the trace of D is evaluated. Fat suppression is necessary for most tissues when T(1), D, or PRF methods are employed. The latter three methods require excellent registration to correct for displacements between scans.
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Affiliation(s)
- B Quesson
- Résonance Magnétique des Systèmes Biologiques, UMR 5536 CNRS/Victor Segalen, University Bordeaux 2, F-33076 Bordeaux, France
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37
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Steiner P, Schoenenberger AW, Erhart P, Penner E, von Schulthess GK, Debatin JF. Imaging temperature changes in an interventional 0.5 T magnet: in-vitro results. Lasers Surg Med 2000; 21:464-73. [PMID: 9365957 DOI: 10.1002/(sici)1096-9101(1997)21:5<464::aid-lsm8>3.0.co;2-o] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND AND OBJECTIVE To evaluate the ability of monitoring laser induced temperature changes in an open, interventional 0.5 T magnet, adopting fast T1-weighted sequences. MATERIALS AND METHODS A fast gradient echo- (FGRE) and a fast spoiled gradient echo-sequence (FSPGR), both enabling an image update every 2.5 s, were investigated for their ability to visualize laser tissue effects at 5 Watt. Laser induced temperature was fluorooptically measured and correlated with signal intensity (SI) changes depicted by magnetic resonance imaging (MRI). MRI-lesions were compared with macroscopic findings. RESULTS SI changes on FGRE images appeared as early as 15 s following the onset of laser application and were significantly more pronounced than those seen on FSPGR images (p < .0001). A correlation of r = 0.94 (FGRE) and r = 0.92 (FSPGR) between temperature and SI loss was established. Owing to a steeper slope, the FGRE sequence was considered more sensitive to temperature changes. The areas of macroscopic tissue change correlated with those of SI loss, but lesion size was generally underestimated by MRI. CONCLUSION Laser monitoring is possible with rapid image updates in a midfield (0.5 T) interventional MRI environment using fast gradient echo sequence designs.
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Affiliation(s)
- P Steiner
- Department of Radiology, University Hospital Zurich, Switzerland
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38
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Abstract
The aim of the study was to test the hypothesis that fast spin echo T(1)-weighted images can be used to quantify the temperature in fat during thermal therapy in vivo. An MR compatible positioning device was used to manipulate focused ultrasound transducers in an MRI scanner. This system was used to sonicate fat tissue around the kidneys of 12 rabbits at various power levels for 10 to 20 sec. The scan parameters of T(1)-weighted fast spin echo (FSE) sequence were varied to optimize signal intensity characteristics while maintaining short scan times. An invasive optical probe was used to calibrate the temperature related signal intensity changes. For the T(1)-weighted FSE sequence, the signal intensity decreased with the temperature elevation at the rate of 0.97+/-0.02%/ degrees C. The single focused transducer produced a contrast-to-noise ratio more than 10 at power levels below the tissue damage threshold. The signal intensity was linearly dependent on the power, despite the measured temperatures being well above the coagulation threshold. This study demonstrates that T(1)-weighted FSE MRI sequences can be used to quantify the temperature elevation in fat in vivo during short focused ultrasound exposures. This can be very important for breast tumor surgery, fat ablation, and for treating deep seated tumors through superficial fat layers. Magn Reson Med 43:901-904, 2000.
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Affiliation(s)
- K Hynynen
- Department of Radiology, Division of MRI, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
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39
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Shapiro EM, Borthakur A, Bansal N, Leigh JS, Reddy R. Temperature-dependent chemical shift and relaxation times of (23)Na in Na(4)HTm[DOTP]. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2000; 143:213-216. [PMID: 10698662 DOI: 10.1006/jmre.1999.2000] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We describe the characterization of a (23)Na temperature-dependent chemical shift and relaxation rates in the complex, Na(4)HTm[DOTP]. This is the first characterization of a (23)Na temperature-dependent chemical shift in a nonmetallic sample. The (23)Na temperature-dependent chemical shift coefficient is approximately -0. 5 PPM/ degrees C for both an aqueous solution and a 6% agarose gel of this compound. This is 50 times the magnitude of the temperature-dependent chemical shift coefficient of water protons. The relaxation times, T(1), T(2f), and T(2s) increased by 0.1, 0.01, and 0.05 ms/ degrees C, respectively. Applications of these unique properties for designing an MRI technique for monitoring heat deposition in tissue and tissue phantoms are discussed.
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Affiliation(s)
- E M Shapiro
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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40
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Nott KP, Hall LD, Bows JR, Hale M, Patrick ML. MRI phase mapping of temperature distributions induced in food by microwave heating. Magn Reson Imaging 2000; 18:69-79. [PMID: 10642104 DOI: 10.1016/s0730-725x(99)00103-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A range of temperature-sensitive MRI parameters of water (T2, T1, diffusion coefficient, and chemical shift) were evaluated to map in three dimensions the non-uniform temperature distributions induced by microwave heating in both model and real food systems. Phase mapping was found to be the most robust method, and evaluations of possible experimental errors were based on semi-quantitative studies of homogeneous and heterogeneous systems. The MRI protocol provides complementary phase and magnitude data, which are related to the sample temperature and structural heterogeneity, respectively. Used together, they relate the temperature changes to the differential thermal properties of the various components within a heterogeneous sample. The potential applications of this technique to microwave and other forms of heating is discussed.
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Affiliation(s)
- K P Nott
- Herchel Smith Laboratory for Medicinal Chemistry, University of Cambridge School of Clinical Medicine, UK
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41
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42
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Nott KP, Bows JR, Patrick ML. Three-dimensional MRI mapping of microwave induced heating patterns. Int J Food Sci Technol 1999. [DOI: 10.1046/j.1365-2621.1999.00286.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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43
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Peters RD, Hinks RS, Henkelman RM. Heat-source orientation and geometry dependence in proton-resonance frequency shift magnetic resonance thermometry. Magn Reson Med 1999; 41:909-18. [PMID: 10332873 DOI: 10.1002/(sici)1522-2594(199905)41:5<909::aid-mrm9>3.0.co;2-n] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The proton-resonance frequency (PRF) shift method of thermometry has become a promising tool for magnetic resonance image-guided thermal therapies. Although the PRF thermal coefficient has recently been shown to be independent of tissue type when measured ex vivo, significant discrepancy remains on its value for tissues measured in vivo under a variety of experimental conditions. The authors identify a potential source of variation in the PRF thermal coefficient that arises from temperature-induced changes in the volume magnetic susceptibility of tissue and is dependent on the orientation and geometry of the heat-delivery device and its associated heat pattern. This study demonstrates that spatial variations in the apparent PRF thermal coefficient could lead to errors of up to +/-30% in the magnetic resonance estimated temperature change if this effect is ignored.
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Affiliation(s)
- R D Peters
- Department of Medical Biophysics, University of Toronto, Sunnybrook Health Science Centre, Canada.
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44
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Günther RW, Bücker A, Adam G. Interventional magnetic resonance: realistic prospect or wishful thinking? Cardiovasc Intervent Radiol 1999; 22:187-95. [PMID: 10382047 DOI: 10.1007/s002709900364] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- R W Günther
- Department of Diagnostic Radiology, RWTH Aachen, Technical University of Aachen, Germany
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45
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Mueller-Lisse UG, Thoma M, Faber S, Heuck AF, Muschter R, Schneede P, Weninger E, Hofstetter AG, Reiser MF. Coagulative interstitial laser-induced thermotherapy of benign prostatic hyperplasia: online imaging with a T2-weighted fast spin-echo MR sequence--experience in six patients. Radiology 1999; 210:373-9. [PMID: 10207417 DOI: 10.1148/radiology.210.2.r99fe49373] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To determine if hypointense lesions clearly outline on T2-weighted fast spin-echo (SE) magnetic resonance (MR) images obtained during coagulative interstitial laser-induced thermotherapy (LITT) of a prostate with benign hyperplasia. MATERIALS AND METHODS In six patients with benign prostatic hyperplasia (BPH), 12 LITT treatments were followed online with repetitive axial T2-weighted fast SE imaging (repetition time, 3,700 msec; echo time, 138 msec; acquisition time, 19 seconds). Development, time course, correlation with interstitial tissue temperature, and diameters of hypointense lesions around the laser diffusor tip were investigated. Lesion diameters on T2-weighted images acquired during LITT were compared with diameters of final lesions on T2-weighted images and unperfused lesions on enhanced T1-weighted SE images obtained at the end of therapy. RESULTS Hypointense lesions developed within 20-40 seconds of LITT. Average correlation coefficients between interstitial temperature development and signal intensity development were 0.92 during LITT and 0.90 after LITT. Regression slopes were significantly steeper during LITT (0.67% signal intensity change per degree Celsius) than after LITT (0.47% per degree Celsius; P = .038). Lesions remained visible after LITT for all procedures. Average maximum diameters of lesions were 1-3 mm larger during LITT than after LITT (P = .0006-.019). CONCLUSION Repetitive T2-weighted fast SE MR imaging during interstitial coagulative LITT of BPH demonstrates the development of permanent hypointense prostate lesions. However, posttherapeutic lesion diameters tend to be overestimated during LITT.
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Affiliation(s)
- U G Mueller-Lisse
- Department of Diagnostic Radiology, Klinikum Grosshadern, University of Munich Ludwig Maximilian, Germany
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46
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Peters RD, Hinks RS, Henkelman RM. Ex vivo tissue-type independence in proton-resonance frequency shift MR thermometry. Magn Reson Med 1998; 40:454-9. [PMID: 9727949 DOI: 10.1002/mrm.1910400316] [Citation(s) in RCA: 264] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The temperature sensitivity of the proton-resonance frequency (PRF) has proven valuable for the monitoring of MR image-guided thermal coagulation therapy. However, there is significant inconsistency in reported values of the PRF-thermal coefficient, as measured from experiments encompassing a range of in vivo and ex vivo tissue types and experimental conditions. A method of calibrating the temperature dependence of the PRF is described and results are presented that indicate a tissue-type independence. To this end, other possible mechanisms for variations in the PRF-thermal coefficient are suggested, including physiological perturbations and volume magnetic susceptibility effects from geometry and orientation.
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Affiliation(s)
- R D Peters
- Department of Medical Biophysics, University of Toronto, Sunnybrook Health Science Center, Ontario, Canada
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47
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Zuo CS, Metz KR, Sun Y, Sherry AD. NMR temperature measurements using a paramagnetic lanthanide complex. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 1998; 133:53-60. [PMID: 9654468 DOI: 10.1006/jmre.1998.1429] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
NMR thermometry has previously suffered from poor thermal resolution owing to the relatively weak dependence of chemical shift on temperature in diamagnetic molecules. In contrast, the shifts of nuclear spins near a paramagnetic center exhibit strong temperature dependencies. The chemical shifts of the thulium 1,4,7, 10-tetraazacyclododecane-1,4,7,10-tetrakis(methylene phosphonate) complex (TmDOTP5-) have been studied as a function of temperature, pH, and Ca2+ concentration over ranges which may be encountered in vivo. The results demonstrate that the 1H and 31P shifts in TmDOTP5- are highly sensitive to temperature and may be used for NMR thermometry with excellent accuracy and resolution. A new technique is also described which permits simultaneous measurements of temperature and pH changes from the shifts of multiple TmDOTP5- spectral lines.
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Affiliation(s)
- C S Zuo
- Department of Radiology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, 02215, USA
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48
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Abstract
In the investigation of ischemic stroke, conventional structural magnetic resonance (MR) techniques (e.g., T1-weighted imaging, T2-weighted imaging, and proton density-weighted imaging) are valuable for the assessment of infarct extent and location beyond the first 12 to 24 hours after onset, and can be combined with MR angiography to noninvasively assess the intracranial and extracranial vasculature. However, during the critical first 6 to 12 hours, the probable period of greatest therapeutic opportunity, these methods do not adequately assess the extent and severity of ischemia. Recent developments in functional MR imaging are showing great promise for the detection of developing focal cerebral ischemic lesions within the first hours. These include (1) diffusion-weighted imaging, which provides physiologic information about the self-diffusion of water, thereby detecting one of the first elements in the pathophysiologic cascade leading to ischemic injury; and (2) perfusion imaging. The detection of acute intraparenchymal hemorrhagic stroke by susceptibility weighted MR has also been reported. In combination with MR angiography, these methods may allow the detection of the site, extent, mechanism, and tissue viability of acute stroke lesions in one imaging study. Imaging of cerebral metabolites with MR spectroscopy along with diffusion-weighted imaging and perfusion imaging may also provide new insights into ischemic stroke pathophysiology. In light of these advances in structural and functional MR, their potential uses in the study of the cerebral ischemic pathophysiology and in clinical practice are described, along with their advantages and limitations.
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Affiliation(s)
- A E Baird
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
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49
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Bertsch F, Mattner J, Stehling MK, Müller-Lisse U, Peller M, Loeffler R, Weber J, Messmer K, Wilmanns W, Issels R, Reiser M. Non-invasive temperature mapping using MRI: comparison of two methods based on chemical shift and T1-relaxation. Magn Reson Imaging 1998; 16:393-404. [PMID: 9665550 DOI: 10.1016/s0730-725x(97)00311-1] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
PURPOSE To implement and evaluate the accuracy of non-invasive temperature mapping using MRI methods based on the chemical shift (CS) and T1 relaxation in media of various heterogeneity during focal (laser) and external thermal energy deposition. MATERIALS AND METHODS All measurements were performed on a 1.5 T superconducting clinical scanner using the temperature dependence of the water proton chemical shift and the T1 relaxation time. Homogeneous gel and heterogeneous muscle phantoms were heated focally with a fiberoptic laser probe and externally of varying degree ex vivo by water circulating in a temperature range of 20-50 degrees C. Magnetic resonance imaging data were compared to simultaneously recorded fiberoptic temperature readings. RESULTS Both methods provided accurate results in homogeneous media (turkey) with better accuracy for the chemical shift method (CS:+/-1.5 degrees C, T1:+/-2.0 degrees C). In gel, the accuracy with the CS method was +/-0.6 degrees C. The accuracy decreased in heterogeneous media containing fat (T1:+/-3.5 degrees C, CS: +5 degrees C). In focal heating of turkey muscle, the accuracy was within 1.5 degrees C with the T1 method. CONCLUSION Temperature monitoring with the chemical shift provides better results in homogeneous media containing no fat. In fat tissue, the temperature calculation proved to be difficult.
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Affiliation(s)
- F Bertsch
- Institut für Radiologische Diagnostik, Ludwig Maximilians Universität, München, Germany.
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50
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Interventional MR with a Hybrid High-Field System. INTERVENTIONAL MAGNETIC RESONANCE IMAGING 1998. [DOI: 10.1007/978-3-642-60272-6_3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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