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Avoiding Pitfalls in Thermal Dose Effect Relationship Studies: A Review and Guide Forward. Cancers (Basel) 2022; 14:cancers14194795. [PMID: 36230717 PMCID: PMC9562191 DOI: 10.3390/cancers14194795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 09/23/2022] [Accepted: 09/26/2022] [Indexed: 11/16/2022] Open
Abstract
The challenge to explain the diffuse and unconclusive message reported by hyperthermia studies investigating the thermal dose parameter is still to be unravelled. In the present review, we investigated a wide range of technical and clinical parameters characterising hyperthermia treatment to better understand and improve the probability of detecting a thermal dose effect relationship in clinical studies. We performed a systematic literature review to obtain hyperthermia clinical studies investigating the associations of temperature and thermal dose parameters with treatment outcome or acute toxicity. Different hyperthermia characteristics were retrieved, and their influence on temperature and thermal dose parameters was assessed. In the literature, we found forty-eight articles investigating thermal dose effect relationships. These comprised a total of 4107 patients with different tumour pathologies. The association between thermal dose and treatment outcome was the investigated endpoint in 90% of the articles, while the correlation between thermal dose and toxicity was investigated in 50% of the articles. Significant associations between temperature-related parameters and treatment outcome were reported in 63% of the studies, while those between temperature-related parameters and toxicity were reported in 15% of the studies. One clear difficulty for advancement is that studies often omitted fundamental information regarding the clinical treatment, and among the different characteristics investigated, thermometry details were seldom and divergently reported. To overcome this, we propose a clear definition of the terms and characteristics that should be reported in clinical hyperthermia treatments. A consistent report of data will allow their use to further continue the quest for thermal dose effect relationships.
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Badawi MI, Hafez KS. The significance of nanoparticles in brain cancer diagnosis and treatment: modeling and simulation. Biomed Phys Eng Express 2022; 8. [PMID: 35405668 DOI: 10.1088/2057-1976/ac6629] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 04/11/2022] [Indexed: 11/12/2022]
Abstract
A numerical analysis of specific absorption rate (SAR) and temperature distributions in a realistic human head model is presented in this study. The key challenge is to rise cancer temperature to an optimal temperature without heating nearby healthy tissues. The model's uniqueness is that it captures the effect of nanoparticles on both brain cancer diagnosis and treatment. A realistic human head model with a cancerous brain segmented from 2D magnetic resonance imaging (MRI) gained from an actual patient using 3D Slicer, modeled, and simulated using CST-Microwave Studio, and illuminated by Archimedes spiral antenna. At frequencies of 2450 MHz and 915 MHz, the model simulated the absence and presence of various nanoparticles. The obtained results suggest that when using nanoparticles, it is possible to achieve sufficient energy deposition and temperature rise to therapeutic values (greater than 42 °C) in brain cancers using the proposed noninvasive hyperthermia system at 915 MHz frequency, especially for gold nanoparticles, without harming surrounding healthy tissue. Our research might pave the way for a clinical applicator prototype that can heat brain cancer.
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Affiliation(s)
- Mohamed I Badawi
- Biomedical Equipment Technology Department, Faculty of Applied Health Sciences Technology, Pharos University, Alexandria, Egypt
| | - Karim S Hafez
- Biomedical Equipment Technology Department, Faculty of Applied Health Sciences Technology, Pharos University, Alexandria, Egypt
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Kok HP, Cressman ENK, Ceelen W, Brace CL, Ivkov R, Grüll H, Ter Haar G, Wust P, Crezee J. Heating technology for malignant tumors: a review. Int J Hyperthermia 2021; 37:711-741. [PMID: 32579419 DOI: 10.1080/02656736.2020.1779357] [Citation(s) in RCA: 132] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The therapeutic application of heat is very effective in cancer treatment. Both hyperthermia, i.e., heating to 39-45 °C to induce sensitization to radiotherapy and chemotherapy, and thermal ablation, where temperatures beyond 50 °C destroy tumor cells directly are frequently applied in the clinic. Achievement of an effective treatment requires high quality heating equipment, precise thermal dosimetry, and adequate quality assurance. Several types of devices, antennas and heating or power delivery systems have been proposed and developed in recent decades. These vary considerably in technique, heating depth, ability to focus, and in the size of the heating focus. Clinically used heating techniques involve electromagnetic and ultrasonic heating, hyperthermic perfusion and conductive heating. Depending on clinical objectives and available technology, thermal therapies can be subdivided into three broad categories: local, locoregional, or whole body heating. Clinically used local heating techniques include interstitial hyperthermia and ablation, high intensity focused ultrasound (HIFU), scanned focused ultrasound (SFUS), electroporation, nanoparticle heating, intraluminal heating and superficial heating. Locoregional heating techniques include phased array systems, capacitive systems and isolated perfusion. Whole body techniques focus on prevention of heat loss supplemented with energy deposition in the body, e.g., by infrared radiation. This review presents an overview of clinical hyperthermia and ablation devices used for local, locoregional, and whole body therapy. Proven and experimental clinical applications of thermal ablation and hyperthermia are listed. Methods for temperature measurement and the role of treatment planning to control treatments are discussed briefly, as well as future perspectives for heating technology for the treatment of tumors.
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Affiliation(s)
- H Petra Kok
- Department of Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Erik N K Cressman
- Department of Interventional Radiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Wim Ceelen
- Department of GI Surgery, Ghent University Hospital, Ghent, Belgium
| | - Christopher L Brace
- Department of Radiology and Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Robert Ivkov
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Mechanical Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD, USA.,Department of Materials Science and Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Holger Grüll
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine, University Hospital of Cologne, University of Cologne, Cologne, Germany
| | - Gail Ter Haar
- Department of Physics, The Institute of Cancer Research, London, UK
| | - Peter Wust
- Department of Radiation Oncology, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Johannes Crezee
- Department of Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
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Zhu L, Lam D, Pacia CP, Gach HM, Partanen A, Talcott MR, Greco SC, Zoberi I, Hallahan DE, Chen H, Altman MB. Characterization of magnetic resonance-guided high-intensity focused ultrasound (MRgHIFU)-induced large-volume hyperthermia in deep and superficial targets in a porcine model. Int J Hyperthermia 2020; 37:1159-1173. [DOI: 10.1080/02656736.2020.1825836] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- Lifei Zhu
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Dao Lam
- Department of Radiation Oncology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Christopher Pham Pacia
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, USA
| | - H. Michael Gach
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Radiation Oncology, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Radiology, Washington University in St. Louis, St. Louis, Missouri, USA
- Siteman Comprehensive Cancer Center, St. Louis, St. Louis, Missouri, USA
| | - Ari Partanen
- Clinical Science, Profound Medical Inc, Mississauga, Ontario, Canada
| | - Michael R. Talcott
- Division of Comparative Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Suellen C. Greco
- Division of Comparative Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Imran Zoberi
- Department of Radiation Oncology, Washington University in St. Louis, St. Louis, Missouri, USA
- Siteman Comprehensive Cancer Center, St. Louis, St. Louis, Missouri, USA
| | - Dennis E. Hallahan
- Department of Radiation Oncology, Washington University in St. Louis, St. Louis, Missouri, USA
- Siteman Comprehensive Cancer Center, St. Louis, St. Louis, Missouri, USA
| | - Hong Chen
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Radiation Oncology, Washington University in St. Louis, St. Louis, Missouri, USA
- Siteman Comprehensive Cancer Center, St. Louis, St. Louis, Missouri, USA
| | - Michael B. Altman
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Radiation Oncology, Washington University in St. Louis, St. Louis, Missouri, USA
- Siteman Comprehensive Cancer Center, St. Louis, St. Louis, Missouri, USA
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Datta NR, Kok HP, Crezee H, Gaipl US, Bodis S. Integrating Loco-Regional Hyperthermia Into the Current Oncology Practice: SWOT and TOWS Analyses. Front Oncol 2020; 10:819. [PMID: 32596144 PMCID: PMC7303270 DOI: 10.3389/fonc.2020.00819] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 04/27/2020] [Indexed: 12/14/2022] Open
Abstract
Moderate hyperthermia at temperatures between 40 and 44°C is a multifaceted therapeutic modality. It is a potent radiosensitizer, interacts favorably with a host of chemotherapeutic agents, and, in combination with radiotherapy, enforces immunomodulation akin to “in situ tumor vaccination.” By sensitizing hypoxic tumor cells and inhibiting repair of radiotherapy-induced DNA damage, the properties of hyperthermia delivered together with photons might provide a tumor-selective therapeutic advantage analogous to high linear energy transfer (LET) neutrons, but with less normal tissue toxicity. Furthermore, the high LET attributes of hyperthermia thermoradiobiologically are likely to enhance low LET protons; thus, proton thermoradiotherapy would mimic 12C ion therapy. Hyperthermia with radiotherapy and/or chemotherapy substantially improves therapeutic outcomes without enhancing normal tissue morbidities, yielding level I evidence reported in several randomized clinical trials, systematic reviews, and meta-analyses for various tumor sites. Technological advancements in hyperthermia delivery, advancements in hyperthermia treatment planning, online invasive and non-invasive MR-guided thermometry, and adherence to quality assurance guidelines have ensured safe and effective delivery of hyperthermia to the target region. Novel biological modeling permits integration of hyperthermia and radiotherapy treatment plans. Further, hyperthermia along with immune checkpoint inhibitors and DNA damage repair inhibitors could further augment the therapeutic efficacy resulting in synthetic lethality. Additionally, hyperthermia induced by magnetic nanoparticles coupled to selective payloads, namely, tumor-specific radiotheranostics (for both tumor imaging and radionuclide therapy), chemotherapeutic drugs, immunotherapeutic agents, and gene silencing, could provide a comprehensive tumor-specific theranostic modality akin to “magic (nano)bullets.” To get a realistic overview of the strength (S), weakness (W), opportunities (O), and threats (T) of hyperthermia, a SWOT analysis has been undertaken. Additionally, a TOWS analysis categorizes future strategies to facilitate further integration of hyperthermia with the current treatment modalities. These could gainfully accomplish a safe, versatile, and cost-effective enhancement of the existing therapeutic armamentarium to improve outcomes in clinical oncology.
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Affiliation(s)
- Niloy R Datta
- Centre for Radiation Oncology KSA-KSB, Kantonsspital Aarau, Aarau, Switzerland
| | - H Petra Kok
- Department of Radiation Oncology, Cancer Center Amsterdam, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Hans Crezee
- Department of Radiation Oncology, Cancer Center Amsterdam, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Udo S Gaipl
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Stephan Bodis
- Centre for Radiation Oncology KSA-KSB, Kantonsspital Aarau, Aarau, Switzerland
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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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Kok HP, Groen J, Bakker A, Crezee J. Modelling Curved Contact Flexible Microstrip Applicators for Patient-Specific Superficial Hyperthermia Treatment Planning. Cancers (Basel) 2020; 12:cancers12030656. [PMID: 32168959 PMCID: PMC7139424 DOI: 10.3390/cancers12030656] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 03/05/2020] [Accepted: 03/10/2020] [Indexed: 12/18/2022] Open
Abstract
This paper describes a method to reconstruct bendable superficial hyperthermia applicators for routine clinical patient-specific treatment planning. The reconstruction uses a CT scan with a flexible silicone dummy applicator positioned on the patient. The curvature was approximated by two second-degree polynomial functions. A realistic treatment series was mimicked using a standard Alderson radiation therapy phantom and a treatment planning model was reconstructed from a CT scan. The variation among treatment curvatures was compared to the modelled curvature. The mathematical approximation of the applicator curvature was validated for this phantom experiment, as well as for clinical treatments. The average maximum variation among the successive mimicked sessions was 3.67 ± 0.69 mm (range 2.98-4.60mm). The maximum deviation between the treatment curvature and the modelled curvature was 4.35 mm. Comparing the treatment and approximated curvature yielded a maximum deviation between 2.98 mm and 4.12 mm. For clinical treatments the maximum deviation of the treatment and approximated curvature varied between 0.48 mm and 1.98 mm. These results allow adequate reconstruction of bendable hyperthermia applicators for treatment planning, which can further improve treatment quality, for example by optimizing the water bolus temperature for patient-specific tumor depths. Predictive parameters for hyperthermia treatment outcome can easily be evaluated and compared for various input parameters.
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Zhao Y, Luo Y, Guo T, Tang Z, Zhou Z. A Novel Amphiphilic AIE Molecule and Its Application in Thermosensitive Liposome. ChemistrySelect 2019. [DOI: 10.1002/slct.201900976] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Yun‐Hui Zhao
- School of Chemistry and Chemical EngineeringHunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine PolymersHunan University of Science and Technology, Xiangtan, Hunan 411201 China
- Key Laboratory of Synthetic Chemistry of Natural SubstancesShanghai Institute of Organic ChemistryChinese Academy of Sciences Shanghai 200032 China
| | - Yueyang Luo
- School of Chemistry and Chemical EngineeringHunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine PolymersHunan University of Science and Technology, Xiangtan, Hunan 411201 China
| | - Tao Guo
- College of ChemistryChemical and Environmental EngineeringHenan University of Technology Zhengzhou Henan 450001 China
| | - Zilong Tang
- School of Chemistry and Chemical EngineeringHunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine PolymersHunan University of Science and Technology, Xiangtan, Hunan 411201 China
| | - Zhihua Zhou
- School of Chemistry and Chemical EngineeringHunan Provincial Key Laboratory of Controllable Preparation and Functional Application of Fine PolymersHunan University of Science and Technology, Xiangtan, Hunan 411201 China
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Quality assurance guidelines for superficial hyperthermia clinical trials : II. Technical requirements for heating devices. Strahlenther Onkol 2017; 193:351-366. [PMID: 28251250 PMCID: PMC5405104 DOI: 10.1007/s00066-017-1106-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 01/27/2017] [Indexed: 11/04/2022]
Abstract
Quality assurance (QA) guidelines are essential to provide uniform execution of clinical trials with uniform quality hyperthermia treatments. This document outlines the requirements for appropriate QA of all current superficial heating equipment including electromagnetic (radiative and capacitive), ultrasound, and infrared heating techniques. Detailed instructions are provided how to characterize and document the performance of these hyperthermia applicators in order to apply reproducible hyperthermia treatments of uniform high quality. Earlier documents used specific absorption rate (SAR) to define and characterize applicator performance. In these QA guidelines, temperature rise is the leading parameter for characterization of applicator performance. The intention of this approach is that characterization can be achieved with affordable equipment and easy-to-implement procedures. These characteristics are essential to establish for each individual applicator the specific maximum size and depth of tumors that can be heated adequately. The guidelines in this document are supplemented with a second set of guidelines focusing on the clinical application. Both sets of guidelines were developed by the European Society for Hyperthermic Oncology (ESHO) Technical Committee with participation of senior Society of Thermal Medicine (STM) members and members of the Atzelsberg Circle.
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Trefná HD, Crezee H, Schmidt M, Marder D, Lamprecht U, Ehmann M, Hartmann J, Nadobny J, Gellermann J, van Holthe N, Ghadjar P, Lomax N, Abdel-Rahman S, Bert C, Bakker A, Hurwitz MD, Diederich CJ, Stauffer PR, van Rhoon GC. Quality assurance guidelines for superficial hyperthermia clinical trials: I. Clinical requirements. Int J Hyperthermia 2017; 33:471-482. [PMID: 28049386 DOI: 10.1080/02656736.2016.1277791] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Quality assurance guidelines are essential to provide uniform execution of clinical trials and treatment in the application of hyperthermia. This document provides definitions for a good hyperthermia treatment and identifies the clinical conditions where a certain hyperthermia system can or cannot adequately heat the tumour volume. It also provides brief description of the characteristics and performance of the current electromagnetic (radiative and capacitive), ultrasound and infra-red heating techniques. This information helps to select the appropriate heating technique for the specific tumour location and size, and appropriate settings of the water bolus and thermometry. Finally, requirements of staff training and documentation are provided. The guidelines in this document focus on the clinical application and are complemented with a second, more technical quality assurance document providing instructions and procedure to determine essential parameters that describe heating properties of the applicator for superficial hyperthermia. Both sets of guidelines were developed by the ESHO Technical Committee with participation of senior STM members and members of the Atzelsberg Circle.
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Affiliation(s)
| | - Hans Crezee
- b Radiotherapy , AMC , Amsterdam , The Netherlands
| | - Manfred Schmidt
- c Radiotherapy Clinics, Universitatsklinikum Erlangen , Erlangen , Germany
| | | | - Ulf Lamprecht
- e Radiation Oncology , University Hospital Tuebingen , Tuebingen , Germany
| | - Michael Ehmann
- f Radiation Oncology , University Medical Centre Mannheim , Mannheim , Germany
| | - Josefin Hartmann
- c Radiotherapy Clinics, Universitatsklinikum Erlangen , Erlangen , Germany
| | - Jacek Nadobny
- g Klinik für Radioonkologie und Strahlentherapie , Campus Virchow Klinikum, Charite Universitatsmedizin Berlin , Berlin , Germany
| | - Johanna Gellermann
- e Radiation Oncology , University Hospital Tuebingen , Tuebingen , Germany.,h Praxis/Zentrum für Strahlentherapie und Radioonkologie , Berlin , Germany
| | - Netteke van Holthe
- i Radiation Oncology , Erasmus MC Daniel den Hoed Cancer Center , Rotterdam , The Netherlands
| | - Pirus Ghadjar
- g Klinik für Radioonkologie und Strahlentherapie , Campus Virchow Klinikum, Charite Universitatsmedizin Berlin , Berlin , Germany
| | | | - Sultan Abdel-Rahman
- j Department of Internal Medicine III , Ludwig Maximilians University of Munich , Munich , Germany
| | - Christoph Bert
- c Radiotherapy Clinics, Universitatsklinikum Erlangen , Erlangen , Germany.,k Department of Biophysics , GSI - Helmholtz Centre for Heavy Ion Research , Darmstadt , Germany
| | - Akke Bakker
- b Radiotherapy , AMC , Amsterdam , The Netherlands
| | - Mark D Hurwitz
- l Department of Radiation Oncology , Thomas Jefferson University , Philadelphia , PA , USA
| | - Chris J Diederich
- m Department of Radiation Oncology , UCSF , San Francisco , CA , USA
| | - Paul R Stauffer
- l Department of Radiation Oncology , Thomas Jefferson University , Philadelphia , PA , USA
| | - Gerard C van Rhoon
- i Radiation Oncology , Erasmus MC Daniel den Hoed Cancer Center , Rotterdam , The Netherlands
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Müller J, Hartmann J, Bert C. Infrared camera based thermometry for quality assurance of superficial hyperthermia applicators. Phys Med Biol 2016; 61:2646-64. [DOI: 10.1088/0031-9155/61/7/2646] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Vrba D, Rodrigues DB, Vrba (Jr.) J, Stauffer PR. METAMATERIAL ANTENNA ARRAYS FOR IMPROVED UNIFORMITY OF MICROWAVE HYPERTHERMIA TREATMENTS. ACTA ACUST UNITED AC 2016. [DOI: 10.2528/pier16012702] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Curto S, Prakash P. Design of a compact antenna with flared groundplane for a wearable breast hyperthermia system. Int J Hyperthermia 2015; 31:726-36. [PMID: 26368277 DOI: 10.3109/02656736.2015.1063170] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE Currently available microwave hyperthermia systems for breast cancer treatment do not conform to the intact breast and provide limited control of heating patterns, thereby hindering an effective treatment. A compact patch antenna with a flared groundplane that may be integrated within a wearable hyperthermia system for the treatment of the intact breast disease is proposed. MATERIALS AND METHODS A 3D simulation-based approach was employed to optimise the antenna design with the objective of maximising the hyperthermia treatment volume (41 °C iso-therm) while maintaining good impedance matching. The optimised antenna design was fabricated and experimentally evaluated with ex vivo tissue measurements. RESULTS The optimised compact antenna yielded a -10 dB bandwidth of 90 MHz centred at 915 MHz, and was capable of creating hyperthermia treatment volumes up to 14.4 cm(3) (31 mm × 28 mm × 32 mm) with an input power of 15 W. Experimentally measured reflection coefficient and transient temperature profiles were in good agreement with simulated profiles. Variations of + 50% in blood perfusion yielded variations in the treatment volume up to 11.5%. When compared to an antenna with a similar patch element employing a conventional rectangular groundplane, the antenna with flared groundplane afforded 22.3% reduction in required power levels to reach the same temperature, and yielded 2.4 times larger treatment volumes. CONCLUSION The proposed patch antenna with a flared groundplane may be integrated within a wearable applicator for hyperthermia treatment of intact breast targets and has the potential to improve efficiency, increase patient comfort, and ultimately clinical outcomes.
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Affiliation(s)
- Sergio Curto
- a Department of Electrical and Computer Engineering , Kansas State University , Manhattan , Kansas , USA
| | - Punit Prakash
- a Department of Electrical and Computer Engineering , Kansas State University , Manhattan , Kansas , USA
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Liang X, Gao J, Jiang L, Luo J, Jing L, Li X, Jin Y, Dai Z. Nanohybrid liposomal cerasomes with good physiological stability and rapid temperature responsiveness for high intensity focused ultrasound triggered local chemotherapy of cancer. ACS NANO 2015; 9:1280-93. [PMID: 25599568 DOI: 10.1021/nn507482w] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The high intensity focused ultrasound (HIFU) and thermosensitive cerasomes (HTSCs) were successfully assembled by employing cerasome-forming lipid (CFL) in combination with the component lipids of conventional low temperature sensitive liposomes (LTSLs) including 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DSPE-PEG-2000) and 1-stearoyl-2-hydroxy-sn-glycero-3-phosphocholine (MSPC). The HTSCs showed spherical shape with a mean diameter around 200 nm, exhibiting good biocompatibility. Both hydrophilic and lipophilic drugs can be efficiently encapsulated into HTSCs. In addition, the release rate of HTSCs could be conveniently adjusted by varying the molar ratios of CFL to DPPC. The drug loaded HTSCs showed much longer blood circulation time (half-life >8.50 ± 1.49 h) than conventional LTSLs (0.92 ± 0.17 h). An in vitro study demonstrated that the drug loaded HTSCs are highly stable at 37 °C and show a burst release at 42 °C, providing a capability to act synergistically against tumors. We found that the HTSCs with a proportion of 43.25% of CFL could release more than 90% hydrophilic drugs in 1 min at an elevated temperature of 42 °C generated by HIFU exposure. After intravenous injection of doxorubicin (DOX) loaded HTSCs at 5 mg DOX/kg, followed by double HIFU sonication, the tumor growth of the adenocarcinoma (MDA-MB-231) bearing mice could be significantly inhibited. Therefore, the drug loaded HTSCs combined with HIFU hold great potential for efficient local chemotherapy of cancer due to the ability to deliver high concentration of chemotherapy drugs directly to the tumor, achieve maximum therapeutic efficacy and minimal side effects, and avoid the damage to the healthy tissues caused by systemic administration of drugs.
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Affiliation(s)
- Xiaolong Liang
- Department of Biomedical Engineering, College of Engineering, Peking University , Beijing 100871, China
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Partanen A, Tillander M, Yarmolenko PS, Wood BJ, Dreher MR, Kohler MO. Reduction of peak acoustic pressure and shaping of heated region by use of multifoci sonications in MR-guided high-intensity focused ultrasound mediated mild hyperthermia. Med Phys 2013; 40:013301. [PMID: 23298120 DOI: 10.1118/1.4769116] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
PURPOSE Ablative hyperthermia (>55 °C) has been used as a definitive treatment for accessible solid tumors not amenable to surgery, whereas mild hyperthermia (40-45 °C) has been shown effective as an adjuvant for both radiotherapy and chemotherapy. An optimal mild hyperthermia treatment is spatially accurate, with precise and homogeneous heating limited to the target region while also limiting the likelihood of unwanted thermal or mechanical bioeffects (tissue damage, vascular shutoff). Magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) can noninvasively heat solid tumors under image-guidance. In a mild hyperthermia setting, a sonication approach utilizing multiple concurrent foci may provide the benefit of reducing acoustic pressure in the focal region (leading to reduced or no mechanical effects), while providing better control over the heating. The objective of this study was to design, implement, and characterize a multifoci sonication approach in combination with a mild hyperthermia heating algorithm, and compare it to the more conventional method of electronically sweeping a single focus. METHODS Simulations (acoustic and thermal) and measurements (acoustic, with needle hydrophone) were performed. In addition, heating performance of multifoci and single focus sonications was compared using a clinical MR-HIFU platform in a phantom (target = 4-16 mm), in normal rabbit thigh muscle (target = 8 mm), and in a Vx2 tumor (target = 8 mm). A binary control algorithm was used for real-time mild hyperthermia feedback control (target range = 40.5-41 °C). Data were analyzed for peak acoustic pressure and intensity, heating energy efficiency, temperature accuracy (mean), homogeneity of heating (standard deviation [SD], T10 and T90), diameter and length of the heated region, and thermal dose (CEM(43)). RESULTS Compared to the single focus approach, multifoci sonications showed significantly lower (67% reduction) peak acoustic pressures in simulations and hydrophone measurements. In a rabbit Vx2 tumor, both single focus and multifoci heating approaches were accurate (mean = 40.82±0.12 °C [single] and 40.70±0.09 °C [multi]) and precise (standard deviation = 0.65±0.05 °C [single] and 0.64±0.04 °C [multi]), producing homogeneous heating (T(10-90) = 1.62 °C [single] and 1.41 °C [multi]). Heated regions were significantly shorter in the beam path direction (35% reduction, p < 0.05, Tukey) for multifoci sonications, i.e., resulting in an aspect ratio closer to one. Energy efficiency was lower for the multifoci approach. Similar results were achieved in phantom and rabbit muscle heating experiments. CONCLUSIONS A multifoci sonication approach was combined with a mild hyperthermia heating algorithm, and implemented on a clinical MR-HIFU platform. This approach resulted in accurate and precise heating within the targeted region with significantly lower acoustic pressures and spatially more confined heating in the beam path direction compared to the single focus sonication method.The reduction in acoustic pressure and improvement in spatial control suggest that multifoci heating is a useful tool in mild hyperthermia applications for clinical oncology.
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Affiliation(s)
- Ari Partanen
- National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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de Smet M, Langereis S, van den Bosch S, Bitter K, Hijnen NM, Heijman E, Grüll H. SPECT/CT imaging of temperature-sensitive liposomes for MR-image guided drug delivery with high intensity focused ultrasound. J Control Release 2013; 169:82-90. [PMID: 23598044 DOI: 10.1016/j.jconrel.2013.04.005] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 04/01/2013] [Accepted: 04/04/2013] [Indexed: 01/30/2023]
Abstract
The goal of this study was to investigate the blood kinetics and biodistribution of temperature-sensitive liposomes (TSLs) for MR image-guided drug delivery. The co-encapsulated doxorubicin and [Gd(HPDO3A)(H₂O)] as well as the ¹¹¹In-labeled liposomal carrier were quantified in blood and organs of tumor bearing rats. After TSL injection, mild hyperthermia (T=42 °C) was induced in the tumor using high intensity focused ultrasound under MR image-guidance (MR-HIFU). The biodistribution of the radiolabeled TSLs was investigated using SPECT/CT imaging, where the highest uptake of ¹¹¹In-labeled TSLs was observed in the spleen and liver. The MR-HIFU-treated tumors showed 4.4 times higher liposome uptake after 48 h in comparison with controls, while the doxorubicin concentration was increased by a factor of 7.9. These effects of HIFU-treatment are promising for applications in liposomal drug delivery to tumors.
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Affiliation(s)
- Mariska de Smet
- Department of Biomedical Engineering, Biomedical NMR, Eindhoven University of Technology, Eindhoven, The Netherlands
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Partanen A, Yarmolenko PS, Viitala A, Appanaboyina S, Haemmerich D, Ranjan A, Jacobs G, Woods D, Enholm J, Wood BJ, Dreher MR. Mild hyperthermia with magnetic resonance-guided high-intensity focused ultrasound for applications in drug delivery. Int J Hyperthermia 2012; 28:320-36. [PMID: 22621734 DOI: 10.3109/02656736.2012.680173] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
PURPOSE Mild hyperthermia (40-45 °C) is a proven adjuvant for radiotherapy and chemotherapy. Magnetic resonance guided high intensity focused ultrasound (MR-HIFU) can non-invasively heat solid tumours under image guidance. Low temperature-sensitive liposomes (LTSLs) release their drug cargo in response to heat (>40 °C) and may improve drug delivery to solid tumours when combined with mild hyperthermia. The objective of this study was to develop and implement a clinically relevant MR-HIFU mild hyperthermia heating algorithm for combination with LTSLs. MATERIALS AND METHODS Sonications were performed with a clinical MR-HIFU platform in a phantom and rabbits bearing VX2 tumours (target = 4-16 mm). A binary control algorithm was used for real-time mild hyperthermia feedback control (target = 40-41 °C). Drug delivery with LTSLs was measured with HPLC. Data were compared to simulation results and analysed for spatial targeting accuracy (offset), temperature accuracy (mean), homogeneity of heating (standard deviation (SD), T10 and T90), and thermal dose (CEM43). RESULTS Sonications in a phantom resulted in better temperature control than in vivo. Sonications in VX2 tumours resulted in mean temperatures between 40.4 °C and 41.3 °C with a SD of 1.0-1.5 °C (T10 = 41.7-43.7 °C, T90 = 39.0-39.6 °C), in agreement with simulations. 3D spatial offset was 0.1-3.2 mm in vitro and 0.6-4.8 mm in vivo. Combination of MR-HIFU hyperthermia and LTSLs demonstrated heterogeneous delivery to a partially heated VX2 tumour, as expected. CONCLUSIONS An MR-HIFU mild hyperthermia heating algorithm was developed, resulting in accurate and homogeneous heating within the targeted region in vitro and in vivo, which is suitable for applications in drug delivery.
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Affiliation(s)
- Ari Partanen
- Center for Interventional Oncology, Clinical Center, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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Smrkovski OA, Koo Y, Kazemi R, Lembcke LM, Fathy A, Liu Q, Phillips JC. Performance characteristics of a conformal ultra-wideband multilayer applicator (CUMLA) for hyperthermia in veterinary patients: a pilot evaluation of its use in the adjuvant treatment of non-resectable tumours. Vet Comp Oncol 2011; 11:14-29. [DOI: 10.1111/j.1476-5829.2011.00297.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Johnson JE, O'Shaughnessy KF, Kim S. Microwave thermolysis of sweat glands. Lasers Surg Med 2011; 44:20-5. [DOI: 10.1002/lsm.21142] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/13/2011] [Indexed: 11/12/2022]
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Stauffer PR, Maccarini P, Arunachalam K, Craciunescu O, Diederich C, Juang T, Rossetto F, Schlorff J, Milligan A, Hsu J, Sneed P, Vujaskovic Z. Conformal microwave array (CMA) applicators for hyperthermia of diffuse chest wall recurrence. Int J Hyperthermia 2010; 26:686-98. [PMID: 20849262 DOI: 10.3109/02656736.2010.501511] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE This article summarises the evolution of microwave array applicators for heating large area chest wall disease as an adjuvant to external beam radiation, systemic chemotherapy, and potentially simultaneous brachytherapy. METHODS Current devices used for thermotherapy of chest wall recurrence are reviewed. The largest conformal array applicator to date is evaluated in four studies: (1) ability to conform to the torso is demonstrated with a CT scan of a torso phantom and MR scan of the conformal water bolus component on a mastectomy patient; (2) specific absorption rate (SAR) and temperature distributions are calculated with electromagnetic and thermal simulation software for a mastectomy patient; (3) SAR patterns are measured with a scanning SAR probe in liquid muscle phantom for a buried coplanar waveguide CMA; and (4) heating patterns and patient tolerance of CMA applicators are characterised in a clinical pilot study with 13 patients. RESULTS CT and MR scans demonstrate excellent conformity of CMA applicators to contoured anatomy. Simulations demonstrate effective control of heating over contoured anatomy. Measurements confirm effective coverage of large treatment areas with no gaps. In 42 hyperthermia treatments, CMA applicators provided well-tolerated effective heating of up to 500 cm(2) regions, achieving target temperatures of T(min) = 41.4 ± 0.7°C, T(90) = 42.1 ± 0.6°C, T(ave) = 42.8 ± 0.6°C, and T(max) = 44.3 ± 0.8°C as measured in an average of 90 points per treatment. CONCLUSION The CMA applicator is an effective thermal therapy device for heating large-area superficial disease such as diffuse chest wall recurrence. It is able to cover over three times the treatment area of conventional hyperthermia devices while conforming to typical body contours.
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Affiliation(s)
- Paul R Stauffer
- Radiation Oncology Department, Duke University, Durham, NC 27710, USA.
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Canters RAM, Wust P, Bakker JF, Van Rhoon GC. A literature survey on indicators for characterisation and optimisation of SAR distributions in deep hyperthermia, a plea for standardisation. Int J Hyperthermia 2010; 25:593-608. [PMID: 19848621 DOI: 10.3109/02656730903110539] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE To evaluate the predictive value of SAR indicators by assessing the correlation of a SAR indicator with the corresponding predicted temperature. Ultimately, this should lead to a number of verified SAR indicators for characterization and optimization of a predicted SAR distribution. METHODS A literature survey is followed by an evaluation of the SAR indicators on their functionality, using a set of heuristic classification criteria. To obtain an objective assessment of the predictive value for SAR characterisation, all SAR indicators are evaluated by correlating the value of the SAR indicator to the predicted target temperature when heated with the BSD2000 Sigma 60 applicator. Two methods were followed. First, the specificity of the SAR indicator to target temperature was assessed for each of the 36 patient-specific models, using 30 randomly chosen phase and amplitude settings. Secondly, each SAR indicator was used as a goal function to assess its suitability for optimisation purposes. RESULTS Only a selected number of SAR indicators correlate well with tumour/target-temperature. Hence, for target-related properties, an adequate set of SAR indicators is found in the literature. For hotspots, modifications are desirable. For optimisation purposes, improved objective functions have been defined. CONCLUSIONS From the correlation of the SAR indicators with tumour temperature, a preferred set of SAR indicators is derived: For target heating, 'average SAR ratio', 'Hotspot-target SAR ratio', and 'homogeneity coefficient' provide suitable objective criteria, while for hotspot reduction, 'Hotspot-target SAR ratio' is considered the most useful indicator. For optimisation procedures, 'Hotspot-target SAR ratio' is currently the most suitable objective function.
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Affiliation(s)
- R A M Canters
- Erasmus Medical Center, Radiation Oncology Department, Hyperthermia Unit, Rotterdam, The Netherlands.
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Arunachalam K, Maccarini PF, Stauffer PR. A thermal monitoring sheet with low influence from adjacent waterbolus for tissue surface thermometry during clinical hyperthermia. IEEE Trans Biomed Eng 2008; 55:2397-406. [PMID: 18838365 DOI: 10.1109/tbme.2008.925693] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
This paper presents a complete thermal analysis of a novel conformal surface thermometer design with directional sensitivity for real-time temperature monitoring during hyperthermia treatments of large superficial cancer. The thermal monitoring sheet (TMS) discussed in this paper consists of a 2-D array of fiberoptic sensors embedded between two layers of flexible, low-loss, and thermally conductive printed circuit board (PCB) film. Heat transfer across all interfaces from the tissue surface through multiple layers of insulating dielectrics surrounding the small buried temperature sensor and into an adjacent temperature-regulated water coupling bolus was studied using 3-D thermal simulation software. Theoretical analyses were carried out to identify the most effective differential TMS probe configuration possible with commercially available flexible PCB materials and to compare their thermal responses with omnidirectional probes commonly used in clinical hyperthermia. A TMS sensor design that employs 0.0508-mm Kapton MTB and 0.2032-mm Kapton HN flexible polyimide films is proposed for tissue surface thermometry with low influence from the adjacent waterbolus. Comparison of the thermal simulations with clinical probes indicates the new differential TMS probe design to outperform in terms of both transient response and steady-state accuracy in selectively reading the tissue surface temperature, while decreasing the overall thermal barrier of the probe between the coupling waterbolus and tissue surface.
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Affiliation(s)
- Kavitha Arunachalam
- Department of Radiation Oncology, Hyperthermia Physics Division, Duke University Medical Center, Durham, NC 27713, USA.
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Arunachalam K, Maccarini P, Juang T, Gaeta C, Stauffer PR. Performance evaluation of a conformal thermal monitoring sheet sensor array for measurement of surface temperature distributions during superficial hyperthermia treatments. Int J Hyperthermia 2008; 24:313-25. [PMID: 18465416 PMCID: PMC2730925 DOI: 10.1080/02656730701881133] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
PURPOSE This paper presents a novel conformal thermal monitoring sheet (TMS) sensor array with differential thermal sensitivity for measuring temperature distributions over large surface areas. Performance of the sensor array is evaluated in terms of thermal accuracy, mechanical stability and conformity to contoured surfaces, probe self-heating under irradiation from microwave and ultrasound hyperthermia sources, and electromagnetic field perturbation. MATERIALS AND METHODS A prototype with 4 x 4 array of fiber-optic sensors embedded between two flexible and thermally conducting polyimide films was developed as an alternative to the standard 1-2 mm diameter plastic catheter-based probes used in clinical hyperthermia. Computed tomography images and bending tests were performed to evaluate the conformability and mechanical stability respectively. Irradiation and thermal barrier tests were conducted and thermal response of the prototype was compared with round cross-sectional clinical probes. RESULTS Bending and conformity tests demonstrated higher flexibility, dimensional stability and close conformity to human torso. Minimal perturbation of microwave fields and low probe self-heating was observed when irradiated with 915 MHz microwave and 3.4 MHz ultrasound sources. The transient and steady state thermal responses of the TMS array were superior compared to the clinical probes. CONCLUSIONS A conformal TMS sensor array with improved thermal sensitivity and dimensional stability was investigated for real-time skin temperature monitoring. This fixed-geometry, body-conforming array of thermal sensors allows fast and accurate characterization of two-dimensional temperature distributions over large surface areas. The prototype TMS demonstrates significant advantages over clinical probes for characterizing skin temperature distributions during hyperthermia treatments of superficial tissue disease.
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Affiliation(s)
- K Arunachalam
- Radiation Oncology, Duke University Medical Center, Durham, NC 27705, USA.
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de Bruijne M, Samaras T, Chavannes N, van Rhoon GC. Quantitative validation of the 3D SAR profile of hyperthermia applicators using the gamma method. Phys Med Biol 2007; 52:3075-88. [PMID: 17505090 DOI: 10.1088/0031-9155/52/11/010] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
For quality assurance of hyperthermia treatment planning systems, quantitative validation of the electromagnetic model of an applicator is essential. The objective of this study was to validate a finite-difference time-domain (FDTD) model implementation of the Lucite cone applicator (LCA) for superficial hyperthermia. The validation involved (i) the assessment of the match between the predicted and measured 3D specific absorption rate (SAR) distribution, and (ii) the assessment of the ratio between model power and real-world power. The 3D SAR distribution of seven LCAs was scanned in a phantom bath using the DASY4 dosimetric measurement system. The same set-up was modelled in SEMCAD X. The match between the predicted and the measured SAR distribution was quantified with the gamma method, which combines distance-to-agreement and dose difference criteria. Good quantitative agreement was observed: more than 95% of the measurement points met the acceptance criteria 2 mm/2% for all applicators. The ratio between measured and predicted power absorption ranged from 0.75 to 0.92 (mean 0.85). This study shows that quantitative validation of hyperthermia applicator models is feasible and is worth considering as a part of hyperthermia quality assurance procedures.
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Affiliation(s)
- Maarten de Bruijne
- Hyperthermia Unit, Department of Radiation Oncology, Erasmus MC-Daniel den Hoed Cancer Center, Rotterdam, The Netherlands.
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