1
|
Jiao L, Zhang T, Gao P, Zhou C, Mei X, Zhang W, Lu Y, Zhang L, Zhou Z, Yu Z, He M. Exploring and validating heating dynamics in a radio-frequency electromagnetic field-based resonant chamber for mouse hyperthermia research. Electromagn Biol Med 2024; 43:164-175. [PMID: 38859623 DOI: 10.1080/15368378.2024.2361873] [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: 02/02/2024] [Accepted: 05/26/2024] [Indexed: 06/12/2024]
Abstract
Mild whole-body hyperthermia has been shown to have anti-tumor effects through an immune-modulating mechanism. Before it is widely applied in the clinic, tremendous mechanistic research in animals is necessary to adhere to evidence-based principles. The radio frequency electromagnetic field (RF-EMF) based heating facility could be a good choice for hyperthermia treatment, but the heating characteristics of a facility, including structure design, electromagnetic and thermal dosimetry, and the biologic effects of hyperthermia, need to be well elucidated. Here, we reported the heating characteristic study on a resonant chamber (RC) excited by a 1800 MHz solid source. The EMF in the RC was stirred by 24 static reflectors, which resulted in the standard deviation of electric field intensity being below 3 dB in the EM homogeneity evaluation. For the exposure scenario, six free-moving mice were loaded into separate cases and exposed simultaneously in the RC. The EMF energy absorption and distribution in exposed mice were calculated with the 12-plane-waves method of numerical simulation. Different levels of core body temperature increment in exposed mice were achieved through regulation of the source output power. Overexpression of heat shock proteins (HSPs) was detected in the liver, lung and muscle, but not in the brain of the exposed mice. The levels of representative inflammatory cytokines in the serum, TNF-α and IL-10 increased post RC exposure. Based on the heating characteristic study and validation, the applied RC would be a qualified heating system for mild whole-body hyperthermia effect research in mice.
Collapse
Affiliation(s)
- Lijiao Jiao
- Key Laboratory of Medical Protection for Electromagnetic Radiation, Ministry of Education, Department of Occupational Health, Army Medical University, Chongqing, China
- Department of Nursing, General Hospital of Northern Theater Command, Shenyang, Liaoning Province, People's Republic of China
| | - Tao Zhang
- Key Laboratory of Medical Protection for Electromagnetic Radiation, Ministry of Education, Department of Occupational Health, Army Medical University, Chongqing, China
| | - Peng Gao
- Key Laboratory of Medical Protection for Electromagnetic Radiation, Ministry of Education, Department of Occupational Health, Army Medical University, Chongqing, China
| | - Chao Zhou
- Key Laboratory of Medical Protection for Electromagnetic Radiation, Ministry of Education, Department of Occupational Health, Army Medical University, Chongqing, China
- Xizang Autonomous Region, China
| | - Xiang Mei
- Key Laboratory of Medical Protection for Electromagnetic Radiation, Ministry of Education, Department of Occupational Health, Army Medical University, Chongqing, China
| | - Wenjuan Zhang
- Key Laboratory of Medical Protection for Electromagnetic Radiation, Ministry of Education, Department of Occupational Health, Army Medical University, Chongqing, China
| | - Yonghui Lu
- Key Laboratory of Medical Protection for Electromagnetic Radiation, Ministry of Education, Department of Occupational Health, Army Medical University, Chongqing, China
| | - Lei Zhang
- Key Laboratory of Medical Protection for Electromagnetic Radiation, Ministry of Education, Department of Occupational Health, Army Medical University, Chongqing, China
| | - Zhou Zhou
- Center for Neurointelligence, School of Medicine, Chongqing University, Chongqing, China
| | - Zhengping Yu
- Key Laboratory of Medical Protection for Electromagnetic Radiation, Ministry of Education, Department of Occupational Health, Army Medical University, Chongqing, China
| | - Mindi He
- Key Laboratory of Medical Protection for Electromagnetic Radiation, Ministry of Education, Department of Occupational Health, Army Medical University, Chongqing, China
| |
Collapse
|
2
|
Miziev S, Pawlak WA, Howard N. Comparative analysis of energy transfer mechanisms for neural implants. Front Neurosci 2024; 17:1320441. [PMID: 38292898 PMCID: PMC10825050 DOI: 10.3389/fnins.2023.1320441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 12/19/2023] [Indexed: 02/01/2024] Open
Abstract
As neural implant technologies advance rapidly, a nuanced understanding of their powering mechanisms becomes indispensable, especially given the long-term biocompatibility risks like oxidative stress and inflammation, which can be aggravated by recurrent surgeries, including battery replacements. This review delves into a comprehensive analysis, starting with biocompatibility considerations for both energy storage units and transfer methods. The review focuses on four main mechanisms for powering neural implants: Electromagnetic, Acoustic, Optical, and Direct Connection to the Body. Among these, Electromagnetic Methods include techniques such as Near-Field Communication (RF). Acoustic methods using high-frequency ultrasound offer advantages in power transmission efficiency and multi-node interrogation capabilities. Optical methods, although still in early development, show promising energy transmission efficiencies using Near-Infrared (NIR) light while avoiding electromagnetic interference. Direct connections, while efficient, pose substantial safety risks, including infection and micromotion disturbances within neural tissue. The review employs key metrics such as specific absorption rate (SAR) and energy transfer efficiency for a nuanced evaluation of these methods. It also discusses recent innovations like the Sectored-Multi Ring Ultrasonic Transducer (S-MRUT), Stentrode, and Neural Dust. Ultimately, this review aims to help researchers, clinicians, and engineers better understand the challenges of and potentially create new solutions for powering neural implants.
Collapse
|
3
|
Bottauscio O, Rubia-Rodríguez I, Arduino A, Zilberti L, Chiampi M, Ortega D. Heating of metallic biliary stents during magnetic hyperthermia of patients with pancreatic ductal adenocarcinoma: an in silico study. Int J Hyperthermia 2022; 39:1222-1232. [DOI: 10.1080/02656736.2022.2121863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
Affiliation(s)
| | | | | | - Luca Zilberti
- Istituto Nazionale di Ricerca Metrologica (INRIM), Turin, Italy
| | - Mario Chiampi
- Istituto Nazionale di Ricerca Metrologica (INRIM), Turin, Italy
| | - Daniel Ortega
- IMDEA Nanoscience, Madrid, Spain
- Condensed Matter Physics Department, University of Cádiz, Cádiz, Spain
- Institute of Research and Innovation in Biomedical Sciences of Cádiz (INiBICA), University of Cádiz, Cádiz, Spain
| |
Collapse
|
4
|
Sumser K, Drizdal T, Bellizzi GG, Hernandez-Tamames JA, van Rhoon GC, Paulides MM. Experimental Validation of the MRcollar: An MR Compatible Applicator for Deep Heating in the Head and Neck Region. Cancers (Basel) 2021; 13:5617. [PMID: 34830773 PMCID: PMC8615935 DOI: 10.3390/cancers13225617] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 10/29/2021] [Accepted: 11/08/2021] [Indexed: 12/13/2022] Open
Abstract
Clinical effectiveness of hyperthermia treatments, in which tumor tissue is artificially heated to 40-44 °C for 60-90 min, can be hampered by a lack of accurate temperature monitoring. The need for noninvasive temperature monitoring in the head and neck region (H&N) and the potential of MR thermometry prompt us to design an MR compatible hyperthermia applicator: the MRcollar. In this work, we validate the design, numerical model, and MR performance of the MRcollar. The MRcollar antennas have low reflection coefficients (<-15 dB) and the intended low interaction between the individual antenna modules (<-32 dB). A 10 °C increase in 3 min was reached in a muscle-equivalent phantom, such that the specifications from the European Society for Hyperthermic Oncology were easily reached. The MRcollar had a minimal effect on MR image quality and a five-fold improvement in SNR was achieved using the integrated coils of the MRcollar, compared to the body coil. The feasibility of using the MRcollar in an MR environment was shown by a synchronous heating experiment. The match between the predicted SAR and measured SAR using MR thermometry satisfied the gamma criteria [distance-to-agreement = 5 mm, dose-difference = 7%]. All experiments combined show that the MRcollar delivers on the needs for MR-hyperthermia in the H&N and is ready for in vivo investigation.
Collapse
Affiliation(s)
- Kemal Sumser
- Department of Radiotherapy, Erasmus Medical Center Cancer Institute, 3015 GD Rotterdam, The Netherlands; (T.D.); (G.G.B.); (G.C.v.R.); (M.M.P.)
| | - Tomas Drizdal
- Department of Radiotherapy, Erasmus Medical Center Cancer Institute, 3015 GD Rotterdam, The Netherlands; (T.D.); (G.G.B.); (G.C.v.R.); (M.M.P.)
- Department of Biomedical Technology, Czech Technical University in Prague, nam. Sítna 3105, 272 01 Kladno, Czech Republic
| | - Gennaro G. Bellizzi
- Department of Radiotherapy, Erasmus Medical Center Cancer Institute, 3015 GD Rotterdam, The Netherlands; (T.D.); (G.G.B.); (G.C.v.R.); (M.M.P.)
| | - Juan A. Hernandez-Tamames
- Department of Radiology and Nuclear Medicine, Erasmus Medical Center Cancer Institute, 3015 GD Rotterdam, The Netherlands;
| | - Gerard C. van Rhoon
- Department of Radiotherapy, Erasmus Medical Center Cancer Institute, 3015 GD Rotterdam, The Netherlands; (T.D.); (G.G.B.); (G.C.v.R.); (M.M.P.)
| | - Margarethus Marius Paulides
- Department of Radiotherapy, Erasmus Medical Center Cancer Institute, 3015 GD Rotterdam, The Netherlands; (T.D.); (G.G.B.); (G.C.v.R.); (M.M.P.)
- Department of Electrical Engineering, Eindhoven University of Technology, 5612 AZ Eindhoven, The Netherlands
| |
Collapse
|
5
|
Priester MI, Curto S, van Rhoon GC, ten Hagen TLM. External Basic Hyperthermia Devices for Preclinical Studies in Small Animals. Cancers (Basel) 2021; 13:cancers13184628. [PMID: 34572855 PMCID: PMC8470307 DOI: 10.3390/cancers13184628] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 09/09/2021] [Accepted: 09/10/2021] [Indexed: 02/07/2023] Open
Abstract
Simple Summary The application of mild hyperthermia can be beneficial for solid tumor treatment by induction of sublethal effects on a tissue- and cellular level. When designing a hyperthermia experiment, several factors should be taken into consideration. In this review, multiple elementary hyperthermia devices are described in detail to aid standardization of treatment design. Abstract Preclinical studies have shown that application of mild hyperthermia (40–43 °C) is a promising adjuvant to solid tumor treatment. To improve preclinical testing, enhance reproducibility, and allow comparison of the obtained results, it is crucial to have standardization of the available methods. Reproducibility of methods in and between research groups on the same techniques is crucial to have a better prediction of the clinical outcome and to improve new treatment strategies (for instance with heat-sensitive nanoparticles). Here we provide a preclinically oriented review on the use and applicability of basic hyperthermia systems available for solid tumor thermal treatment in small animals. The complexity of these techniques ranges from a simple, low-cost water bath approach, irradiation with light or lasers, to advanced ultrasound and capacitive heating devices.
Collapse
Affiliation(s)
- Marjolein I. Priester
- Laboratory of Experimental Oncology, Department of Pathology, Erasmus University Medical Center, 3015 GD Rotterdam, The Netherlands;
- Department of Radiotherapy, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands; (S.C.); (G.C.v.R.)
| | - Sergio Curto
- Department of Radiotherapy, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands; (S.C.); (G.C.v.R.)
| | - Gerard C. van Rhoon
- Department of Radiotherapy, Erasmus MC Cancer Institute, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands; (S.C.); (G.C.v.R.)
| | - Timo L. M. ten Hagen
- Laboratory of Experimental Oncology, Department of Pathology, Erasmus University Medical Center, 3015 GD Rotterdam, The Netherlands;
- Correspondence:
| |
Collapse
|
6
|
Rubia-Rodríguez I, Zilberti L, Arduino A, Bottauscio O, Chiampi M, Ortega D. In silico assessment of collateral eddy current heating in biocompatible implants subjected to magnetic hyperthermia treatments. Int J Hyperthermia 2021; 38:846-861. [PMID: 34074196 DOI: 10.1080/02656736.2021.1909758] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Purpose: Bearing partially or fully metallic passive implants represents an exclusion criterion for patients undergoing a magnetic hyperthermia procedure, but there are no specific studies backing this restrictive decision. This work assesses how the secondary magnetic field generated at the surface of two common types of prostheses affects the safety and efficiency of magnetic hyperthermia treatments of localized tumors. The paper also proposes the combination of a multi-criteria decision analysis and a graphical representation of calculated data as an initial screening during the preclinical risk assessment for each patient.Materials and methods: Heating of a hip joint and a dental implant during the treatment of prostate, colorectal and head and neck tumors have been assessed considering different external field conditions and exposure times. The Maxwell equations including the secondary field produced by metallic prostheses have been solved numerically in a discretized computable human model. The heat exchange problem has been solved through a modified version of the Pennes' bioheat equation assuming a temperature dependency of blood perfusion and metabolic heat, i.e. thermorregulation. The degree of risk has been assessed using a risk index with parameters coming from custom graphs plotting the specific absorption rate (SAR) vs temperature increase, and coefficients derived from a multi-criteria decision analysis performed following the MACBETH approach.Results: The comparison of two common biomaterials for passive implants - Ti6Al4V and CoCrMo - shows that both specific absorption rate (SAR) and local temperature increase are found to be higher for the hip prosthesis made by Ti6Al4V despite its lower electrical and thermal conductivity. By tracking the time evolution of temperature upon field application, it has been established that there is a 30 s delay between the time point for which the thermal equilibrium is reached at prostheses and tissues. Likewise, damage may appear in those tissues adjacent to the prostheses at initial stages of treatment, since recommended thermal thresholds are soon surpassed for higher field intensities. However, it has also been found that under some operational conditions the typical safety rule of staying below or attain a maximum temperature increase or SAR value is met.Conclusion: The current exclusion criterion for implant-bearing patients in magnetic hyperthermia should be revised, since it may be too restrictive for a range of the typical field conditions used. Systematic in silico treatment planning using the proposed methodology after a well-focused diagnostic procedure can aid the clinical staff to find the appropriate limits for a safe treatment window.
Collapse
Affiliation(s)
| | - Luca Zilberti
- Istituto Nazionale di Ricerca Metrologica (INRIM), Turin, Italy
| | | | | | - Mario Chiampi
- Istituto Nazionale di Ricerca Metrologica (INRIM), Turin, Italy
| | - Daniel Ortega
- IMDEA Nanoscience, Madrid, Spain.,Institute of Research and Innovation in Biomedical Sciences of the Province of Cádiz (INiBICA), University of Cádiz, Cádiz, Spain.,Condensed Matter Physics department, University of Cádiz, Cádiz, Spain
| |
Collapse
|
7
|
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.
Collapse
|
8
|
Gentilal N, Salvador R, Miranda PC. Temperature control in TTFields therapy of GBM: impact on the duty cycle and tissue temperature. Phys Med Biol 2019; 64:225008. [PMID: 31671414 DOI: 10.1088/1361-6560/ab5323] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In TTFields therapy, Optune® is used to deliver the electric field to the tumor via 4 transducer arrays. This device monitors the temperature of the transducers and reduces the current whenever a transducer reaches 41 °C. Our aim is to quantify Optune's duty cycle and to predict the steady-state temperature distribution in the head during GBM treatment. We used a realistic head model and the finite element method to solve Pennes equation and to simulate how Optune operates considering that current reduces to zero when the thermal limit is reached. The thermal impact was evaluated considering the maximum temperature reached by each tissue and using the CEM 43 °C metric. We observed that Optune switches the current on and off intermittently. In our model, one transducer reached the temperature limit quicker than the others and consequently it was the one that controlled current injection. This led to different duty cycles for the anterior-posterior and left-right array pairs. The thermal analysis indicated that the highest temperature in the model, 41.7 °C, was reached on the scalp under a transducer. However, TTFields may lead to significant changes only at the brain level such as BBB permeability increase, cerebral blood flow variation and changes in the concentration of some neurotransmitters. The duty cycle may be increased, e.g. by controlling the current at the transducer level. These predictions should be validated by comparison with experimental data and reconciled with the lack of evidence of thermal impact in clinical trials.
Collapse
Affiliation(s)
- Nichal Gentilal
- Institute of Biophysics and Biomedical Engineering, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016, Lisboa, Portugal. Author to whom correspondence should be addressed
| | | | | |
Collapse
|
9
|
Role of Simulations in the Treatment Planning of Radiofrequency Hyperthermia Therapy in Clinics. JOURNAL OF ONCOLOGY 2019; 2019:9685476. [PMID: 31558904 PMCID: PMC6735211 DOI: 10.1155/2019/9685476] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 07/20/2019] [Accepted: 07/28/2019] [Indexed: 12/26/2022]
Abstract
Hyperthermia therapy is a treatment modality in which tumor temperatures are elevated to higher temperatures to cause damage to cancerous tissues. Numerical simulations are integral in the development of hyperthermia treatment systems and in clinical treatment planning. In this study, simulations in radiofrequency hyperthermia therapy are reviewed in terms of their technical development and clinical aspects for effective clinical use. This review offers an overview of mathematical models and the importance of tissue properties; locoregional mild hyperthermia therapy, including phantom and realistic human anatomy models; phase array systems; tissue damage; thermal dose analysis; and thermoradiotherapy planning. This review details the improvements in numerical approaches in treatment planning and their application for effective clinical use. Furthermore, the modeling of thermoradiotherapy planning, which can be integrated with radiotherapy to provide combined hyperthermia and radiotherapy treatment planning strategies, are also discussed. This review may contribute to the effective development of thermoradiotherapy planning in clinics.
Collapse
|
10
|
Dobšíček Trefná H, Schmidt M, van Rhoon GC, Kok HP, Gordeyev SS, Lamprecht U, Marder D, Nadobny J, Ghadjar P, Abdel-Rahman S, Kukiełka AM, Strnad V, Hurwitz MD, Vujaskovic Z, Diederich CJ, Stauffer PR, Crezee J. Quality assurance guidelines for interstitial hyperthermia. Int J Hyperthermia 2019; 36:277-294. [PMID: 30676101 DOI: 10.1080/02656736.2018.1564155] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Quality assurance (QA) guidelines are essential to provide uniform execution of clinical hyperthermia treatments and trials. This document outlines the clinical and technical consequences of the specific properties of interstitial heat delivery and specifies recommendations for hyperthermia administration with interstitial techniques. Interstitial hyperthermia aims at tumor temperatures in the 40-44 °C range as an adjunct to radiation or chemotherapy. The clinical part of this document imparts specific clinical experience of interstitial heat delivery to various tumor sites as well as recommended interstitial hyperthermia workflow and procedures. The second part describes technical requirements for quality assurance of current interstitial heating equipment including electromagnetic (radiative and capacitive) and ultrasound heating techniques. Detailed instructions are provided on characterization and documentation of the performance of interstitial hyperthermia applicators to achieve reproducible hyperthermia treatments of uniform high quality. Output power and consequent temperature rise are the key parameters for characterization of applicator performance in these QA guidelines. These characteristics determine the specific maximum tumor size and depth that can be heated adequately. The guidelines were developed by the ESHO Technical Committee with participation of senior STM members and members of the Atzelsberg Circle.
Collapse
Affiliation(s)
- H Dobšíček Trefná
- a Department of Electrical Engineering , Chalmers University of Technology , Göteborg , Sweden
| | - M Schmidt
- b Department of Radiation Oncology , University Hospital Erlangen , Erlangen , Germany
| | - G C van Rhoon
- c Department of Radiation Oncology , Erasmus MC Cancer Institute , Rotterdam , the Netherlands
| | - H P Kok
- d Department of Radiation Oncology, Cancer Center Amsterdam , Amsterdam UMC, University of Amsterdam , Amsterdam , the Netherlands
| | - S S Gordeyev
- e Department of Colorectal Oncology , N.N.Blokhin Russian Cancer Research Center , Moscow, Russia
| | - U Lamprecht
- f Radioonkologische Klinik , Universitätsklinikum Tübingen , Tübingen , Germany
| | - D Marder
- g Kantonsspital Aarau , Radio-Onkologie-Zentrum KSA-KSB , Aarau , Switzerland
| | - J Nadobny
- h Klinik für Radioonkologie und Strahlentherapie , Charité Universitätsmedizin Berlin , Berlin , Germany
| | - P Ghadjar
- h Klinik für Radioonkologie und Strahlentherapie , Charité Universitätsmedizin Berlin , Berlin , Germany
| | - S Abdel-Rahman
- i Klinikum der Universität München-Campus Grosshadern , München , Germany
| | - A M Kukiełka
- j Department of Radiation Oncology , Centrum Diagnostyki i Terapii Onkologicznej Nu-Med , Zamość , Poland
| | - V Strnad
- b Department of Radiation Oncology , University Hospital Erlangen , Erlangen , Germany
| | - M D Hurwitz
- k Department of Radiation Oncology , Thomas Jefferson University , Philadelphia , PA , USA
| | - Z Vujaskovic
- l Department of Radiation Oncology , University of Maryland Baltimore , Baltimore , MD , USA
| | - C J Diederich
- m Department of Radiation Oncology , University of California , San Francisco , CA , USA
| | - P R Stauffer
- k Department of Radiation Oncology , Thomas Jefferson University , Philadelphia , PA , USA
| | - J Crezee
- d Department of Radiation Oncology, Cancer Center Amsterdam , Amsterdam UMC, University of Amsterdam , Amsterdam , the Netherlands
| |
Collapse
|