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Sample records for mri-guided hyperthermia treatment

  1. Controlled Hyperthermia with MRI-guided Focused Ultrasound

    DEFF Research Database (Denmark)

    Hokland, Steffen; Salomir, Rares; Pedersen, Michael

    Introduction: Hyperthermia is an appealing oncological treatment since the significant regions of hypoxia contained in most solid tumours are known to be sensitive to the cytotoxic effect of heat. However, due to the seemingly insurmountable technical difficulties associated with delivering thermal......-sensitive promoters and localized drug delivery using thermo-sensitive micro-carriers. Subjects Here we will present some of the recent advances in MRI-FUS, and their technical background. This will include: 1) Real-time MRI-thermometry. 2) FUS-technology. 3) Temporal and Spatial temperature control using MRI...... and penetration depth are governed by the wavelength. Hence for US it is possible to body non-invasively position sub-millimeter focal points in deep seated regions of the. Temperature Control: Most solid tumours cover volumes larger than that of the focal region. This problem may be reduced somewhat...

  2. Hyperthermia treatment planning

    International Nuclear Information System (INIS)

    Lagendijk, J.J.W.

    2000-01-01

    The development of hyperthermia, the treatment of tumours with elevated temperatures in the range of 40-44 deg. C with treatment times over 30 min, greatly benefits from the development of hyperthermia treatment planning. This review briefly describes the state of the art in hyperthermia technology, followed by an overview of the developments in hyperthermia treatment planning. It particularly highlights the significant problems encountered with heating realistic tissue volumes and shows how treatment planning can help in designing better heating technology. Hyperthermia treatment planning will ultimately provide information about the actual temperature distributions obtained and thus the tumour control probabilities to be expected. This will improve our understanding of the present clinical results of thermoradiotherapy and thermochemotherapy, and will greatly help both in optimizing clinical heating technology and in designing optimal clinical trials. (author)

  3. Feasibility of MRI-guided high intensity focused ultrasound treatment for adenomyosis

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Tien-Ying [State Key Laboratory of Ultrasound Engineering in Medicine, Department of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Zhang, Lian; Chen, Wenzhi [Clinical Center of Tumor Therapy of 2nd Affiliated Hospital of Chongqing Medical University, Chongqing 400010 (China); Liu, Yinjiang; He, Min; Huang, Xiu [State Key Laboratory of Ultrasound Engineering in Medicine, Department of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Orsi, Franco [Interventional Radiology Unit, European Institute of Oncology, 435 Via Ripamonti, 20141 Milan (Italy); Wang, Zhibiao, E-mail: wangzhibiao@haifu.com.cn [State Key Laboratory of Ultrasound Engineering in Medicine, Department of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Clinical Center of Tumor Therapy of 2nd Affiliated Hospital of Chongqing Medical University, Chongqing 400010 (China)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer We tested the feasibility of MRIgHIFU ablation for adenomyosis. Black-Right-Pointing-Pointer Patients were treated with MRIgHIFU under conscious sedation. Black-Right-Pointing-Pointer Patient symptoms were assessed using SSS and UFS-QOL. Black-Right-Pointing-Pointer The mean SSS and UFS-QOL showed significant improvements at follow up. Black-Right-Pointing-Pointer No serious complications were observed 62.5 {+-} 21.6. -- Abstract: Purpose: To test the feasibility of MRI-guided high intensity focused ultrasound ablation for adenomyosis. Materials and methods: Patients with symptomatic adenomyosis were treated with MRI-guided high intensity focused ultrasound (MRIgHIFU). Under conscious sedation, MRIgHIFU was performed by a clinical MRI-compatible focused ultrasound tumour therapeutic system (JM15100, Haifu{sup Registered-Sign} Technology Co. Ltd., Chongqing, China) which is combined with a 1.5 T MRI system (Magnetom Symphony, Siemens Healthcare, Erlangen, Germany). MRI was used to calculate the volume of the uterus and lesion. Non-perfused volume of the targeted lesions was evaluated immediately after MRIgHIFU. Patient symptoms were assessed using symptom severity score (SSS) and uterine fibroids symptoms and quality of life questionnaire (UFS-QOL). Results: Ten patients with mean age of 40.3 {+-} 4 years with an average lesion size of 56.9 {+-} 12.7 mm in diameter were treated. Non-perfused volume and the percentage of non-perfused volume obtained from contrast-enhanced T1 Magnetic resonance images immediately post-treatment were 66.6 {+-} 49.4 cm{sup 3} and 62.5 {+-} 21.6%, respectively. The mean SSS and UFS-QOL showed significant improvements of 25%, 16% and 25% at 3, 6 and 12 months follow up, respectively, to pre-treatment scores. No serious complications were observed. Conclusion: Based on the results from this study, MRIgHIFU treatment appears to be a safe and feasible modality to ablate adenomyosis lesion and

  4. SU-F-J-110: MRI-Guided Single-Session Simulation, Online Adaptation, and Treatment

    International Nuclear Information System (INIS)

    Hill, P; Geurts, M; Mittauer, K; Bayouth, J

    2016-01-01

    Purpose: To develop a combined simulation and treatment workflow for MRI-guided radiation therapy using the ViewRay treatment planning and delivery system. Methods: Several features of the ViewRay MRIdian planning and treatment workflows are used to simulate and treat patients that require emergent radiotherapy. A simple “pre-plan” is created on diagnostic imaging retrieved from radiology PACS, where conformal fields are created to target a volume defined by a physician based on review of the diagnostic images and chart notes. After initial consult in radiation oncology, the patient is brought to the treatment room, immobilized, and imaged in treatment position with a volumetric MR. While the patient rests on the table, the pre-plan is applied to the treatment planning MR and dose is calculated in the treatment geometry. After physician review, modification of the plan may include updating the target definition, redefining fields, or re-balancing beam weights. Once an acceptable treatment plan is finalized and approved, the patient is treated. Results: Careful preparation and judicious choices in the online planning process allow conformal treatment plans to be created and delivered in a single, thirty-minute session. Several advantages have been identified using this process as compared to conventional urgent CT simulation and delivery. Efficiency gains are notable, as physicians appreciate the predictable time commitment and patient waiting time for treatment is decreased. MR guidance in a treatment position offers both enhanced contrast for target delineation and reduction of setup uncertainties. The MRIdian system tools designed for adaptive radiotherapy are particularly useful, enabling plan changes to be made in minutes. Finally, the resulting plans, typically 6 conformal beams, are delivered as quickly as more conventional AP/PA beam arrangements with comparatively superior dose distributions. Conclusion: The ViewRay treatment planning software and

  5. Multicentre treatment planning study of MRI-guided brachytherapy for cervical cancer: Comparison between tandem-ovoid applicator users

    International Nuclear Information System (INIS)

    Nomden, Christel N.; Leeuw, Astrid A.C. de; Van Limbergen, Erik; Brabandere, Marisol de; Nulens, An; Nout, Remi A.; Laman, Mirjam; Ketelaars, Martijn; Lutgens, Ludovicus; Reniers, Brigitte; Jürgenliemk-Schulz, Ina Maria

    2013-01-01

    Background and purpose: To compare MRI-guided treatment planning approaches between four centres that use tandem-ovoid applicators. Material and methods: Four centres generated three treatment plans for four patients: standard, optimised intracavitary, and optimised intracavitary/interstitial. Prescribed D90 High-Risk CTV (HR-CTV) was 85 Gy EQD2 (external-beam radiotherapy and brachytherapy), while the D 2cc OAR limit was 90 Gy EQD2 for bladder and 75 Gy EQD2 for rectum, sigmoid, and bowel, respectively. DVH-parameters, source loading patterns and spatial dose distributions of the three treatment plans were compared. Results: The standard plans of the different centres were comparable with respect to the D90 HR-CTV, but differed in OAR doses. MRI-guided intracavitary optimisation resulted in organ sparing and smaller variation in DVH parameters between the centres. Adding interstitial needles led to target dose escalation while respecting the OAR constraints. However, substantial differences in relative weights of the applicator parts resulted in an increased variation in DVH parameters and locations of high dose regions. Conclusions: MRI-guided brachytherapy treatment planning optimisation provides the possibility to increase the dose to the HR-CTV and spare the OARs. Depending on the degree of conformity the centres make different choices in relative weighting of applicator parts, leading to different dose distributions

  6. On the improvement of regional hyperthermia treatment

    NARCIS (Netherlands)

    Kroeze, Hugo

    2002-01-01

    Hyperthermia is an adjuvant treatment modality to radiotherapy and/or chemotherapy, with the aim of increasing the tumour killing effect of the treatment. It involves the elevation of the tumour temperature to ~ 42oC. Radiofrequent heating is a practical method for hyperthermia: a number of

  7. Interstitial microwave hyperthermia treatment investigations

    International Nuclear Information System (INIS)

    Siauve, N; Lormel, C

    2012-01-01

    Microwave ablation also called interstitial hyperthermia is a medical procedure used in the treatment of many cancers, cardiac arrhythmias and other medical conditions. With this medical therapy, an electromagnetic source (antenna) is directly positioned in the target tissue and a sufficient power is injected to necrosis the tissue. The aim of this study is to propose a design procedure and develop the associated tools, for determining the optimal shape, dimensions, type and operating frequency of antenna according to the target volume. In this context, a 3D numerical predictive model of temperature elevation induced by the electric fields and two benches for thermal and electrical tissues properties characterization have been developed. To validate the procedure and the different tools, an experimental bench test which includes interstitial antenna, external microwave generator, phantom that represents the target tissue and measurement system of temperature and electric field has been elaborated.

  8. Feasibility of MRI-guided Focused Ultrasound as Organ-Sparing Treatment for Testicular Cancer

    Science.gov (United States)

    Staruch, Robert; Curiel, Laura; Chopra, Rajiv; Hynynen, Kullervo

    2009-04-01

    High cure rates for testicular cancer have prompted interest in organ-sparing surgery for patients with bilateral disease or single testis. Focused ultrasound (FUS) ablation could offer a noninvasive approach to organ-sparing surgery. The objective of this study was to determine the feasibility of using MR thermometry to guide organ-sparing focused ultrasound surgery in the testis. The testes of anesthetized rabbits were sonicated in several discrete locations using a single-element focused transducer operating at 2.787MHz. Focal heating was visualized with MR thermometry, using a measured PRF thermal coefficient of -0.0089±0.0003 ppm/° C. Sonications at 3.5-14 acoustic watts applied for 30 seconds produced maximum temperature elevations of 10-80° C, with coagulation verified by histology. Coagulation of precise volumes in the testicle is feasible with MRI-guided focused ultrasound. Variability in peak temperature for given sonication parameters suggests the need for online temperature feedback control.

  9. Treatment of hepatocellular carcinoma adjacent to large blood vessels using 1.5T MRI-guided percutaneous radiofrequency ablation combined with iodine-125 radioactive seed implantation

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Zheng-Yu, E-mail: linsinlan@yahoo.com.cn [The Department of Radiology, First Affiliated Hospital of Fujian Medical University, 20 Chazhong Road, Fuzhou 350005 (China); Chen, Jin, E-mail: snow8968851@163.com [The Department of Radiology, First Affiliated Hospital of Fujian Medical University, 20 Chazhong Road, Fuzhou 350005 (China); Deng, Xiu-Fen, E-mail: dxf197286@yahoo.com.cn [The Department of Radiology, First Affiliated Hospital of Fujian Medical University, 20 Chazhong Road, Fuzhou 350005 (China)

    2012-11-15

    Objective: The objective is to study the technology associated with and feasibility of the treatment of hepatocellular carcinoma (HCC) adjacent to large blood vessels using 1.5T MRI-guided radiofrequency ablation combined with iodine-125 (I-125) radioactive seed implantation. Methods: Sixteen patients with a total of 24 HCC lesions (average maximum diameter: 2.35 {+-} 1.03 cm) were pathologically confirmed by biopsy or clinically diagnosed received 1.5T MRI-guided percutaneous radiofrequency ablation (RFA) treatment. Each patient had one lesion adjacent to large blood vessels ({>=}3 mm); after the ablation, I-125 radioactive seeds were implanted in the portions of the lesions that were adjacent to the blood vessels. Results: All the ablations and I-125 radioactive seed implantations were successful; a total of 118 seeds were implanted. The ablated lesions exhibited hypointense signals on the T2WI sequence with a thin rim of hyperintense signals; they also exhibited significant hyperintense signals on the T1WI sequence with clear boundaries. The average follow-up period was 11.1 {+-} 6.2 months. There were 23 complete responses and one partial response in the 24 lesions. The alpha-fetoprotein (AFP) levels of the patients significantly decreased. Conclusion: The 1.5T MRI-guided RFA combined with I-125 radioactive seed implantation for the treatment of HCC adjacent to large blood vessels is an effective technology.

  10. Atlas-guided generation of pseudo-CT images for MRI-only and hybrid PET-MRI-guided radiotherapy treatment planning

    DEFF Research Database (Denmark)

    Arabi, H.; Koutsouvelis, N.; Rouzaud, M.

    2016-01-01

    Magnetic resonance imaging (MRI)-guided attenuation correction (AC) of positron emission tomography (PET) data and/or radiation therapy (RT) treatment planning is challenged by the lack of a direct link between MRI voxel intensities and electron density. Therefore, even if this is not a trivial t......-CT images from conventional Dixon MRI sequences with improved bone extraction accuracy. The approach is promising for potential use in PET AC and MRI-only or hybrid PET/MRI-guided RT treatment planning. © 2016 Institute of Physics and Engineering in Medicine.......Magnetic resonance imaging (MRI)-guided attenuation correction (AC) of positron emission tomography (PET) data and/or radiation therapy (RT) treatment planning is challenged by the lack of a direct link between MRI voxel intensities and electron density. Therefore, even if this is not a trivial...... the conventional MRI segmentation technique and a recently proposed multi-atlas approach. The clinical studies consisted of pelvic CT, PET and MRI scans of 12 patients with loco-regionally advanced rectal disease. In the first step, bone segmentation of the target image is optimized through local weighted atlas...

  11. An FDTD code for hyperthermia treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Marrocco, G.; Bardati, F. [Rome Univ. Tor Vergata (Italy). Dipt. di Informatica, sistemi e produzione; Tognolatti, P. [L' Aquila Univ. (Italy). Dipt. di Ingegneria Elettrica

    1999-08-01

    Radio-frequency hyperthermia is an anticancer modality based on the heating of tumours by radiating sources. A set of antennas is frequently used to enhance power depositions in tissues. Treatments planning needs electromagnetic field computation within realistic body models. Since several simulation may be required the optimize the antenna-body configuration, the electromagnetic solver should be designed in such a way that new configuration of the antenna set-up can be solved without heavy changes of the basic numerical code. In this paper a numerical investigation on the effects of a segmentation technique will be presented, with reference to an FDTD computation and the heating of a paediatric tumour.

  12. MRI-Guided Regional Personalized Electrical Stimulation in Multisession and Home Treatments

    Directory of Open Access Journals (Sweden)

    Andrea Cancelli

    2018-05-01

    Full Text Available The shape and position of the electrodes is a key factor for the efficacy of transcranial electrical stimulations (tES. We have recently introduced the Regional Personalized Electrode (RePE, a tES electrode fitting the personal cortical folding, that has been able to differentiate the stimulation of close by regions, in particular the primary sensory (S1 and motor (M1 cortices, and to personalize tES onto such an extended cortical district. However, neuronavigation on individual brain was compulsory for the correct montage. Here, we aimed at developing and testing a neuronavigation-free procedure for easy and quick positioning RePE, enabling multisession RePE-tES at home. We used off-line individual MRI to shape RePE via an ad-hoc computerized procedure, while an ad-hoc developed Adjustable Helmet Frame (AHF was used to properly position it in multisession treatments, even at home. We used neuronavigation to test the RePE shape and position obtained by the new computerized procedure and the re-positioning obtained via the AHF. Using Finite Element Method (FEM model, we also estimated the intra-cerebral current distribution induced by transcranial direct current stimulation (tDCS comparing RePE vs. non-RePE with fixed reference. Additionally, we tested, using FEM, various shapes, and positions of the reference electrode taking into account possible small displacements of RePE, to test feasibility of RePE-tES sessions at home. The new RePE neuronavigation-free positioning relies on brain MRI space distances, and produced a mean displacement of 3.5 ± 0.8 mm, and the re-positioning of 4.8 ± 1.1 mm. Higher electric field in S1 than in M1 was best obtained with the occipital reference electrode, a montage that proved to feature low sensitivity to typical RePE millimetric displacements. Additionally, a new tES accessory was developed to enable repositioning the electrodes over the scalp also at home, with a precision which is acceptable according to

  13. Porcine pilot study of MRI-guided HIFU treatment for neonatal intraventricular hemorrhage (IVH)

    Science.gov (United States)

    Looi, Thomas; Waspe, Adam; Mougenot, Charles; Amaral, Joao; Temple, Michael; Hynynen, Kullervo; Drake, James

    2012-11-01

    Intraventricular hemorrhage (IVH) occurs in 15% of premature babies and 50% of IVH cases progress to posthemorrhagic ventricular dilation due to large blood clots forming in the ventricles. Existing treatments such as tissue plasminogen activator (tPA) and surgical intervention have severe side effects in paediatric patients that include excessive bleeding and complications. This study investigates the feasibility of MR-HIFU for sonothrombolysis of blood clots from IVH using natural acoustic windows, known as fontanelles, in the skulls of newborns. The study involved 2 elements: a phantom study to examine beam limitations and acoustic properties, and an in-vivo porcine study. A phantom skull was created from sample patient data and was used to analyze reachability of the Philips Sonavelle system. Acoustic measurements of the phantom (attenuation of 5-14 dB and speed of sound of 1722-2965 m/s) indicated the phantom effectively mimics neonatal skull bone. For the ex-vivo studies, a porcine clot was created and sonicated for 5 mins at 500W with a 0.5% duty cycle. For the in-vivo experiment, a vertex craniotomy was performed and porcine blood was injected into the lateral ventricle under ultrasound guidance. Sonication using the prior parameters induced cavitation and post-sonication T1 and T2 images verified clot lysis. Further H&E analysis showed no presence of blood in the ventricles. These positive results show that MR-HIFU has potential as a noninvasive tool for sonothrombolysis of neonatal IVH clots.

  14. Hyperthermia for the Treatment of Locally Advanced Cervix Cancer

    NARCIS (Netherlands)

    M. Franckena (Martine)

    2010-01-01

    textabstract(English): There is a strong biological rationale for the use of hyperthermia as an oncological treatment modality. Fifteen randomized trials have shown significant improvement in clinical outcome when hyperthermia was added to radiotherapy, chemotherapy or both. At temperatures ≥ 40

  15. Morphologic alterations in normal and neoplastic tissues following hyperthermia treatment

    International Nuclear Information System (INIS)

    Badylak, S.F.; Babbs, C.F.

    1984-01-01

    The sequential morphologic alterations in normal skeletal muscle in rats, Walker 256 tumors in rats, and transmissible venereal tumors (TVT) in dogs following microwave-induced hyperthermia (43 0 C and 45 0 for 20 minutes) were studied by light and electron microscopy. Normal muscle and Walker 256 tumors showed vascular damage at 5 minutes post-heating (PH), followed by suppuration and thrombosis at 6 and 48 hours PH, and by regeneration and repair at 7 days PH. Endothelial damage and parenchymal degeneration were present 5 minutes PH. Progressive ischemic injury occurred for at least 48 hours PH. Two hyperthermia treatments, separated by a 30 or 60 minute cooling interval, were applied to rats implanted with Walker 256 tumors. Increased selective heating of tumor tissue versus surrounding normal tissue, and increased intratumoral temperatures were found during the second hyperthermia treatment. Canine TVTs were resistant to hyperthermia damage. These results characterized the sequential morphologic alterations following hyperthermia treatment and showed that: 1) vascular damage contributed to the immediate and latent cytotoxic effects of hyperthermia, 2) selective heating occurred in the neoplastic tissue disrupted by prior heat treatment, and 3) not all neoplasms are responsive to hyperthermia treatment

  16. Online Adaptive Hyperthermia Treatment Planning During Locoregional Heating to Suppress Treatment-Limiting Hot Spots

    NARCIS (Netherlands)

    Kok, H. Petra; Korshuize-van Straten, Linda; Bakker, Akke; de Kroon-Oldenhof, Rianne; Geijsen, Elisabeth D.; Stalpers, Lukas J. A.; Crezee, Johannes

    2017-01-01

    Adequate tumor temperatures during hyperthermia are essential for good clinical response, but excessive heating of normal tissue should be avoided. This makes locoregional heating using phased array systems technically challenging. Online application of hyperthermia treatment planning could help to

  17. MRI-Guided High–Dose-Rate Intracavitary Brachytherapy for Treatment of Cervical Cancer: The University of Pittsburgh Experience

    Energy Technology Data Exchange (ETDEWEB)

    Gill, Beant S.; Kim, Hayeon; Houser, Christopher J. [Department of Radiation Oncology, Magee-Womens Hospital of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States); Kelley, Joseph L.; Sukumvanich, Paniti; Edwards, Robert P.; Comerci, John T.; Olawaiye, Alexander B.; Huang, Marilyn; Courtney-Brooks, Madeleine [Department of Gynecologic Oncology, Magee-Womens Hospital of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States); Beriwal, Sushil, E-mail: beriwals@upmc.edu [Department of Radiation Oncology, Magee-Womens Hospital of University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States)

    2015-03-01

    Purpose: Image-based brachytherapy is increasingly used for gynecologic malignancies. We report early outcomes of magnetic resonance imaging (MRI)-guided brachytherapy. Methods and Materials: Consecutive patient cases with FIGO stage IB1 to IVA cervical cancer treated at a single institution were retrospectively reviewed. All patients received concurrent cisplatin with external beam radiation therapy along with interdigitated high–dose-rate intracavitary brachytherapy. Computed tomography or MRI was completed after each application, the latter acquired for at least 1 fraction. High-risk clinical target volume (HRCTV) and organs at risk were identified by Groupe Européen de Curiethérapie and European SocieTy for Radiotherapy and Oncology guidelines. Doses were converted to equivalent 2-Gy doses (EQD{sub 2}) with planned HRCTV doses of 75 to 85 Gy. Results: From 2007 to 2013, 128 patients, median 52 years of age, were treated. Predominant characteristics included stage IIB disease (58.6%) with a median tumor size of 5 cm, squamous histology (82.8%), and no radiographic nodal involvement (53.1%). Most patients (67.2%) received intensity modulated radiation therapy (IMRT) at a median dose of 45 Gy, followed by a median brachytherapy dose of 27.5 Gy (range, 25-30 Gy) in 5 fractions. At a median follow up of 24.4 months (range, 2.1-77.2 months), estimated 2-year local control, disease-free survival, and cancer-specific survival rates were 91.6%, 81.8%, and 87.6%, respectively. Predictors of local failure included adenocarcinoma histology (P<.01) and clinical response at 3 months (P<.01). Among the adenocarcinoma subset, receiving HRCTV D{sub 90} EQD{sub 2} ≥84 Gy was associated with improved local control (2-year local control rate 100% vs 54.5%, P=.03). Grade 3 or greater gastrointestinal or genitourinary late toxicity occurred at a 2-year actuarial rate of 0.9%. Conclusions: This study constitutes one of the largest reported series of MRI-guided

  18. Longitudinal diffusion MRI for treatment response assessment: Preliminary experience using an MRI-guided tri-cobalt 60 radiotherapy system.

    Science.gov (United States)

    Yang, Yingli; Cao, Minsong; Sheng, Ke; Gao, Yu; Chen, Allen; Kamrava, Mitch; Lee, Percy; Agazaryan, Nzhde; Lamb, James; Thomas, David; Low, Daniel; Hu, Peng

    2016-03-01

    To demonstrate the preliminary feasibility of a longitudinal diffusion magnetic resonance imaging (MRI) strategy for assessing patient response to radiotherapy at 0.35 T using an MRI-guided radiotherapy system (ViewRay). Six patients (three head and neck cancer, three sarcoma) who underwent fractionated radiotherapy were enrolled in this study. A 2D multislice spin echo single-shot echo planar imaging diffusion pulse sequence was implemented on the ViewRay system and tested in phantom studies. The same pulse sequence was used to acquire longitudinal diffusion data (every 2-5 fractions) on the six patients throughout the entire course of radiotherapy. The reproducibility of the apparent diffusion coefficient (ADC) measurements was assessed using reference regions and the temporal variations of the tumor ADC values were evaluated. In diffusion phantom studies, the ADC values measured on the ViewRay system matched well with reference ADC values with ViewRay MRI. Larger patient cohort studies are warranted to correlate the longitudinal diffusion measurements to patient outcomes. Such an approach may enable response-guided adaptive radiotherapy.

  19. Hyperthermia

    International Nuclear Information System (INIS)

    Perez, C.A.; Emami, B.; Nussbaum, G.; Sapareto, S.

    1987-01-01

    The effect on heat on malignant tumors was first reported by Hippocrates. In 1856 another described the disappearance of a soft tissue sarcoma following high fever in a patient with erysipelas. Later, another induced fever by injecting bacterial toxins, and others used localized hyperthermia to produce tumor regression in patients. There were 32 patients with advanced cancer of various types treated with a combination of heat, induced with pyrogenic substances, and x-ray therapy. Twenty-nine of these patients improved for 1 to 6 months. In the past 10 years interest has been rekindled to the clinical application of this modality because numerous papers have indicated that there may be a significant advantage to the use of heat alone or combined with irradiation and cytotoxic drugs to enhance the killing of tumor cells. The clinical use of heat has been hampered by a lack of adequate equipment to deliver effective heat in deep-seated lesions and of thermometry techniques that provide reliable information on heat distribution in target tissues. However, significant progress has been made. About 30% to 50% of patients with solid tumors have recurrences at the primary site. Many of these patients have regional lymph node recurrences. Both failure patterns could be improved if effective radiation sensitizers are developed

  20. Delineation of potential hot spots for hyperthermia treatment planning optimisation

    NARCIS (Netherlands)

    Wiersma, J.; van Wieringen, N.; Crezee, H.; van Dijk, J. D. P.

    2007-01-01

    The optimal feed parameters of the generators for a complex-phased hyperthermia array system consisting of 4, 8 or even more applicators cannot be found using only the expertise of the treatment staff or using the limited amount of field and temperature data obtained during treatment. A number of

  1. WE-FG-202-08: Assessment of Treatment Response Via Longitudinal Diffusion MRI On A MRI-Guided System: Initial Experience of Quantitative Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Qi, X; Yang, Y; Yang, L; Low, D; Sheng, K [UCLA, Los Angeles, CA (United States)

    2016-06-15

    Purpose: To report our initial experience of systematic monitoring treatment response using longitudinal diffusion MR images on a Co-60 MRI-guided radiotherapy system. Methods: Four patients, including 2 head-and-necks, 1 sarcoma and 1 GBM treated on a 0.35 Tesla MRI-guided treatment system, were analyzed. For each patient, 3D TrueFISP MRIs were acquired during CT simulation and before each treatment for treatment planning and patient setup purposes respectively. Additionally, 2D diffusion-weighted MR images (DWI) were acquired weekly throughout the treatment course. The gross target volume (GTV) and brainstem (as a reference structure) were delineated on weekly 3D TrueFISP MRIs to monitor anatomy changes, the contours were then transferred onto the corresponding DWI images after fusing with the weekly TrueFISP images. The patient-specific temporal and spatial variations during the entire treatment course, such as anatomic changes, target apparent diffusion coefficient (ADC) distribution were evaluated in a longitudinal pattern. Results: Routine MRI revealed progressive soft-tissue GTV volume changes (up to 53%) for the H&N cases during the treatment course of 5–7 weeks. Within the GTV, the mean ADC values varied from −44% (ADC decrease) to +26% (ADC increase) in a week. The gradual increase of ADC value was inversely associated with target volume variation for one H&N case. The maximal changes of mean ADC values within the brainstem were 5.3% for the H&N cases. For the large size sarcoma and GBM tumors, spatial heterogeneity and temporal variations were observed through longitudinal ADC analysis. Conclusion: In addition to the superior soft-tissue visualization, the 0.35T MR system on ViewRay showed the potential to quantitatively measure the ADC values for both tumor and normal tissues. For normal tissue that is minimally affected by radiation, its ADC values are reproducible. Tumor ADC values show temporal and spatial fluctuation that can be exploited for

  2. Iron oxide nanoparticle hyperthermia and chemotherapy cancer treatment

    Science.gov (United States)

    Petryk, A. A.; Giustini, A. J.; Ryan, P.; Strawbridge, R. R.; Hoopes, P. J.

    2009-02-01

    The benefit of combining hyperthermia and chemotherapy to treat cancer is well established. However, combined therapy has not yet achieved standard of care status. The reasons are numerous and varied, however the lack of significantly greater tumor cell sensitivity to heat (as compared to normal cells) and the inability to deliver heat to the tumor in a precise manner have been major factors. Iron oxide nanoparticle (IONP) hyperthermia, alone and combined with other modalities, offers a new direction in hyperthermia cancer therapy via improved tumor targeting and an improved therapeutic ratio. Our preliminary studies have demonstrated tumor cell cytotoxicity (in vitro and in vivo) with IONP heat and cisplatinum (CDDP) doses lower than those necessary when using conventional heating techniques or cisplatinum alone. Ongoing studies suggest such treatment could be further improved through the use of targeted nanoparticles.

  3. The effect of hyperthermia in the preoperative combined treatment of radiation, hyperthermia and chemotherapy for rectal carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Konishi, Fumio; Furuta, Kazuhiro; Saito, Yukio; Kataoka, Takashi; Kashiwagi, Hiroshi; Okada, Masaki; Kanazawa, Kyotaro; Sugahara, Tadashi; Shinohara, Naohiro (Jichi Medical School, Minamikawachi, Tochigi (Japan))

    1994-03-01

    To investigate the effectiveness of hyperthermia in the preoperative combined treatment of radiation, chemotherapy and hyperthermia for rectal carcinoma, two groups were compared. Group A consisted of 18 patients in whom hyperthermia, radiation and chemotherapy were performed. Group B consisted of 18 patients in whom only chemotherapy and radiation were performed. The total dose of radiation in both of the two groups was 40.5 Gy, and a radiation field covering the whole pelvis was used. Hyperthermia was performed using 8 MHz radiofrequency waves (Thermotron RF8, Yamamoto Vinyter, Japan), and tumors were heated at about 42 degrees C for 50 minutes. Hyperthermia was repeated five times during the preoperative treatment. Chemotherapy was performed by giving 5-fluorouracil suppositories to a total dose of 3400 mg. Mean tumor reduction rates on barium enema were 31.8% in group A and 18.2% in group B. The difference was statistically significant. The result of the histological assessment of tumor necrosis showed that there was a significantly higher degree of necrosis in group A than in group B. These results showed that the addition of hyperthermia enhanced tumor necrosis. It was concluded that the addition of hyperthermia would be an effective preoperative treatment of rectal carcinoma. (author).

  4. The effect of hyperthermia in the preoperative combined treatment of radiation, hyperthermia and chemotherapy for rectal carcinoma

    International Nuclear Information System (INIS)

    Konishi, Fumio; Furuta, Kazuhiro; Saito, Yukio; Kataoka, Takashi; Kashiwagi, Hiroshi; Okada, Masaki; Kanazawa, Kyotaro; Sugahara, Tadashi; Shinohara, Naohiro

    1994-01-01

    To investigate the effectiveness of hyperthermia in the preoperative combined treatment of radiation, chemotherapy and hyperthermia for rectal carcinoma, two groups were compared. Group A consisted of 18 patients in whom hyperthermia, radiation and chemotherapy were performed. Group B consisted of 18 patients in whom only chemotherapy and radiation were performed. The total dose of radiation in both of the two groups was 40.5 Gy, and a radiation field covering the whole pelvis was used. Hyperthermia was performed using 8 MHz radiofrequency waves (Thermotron RF8, Yamamoto Vinyter, Japan), and tumors were heated at about 42 degrees C for 50 minutes. Hyperthermia was repeated five times during the preoperative treatment. Chemotherapy was performed by giving 5-fluorouracil suppositories to a total dose of 3400 mg. Mean tumor reduction rates on barium enema were 31.8% in group A and 18.2% in group B. The difference was statistically significant. The result of the histological assessment of tumor necrosis showed that there was a significantly higher degree of necrosis in group A than in group B. These results showed that the addition of hyperthermia enhanced tumor necrosis. It was concluded that the addition of hyperthermia would be an effective preoperative treatment of rectal carcinoma. (author)

  5. SU-E-J-04: Integration of Interstitial High Intensity Therapeutic Ultrasound Applicators On a Clinical MRI-Guided High Intensity Focused Ultrasound Treatment Planning Software Platform

    Energy Technology Data Exchange (ETDEWEB)

    Ellens, N [Johns Hopkins University, Baltimore, Maryland (United States); Partanen, A [Philips Healthcare, Andover, Massachusetts (United States); Ghoshal, G; Burdette, E [Acoustic MedSystems Inc., Savoy, IL (United States); Farahani, K [National Cancer Institute, Bethesda, MD (United States)

    2015-06-15

    Purpose: Interstitial high intensity therapeutic ultrasound (HITU) applicators can be used to ablate tissue percutaneously, allowing for minimally-invasive treatment without ionizing radiation [1,2]. The purpose of this study was to evaluate the feasibility and usability of combining multielement interstitial HITU applicators with a clinical magnetic resonance imaging (MRI)-guided focused ultrasound software platform. Methods: The Sonalleve software platform (Philips Healthcare, Vantaa, Finland) combines anatomical MRI for target selection and multi-planar MRI thermometry to provide real-time temperature information. The MRI-compatible interstitial US applicators (Acoustic MedSystems, Savoy, IL, USA) had 1–4 cylindrical US elements, each 1 cm long with either 180° or 360° of active surface. Each applicator (4 Fr diameter, enclosed within a 13 Fr flexible catheter) was inserted into a tissue-mimicking agar-silica phantom. Degassed water was circulated around the transducers for cooling and coupling. Based on the location of the applicator, a virtual transducer overlay was added to the software to assist targeting and to allow automatic thermometry slice placement. The phantom was sonicated at 7 MHz for 5 minutes with 6–8 W of acoustic power for each element. MR thermometry data were collected during and after sonication. Results: Preliminary testing indicated that the applicator location could be identified in the planning images and the transducer locations predicted within 1 mm accuracy using the overlay. Ablation zones (thermal dose ≥ 240 CEM43) for 2 active, adjacent US elements ranged from 18 mm × 24 mm (width × length) to 25 mm × 25 mm for the 6 W and 8 W sonications, respectively. Conclusion: The combination of interstitial HITU applicators and this software platform holds promise for novel approaches in minimally-invasive MRI-guided therapy, especially when bony structures or air-filled cavities may preclude extracorporeal HIFU.[1] Diederich et al

  6. Thermosensitive Nanostructured Media for imaging and Hyperthermia Cancer Treatment

    Science.gov (United States)

    Martirosyan, Karen

    2011-03-01

    Hyperthermia has been used for many years to treat a wide variety of tumors in patients. The most commonly applied method of hyperthermia is capacitive heating by using microwave. Magnetic fluids based on iron oxide (Fe3O4), stabilized by biocompatible surfactants are typically used as heating agent. However, significant limitations of using commercial available magnetic particles are non-selectivity and overheating of surrounding normal tissues. To improve the efficacy of hyperthermia treatment we intend to develop Curie temperature (Tc)-tuned nanostructured media having T2 relaxation response on MRI for selective and self-controlled hyperthermia cancer treatment. As an active part of this media we fabricated superparamagnetic, biocompatible and dextran coated ferrite nanoparticles Mg1+xTixFe2(1-x)O4 at 0.3 x connected to a hydrocarbon chain, such as glycine, hydrazine, or urea. Our experiments revealed that ferrite with formula Mg1.35Ti0.35Fe1.3O4 appears with Curie temperature within 46-50rC. NSF, grant # 0933140.

  7. Less invasive causal treatment of ejaculatory duct obstruction by balloon dilation: a case report, literature review and suggestion of a CT- or MRI-guided intervention

    Directory of Open Access Journals (Sweden)

    Ole Kayser

    2012-03-01

    Full Text Available Uni- or bilateral ejaculatory duct obstruction (EDO is a rare but correctable cause of infertility, chronic pelvic pain and postejaculatory pain. EDO is a congenital or acquired condition, it is the underlying cause of infertility in approximately 5% of infertile men. If acquired, the etiology often remains unresolved, but prostatitis or urethritis with post-inflammatory adhesion of the duct walls seems to be a common underlying pathomechanism. Although a certain constellation of physicochemical semen parameters may lead to correct diagnosis, EDO often resembles a diagnosis by exclusion. Imaging of acquired EDO remains a challenge and the established surgical therapy, transurethral resection of the ejaculatory ducts (TURED, leads to a low rate of natural conception and a high rate of complications such as reflux of urine and epididymitis. We present a case of a male with suspected EDO who underwent a combined approach to both, semi-invasive diagnosis and therapy by transrectal puncture of the seminal vesicles and antegrade balloon-dilation of the ejaculatory ducts. Possibilities and pitfalls of this procedure are described and the literature is reviewed. Furthermore, we suggest a CT- or MRI-guided, percutaneous intervention for treatment of ejaculatory duct obstruction by balloon dilation and demonstrate initial steps of this procedure with a body donor. We call this new procedure PTED (percutaneous transgluteal ejaculatory ductoplasty.

  8. Technical Note: Dosimetric effects of couch position variability on treatment plan quality with an MRI-guided Co-60 radiation therapy machine

    Energy Technology Data Exchange (ETDEWEB)

    Chow, Phillip E., E-mail: pechow@mednet.ucla.edu; Thomas, David H.; Agazaryan, Nzhde; Cao, Minsong; Low, Daniel A.; Yang, Yingli; Steinberg, Michael L.; Lee, Percy; Lamb, James M. [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095 (United States)

    2016-08-15

    Purpose: Magnetic resonance imaging (MRI) guidance in radiation therapy brings real-time imaging and adaptive planning into the treatment vault where it can account for interfraction and intrafraction movement of soft tissue. The only commercially available MRI-guided radiation therapy device is a three-head {sup 60}Co and MRI system with an integrated treatment planning system (TPS). Couch attenuation of the beam of up to 20% is well modeled in the TPS. Variations in the patient’s day-to-day position introduce discrepancies in the actual couch attenuation as modeled in the treatment plan. For this reason, the authors’ institution avoids plans with beams that pass through or near the couch edges. This study investigates the effects of differential beam attenuation by the couch due to couch shifts in order to determine whether couch edge avoidance restrictions can be lifted. Couch shifts were simulated using a Monte Carlo treatment planning system and ion chamber measurements performed for validation. Methods: A total of 27 plans from 23 patients were investigated. Couch shifts of 1 and 2 cm were introduced in combinations of lateral and vertical directions to simulate patient position variations giving 16 shifted plans per reference plan. The 1 and 2 cm shifts were based on shifts recorded in 320 treatment fractions. Results: Following TG176 recommendations for measurement methods, couch attenuation measurements agreed with TPS modeled attenuation to within 2.1%. Planning target volume D95 changed less than 1% for 1 and 2 cm couch shifts in only the x-direction and less than 3% for all directions. Conclusions: Dosimetry of all plans tested was robust to couch shifts up to ±2 cm. In general, couch shifts resulted in clinically insignificant dosimetric deviations. It is conceivable that in certain cases with large systematic couch shifts and plans that are particularly sensitive to shifts, dosimetric changes might rise to a clinically significant level.

  9. First patients treated with a 1.5 T MRI-Linac: clinical proof of concept of a high-precision, high-field MRI guided radiotherapy treatment

    Science.gov (United States)

    Raaymakers, B. W.; Jürgenliemk-Schulz, I. M.; Bol, G. H.; Glitzner, M.; Kotte, A. N. T. J.; van Asselen, B.; de Boer, J. C. J.; Bluemink, J. J.; Hackett, S. L.; Moerland, M. A.; Woodings, S. J.; Wolthaus, J. W. H.; van Zijp, H. M.; Philippens, M. E. P.; Tijssen, R.; Kok, J. G. M.; de Groot-van Breugel, E. N.; Kiekebosch, I.; Meijers, L. T. C.; Nomden, C. N.; Sikkes, G. G.; Doornaert, P. A. H.; Eppinga, W. S. C.; Kasperts, N.; Kerkmeijer, L. G. W.; Tersteeg, J. H. A.; Brown, K. J.; Pais, B.; Woodhead, P.; Lagendijk, J. J. W.

    2017-12-01

    The integration of 1.5 T MRI functionality with a radiotherapy linear accelerator (linac) has been pursued since 1999 by the UMC Utrecht in close collaboration with Elekta and Philips. The idea behind this integrated device is to offer unrivalled, online and real-time, soft-tissue visualization of the tumour and the surroundings for more precise radiation delivery. The proof of concept of this device was given in 2009 by demonstrating simultaneous irradiation and MR imaging on phantoms, since then the device has been further developed and commercialized by Elekta. The aim of this work is to demonstrate the clinical feasibility of online, high-precision, high-field MRI guidance of radiotherapy using the first clinical prototype MRI-Linac. Four patients with lumbar spine bone metastases were treated with a 3 or 5 beam step-and-shoot IMRT plan. The IMRT plan was created while the patient was on the treatment table and based on the online 1.5 T MR images; pre-treatment CT was deformably registered to the online MRI to obtain Hounsfield values. Bone metastases were chosen as the first site as these tumors can be clearly visualized on MRI and the surrounding spine bone can be detected on the integrated portal imager. This way the portal images served as an independent verification of the MRI based guidance to quantify the geometric precision of radiation delivery. Dosimetric accuracy was assessed post-treatment from phantom measurements with an ionization chamber and film. Absolute doses were found to be highly accurate, with deviations ranging from 0.0% to 1.7% in the isocenter. The geometrical, MRI based targeting as confirmed using portal images was better than 0.5 mm, ranging from 0.2 mm to 0.4 mm. In conclusion, high precision, high-field, 1.5 T MRI guided radiotherapy is clinically feasible.

  10. Atlas-guided generation of pseudo-CT images for MRI-only and hybrid PET-MRI-guided radiotherapy treatment planning

    Science.gov (United States)

    Arabi, Hossein; Koutsouvelis, Nikolaos; Rouzaud, Michel; Miralbell, Raymond; Zaidi, Habib

    2016-09-01

    Magnetic resonance imaging (MRI)-guided attenuation correction (AC) of positron emission tomography (PET) data and/or radiation therapy (RT) treatment planning is challenged by the lack of a direct link between MRI voxel intensities and electron density. Therefore, even if this is not a trivial task, a pseudo-computed tomography (CT) image must be predicted from MRI alone. In this work, we propose a two-step (segmentation and fusion) atlas-based algorithm focusing on bone tissue identification to create a pseudo-CT image from conventional MRI sequences and evaluate its performance against the conventional MRI segmentation technique and a recently proposed multi-atlas approach. The clinical studies consisted of pelvic CT, PET and MRI scans of 12 patients with loco-regionally advanced rectal disease. In the first step, bone segmentation of the target image is optimized through local weighted atlas voting. The obtained bone map is then used to assess the quality of deformed atlases to perform voxel-wise weighted atlas fusion. To evaluate the performance of the method, a leave-one-out cross-validation (LOOCV) scheme was devised to find optimal parameters for the model. Geometric evaluation of the produced pseudo-CT images and quantitative analysis of the accuracy of PET AC were performed. Moreover, a dosimetric evaluation of volumetric modulated arc therapy photon treatment plans calculated using the different pseudo-CT images was carried out and compared to those produced using CT images serving as references. The pseudo-CT images produced using the proposed method exhibit bone identification accuracy of 0.89 based on the Dice similarity metric compared to 0.75 achieved by the other atlas-based method. The superior bone extraction resulted in a mean standard uptake value bias of  -1.5  ±  5.0% (mean  ±  SD) in bony structures compared to  -19.9  ±  11.8% and  -8.1  ±  8.2% achieved by MRI segmentation-based (water

  11. MRI-guided cryoablation of the posterior femoral cutaneous nerve for the treatment of neuropathy-mediated sitting pain

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Dharmdev H.; Thawait, Gaurav K.; Fritz, Jan [Johns Hopkins University School of Medicine, Section of Musculoskeletal Radiology, Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Del Grande, Filippo [Johns Hopkins University School of Medicine, Section of Musculoskeletal Radiology, Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Ospedale Regionale di Lugano, Servizio di Radiologia, Lugano, Ticino (Switzerland)

    2017-07-15

    Neuropathy of the posterior femoral cutaneous nerve may manifest as pain and paresthesia in the skin over the inferior buttocks, posterior thigh, and popliteal region. Current treatment options include physical and oral pain therapy, perineural injections, and surgical neurectomy. Perineural steroid injections may provide short-term pain relief; however, to our knowledge, there is currently no minimally invasive denervation procedure for sustained pain relief that could serve as an alternative to surgical neurectomy. Percutaneous cryoablation of nerves is a minimally invasive technique that induces a sustained nerve conduction block through temporary freezing of the neural layers. It can result in long-lasting pain relief, but has not been described for the treatment of neuropathy-mediated PFCN pain. We report a technique of MR-guided cryoablation of the posterior femoral cutaneous nerve resulting in successful treatment of PFCN-mediated sitting pain. Cryoablation of the posterior femoral cutaneous nerve seems a promising, minimally invasive treatment option that deserves further investigation. (orig.)

  12. MRI-guided cryoablation of the posterior femoral cutaneous nerve for the treatment of neuropathy-mediated sitting pain

    International Nuclear Information System (INIS)

    Joshi, Dharmdev H.; Thawait, Gaurav K.; Fritz, Jan; Del Grande, Filippo

    2017-01-01

    Neuropathy of the posterior femoral cutaneous nerve may manifest as pain and paresthesia in the skin over the inferior buttocks, posterior thigh, and popliteal region. Current treatment options include physical and oral pain therapy, perineural injections, and surgical neurectomy. Perineural steroid injections may provide short-term pain relief; however, to our knowledge, there is currently no minimally invasive denervation procedure for sustained pain relief that could serve as an alternative to surgical neurectomy. Percutaneous cryoablation of nerves is a minimally invasive technique that induces a sustained nerve conduction block through temporary freezing of the neural layers. It can result in long-lasting pain relief, but has not been described for the treatment of neuropathy-mediated PFCN pain. We report a technique of MR-guided cryoablation of the posterior femoral cutaneous nerve resulting in successful treatment of PFCN-mediated sitting pain. Cryoablation of the posterior femoral cutaneous nerve seems a promising, minimally invasive treatment option that deserves further investigation. (orig.)

  13. TH-CD-BRA-11: Implementation and Evaluation of a New 3D Dosimetry Protocol for Validating MRI Guided Radiation Therapy Treatments

    International Nuclear Information System (INIS)

    Mein, S; Rankine, L; Adamovics, J; Li, H; Oldham, M

    2016-01-01

    Purpose: To develop, evaluate and apply a novel high-resolution 3D remote dosimetry protocol for validation of MRI guided radiation therapy treatments (MRIdian by ViewRay™). We demonstrate the first application of the protocol (including two small but required new correction terms) utilizing radiochromic 3D plastic PRESAGE™ with optical-CT readout. Methods: A detailed study of PRESAGE™ dosimeters (2kg) was conducted to investigate the temporal and spatial stability of radiation induced optical density change (ΔOD) over 8 days. Temporal stability was investigated on 3 dosimeters irradiated with four equally-spaced square 6MV fields delivering doses between 10cGy and 300cGy. Doses were imaged (read-out) by optical-CT at multiple intervals. Spatial stability of ΔOD response was investigated on 3 other dosimeters irradiated uniformly with 15MV extended-SSD fields with doses of 15cGy, 30cGy and 60cGy. Temporal and spatial (radial) changes were investigated using CERR and MATLAB’s Curve Fitting Tool-box. A protocol was developed to extrapolate measured ΔOD readings at t=48hr (the typical shipment time in remote dosimetry) to time t=1hr. Results: All dosimeters were observed to gradually darken with time (<5% per day). Consistent intra-batch sensitivity (0.0930±0.002 ΔOD/cm/Gy) and linearity (R2=0.9996) was observed at t=1hr. A small radial effect (<3%) was observed, attributed to curing thermodynamics during manufacture. The refined remote dosimetry protocol (including polynomial correction terms for temporal and spatial effects, CT and CR) was then applied to independent dosimeters irradiated with MR-IGRT treatments. Excellent line profile agreement and 3D-gamma results for 3%/3mm, 10% threshold were observed, with an average passing rate 96.5%± 3.43%. Conclusion: A novel 3D remote dosimetry protocol is presented capable of validation of advanced radiation treatments (including MR-IGRT). The protocol uses 2kg radiochromic plastic dosimeters read-out by

  14. TH-CD-BRA-11: Implementation and Evaluation of a New 3D Dosimetry Protocol for Validating MRI Guided Radiation Therapy Treatments

    Energy Technology Data Exchange (ETDEWEB)

    Mein, S [Duke University Medical Physics Graduate Program (United States); Rankine, L [Department of Radiation Oncology, University of North Carolina in Chapel Hill (United States); Department of Radiation Oncology, Washington University School of Medicine (United States); Adamovics, J [Department of Chemistry and Biology, Rider University, Lawrenceville, NJ (United States); Li, H [Department of Radiation Oncology, Washington University School of Medicine (United States); Oldham, M [Department of Radiation Oncology, Duke University Medical Center (United States)

    2016-06-15

    Purpose: To develop, evaluate and apply a novel high-resolution 3D remote dosimetry protocol for validation of MRI guided radiation therapy treatments (MRIdian by ViewRay™). We demonstrate the first application of the protocol (including two small but required new correction terms) utilizing radiochromic 3D plastic PRESAGE™ with optical-CT readout. Methods: A detailed study of PRESAGE™ dosimeters (2kg) was conducted to investigate the temporal and spatial stability of radiation induced optical density change (ΔOD) over 8 days. Temporal stability was investigated on 3 dosimeters irradiated with four equally-spaced square 6MV fields delivering doses between 10cGy and 300cGy. Doses were imaged (read-out) by optical-CT at multiple intervals. Spatial stability of ΔOD response was investigated on 3 other dosimeters irradiated uniformly with 15MV extended-SSD fields with doses of 15cGy, 30cGy and 60cGy. Temporal and spatial (radial) changes were investigated using CERR and MATLAB’s Curve Fitting Tool-box. A protocol was developed to extrapolate measured ΔOD readings at t=48hr (the typical shipment time in remote dosimetry) to time t=1hr. Results: All dosimeters were observed to gradually darken with time (<5% per day). Consistent intra-batch sensitivity (0.0930±0.002 ΔOD/cm/Gy) and linearity (R2=0.9996) was observed at t=1hr. A small radial effect (<3%) was observed, attributed to curing thermodynamics during manufacture. The refined remote dosimetry protocol (including polynomial correction terms for temporal and spatial effects, CT and CR) was then applied to independent dosimeters irradiated with MR-IGRT treatments. Excellent line profile agreement and 3D-gamma results for 3%/3mm, 10% threshold were observed, with an average passing rate 96.5%± 3.43%. Conclusion: A novel 3D remote dosimetry protocol is presented capable of validation of advanced radiation treatments (including MR-IGRT). The protocol uses 2kg radiochromic plastic dosimeters read-out by

  15. Multimodal treatment combining chemotherapy, hyperthermia and radiotherapy for ovarian cancer

    International Nuclear Information System (INIS)

    Nagashima, Kei

    1992-01-01

    There has been increasing interest in the use of heat in the treatment of cancer. Theoretically cells are the most sensitive to ionizing radiation at mitosis, whereas the cycle phase that is the most resistant to ionizing radiation namely late in the DNA. Synthetic phase (late S) is the most sensitive to hyperthermia. Hyperthermia has been reported to enhance the cytocidal effects of several active chemotherapeutic agents. When thermal potentiation of chemotherapeutic agents against malignant cells is contemplated, normal tissues have a relatively high ambient blood flow which increases in response to thermal stress, thereby dissipating heat, compared to tumors. Tumors, with relatively poor blood flow and a responsive neovasculature, are in capable of augmenting flow and acting as a heat reservoir. This is the phenomenon of a heat reservoir which is one factor to enhance the cytocidal effects of several active anticancer agents for enhancing the uptake in tumor. The importance is in the adjuvant chemotherapy treated for post operative, advanced and recurrent ovarian cancer. Heating enhances the effects of radiotherapy and chemotherapy. Thirty patients with ovarian cancer were subjected to the multidisciplinary treatment with combination of hyperthermochemotherapy and radiation. The 30 patients consisted of 18 with endometrioid adenocarcinoma and 7 with serious post operative or recurrent status. Two types of equipments with rediofrequencies of 70 MHz (BSD-1000) or 434 MHZ (TAG MED·HS 434) were used for hyperthermia. Chemotherapeutic agents such as adriamycin, cis DDP, cyclophosphamide and etoposide were injected intravenously. Arterial infusion with reservoir was very effective in advanced stage of ovarian cancer. No severe or fatal side effects were observed. Hyperthermochemotherapy is useful and effective for the postoperative management or the treatment of recurrent cancer of the ovary. (J.P.N.)

  16. A novel hyperthermia treatment for bone metastases using magnetic materials

    International Nuclear Information System (INIS)

    Matsumine, Akihiko; Asanuma, Kunihiro; Matsubara, Takao; Nakamura, Tomoki; Uchida, Atsumasa; Sudo, Akihiro; Takegami, Kenji

    2011-01-01

    Patients with bone metastases in the extremities sometimes require surgical intervention to prevent deterioration of quality of life due to a pathological fracture. The use of localized radiotherapy combined with surgical reinforcement has been a gold standard for the treatment of bone metastases. However, radiotherapy sometimes induces soft tissue damage, including muscle induration and joint contracture. Moreover, cancer cells are not always radiosensitive. Hyperthermia has been studied since the 1940s using an experimental animal model to treat various types of advanced cancer, and studies have now reached the stage of clinical application, especially in conjunction with radiotherapy or chemotherapy. Nevertheless, bone metastases have several special properties which discourage oncologists from developing hyperthermic therapeutic strategies. First, the bone is located deep in the body, and has low thermal conductivity due to the thickness of cortical bone and the highly vascularized medulla. To address these issues, we developed new hyperthermic strategies which generate heat using magnetic materials under an alternating electromagnetic field, and started clinical application of this treatment modality. The purpose of this review is to summarize the latest studies on hyperthermic treatment in the field of musculoskeletal tumors, and to introduce the treatment strategy employing our novel hyperthermia approach. (author)

  17. Deep RF-hyperthermia: an effective treatment of advanced gliomas

    International Nuclear Information System (INIS)

    Sahinbas, H.; Groenemeyer, D.H.W.

    2005-01-01

    Full text: Contrary to the enormous efforts, results of conventional treatments of high-grade malignant gliomas are unsatisfactory. The prognosis of that tumor type is poor, its overall median survival time (MST) less than a year. Most of the cases are inoperable or only partially resectable, and their response to the various chemotherapies and/or radiotherapy is poor. The chemo-therapies which are successful for other locations often fail due to the effective brain-blood barrier (BBB). Probably the modification of the BBB by electromagnetic fields together with the direct electromagnetic-field heating are the main factors for the success of electro-hyperthermia. Primary aim of this study was to present the therapy tolerance for patients of electro-hyperthermia (EHY) for advanced malignant gliomas and as main intention to show the increase of the median survival time (MST). Our study was performed between 2000 - 2004; for patients with inoperable, partially resected or recurrent gliomas (WHO grade III and IV) with progression after radio- and/or chemotherapy and a Karnofsky Performance Score ≤30-40 %. 105 pts were involved in this study: 38 astrocytoma pts, 56 glioblastoma pts and 12 pts with other brain malignancies. All patients were heavily and unsatisfactory pretreated. EHY was applied over 4 weeks, 3 times a week over 1 hour in average by 100 Watt, as mono- or combined therapy (chemotherapy, irradiation therapy). The set of patients as well as the frequency of EHY was well documented for future evaluations. The historic reference of the MST from the first diagnosis for gliomas grade III and IV in our institute is 11.42 months (range 1-62), which is in good agreement with the relevant literature. The median survival time (MST) in our institute with EHY increases to 44.2 m, 23.2 m and 61.0 m for astrocytoma, glioblastoma and other brain malignancies, respectively. The therapy results were controlled by MRI images. EHY is a feasible treatment for advanced

  18. Infrared fibers for radiometer thermometry in hypothermia and hyperthermia treatment

    International Nuclear Information System (INIS)

    Katzir, A.; Bowman, H.F.; Asfour, Y.; Zur, A.; Valeri, C.R.

    1989-01-01

    Hypothermia is a condition which results from prolonged exposure to a cold environment. Rapid and efficient heating is needed to rewarm the patient from 32-35 degrees C to normal body temperature. Hyperthermia in cancer treatment involves heating malignant tumors to 42.5-43.0 degrees C for an extended period (e.g., 30 min) in an attempt to obtain remission. Microwave or radio frequency heating is often used for rewarming in hypothermia or for temperature elevation in hyperthermia treatment. One severe problem with such heating is the accurate measurement and control of temperature in the presence of a strong electromagnetic field. For this purpose, we have developed a fiberoptic radiometer system which is based on a nonmetallic, infrared fiber probe, which can operate either in contact or noncontact mode. In preliminary investigations, the radiometer worked well in a strong microwave or radiofrequency field, with an accuracy of +/- 0.5 degrees C. This fiberoptic thermometer was used to control the surface temperature of objects within +/- 2 degrees C

  19. Thermal dosimetry for bladder hyperthermia treatment. An overview.

    Science.gov (United States)

    Schooneveldt, Gerben; Bakker, Akke; Balidemaj, Edmond; Chopra, Rajiv; Crezee, Johannes; Geijsen, Elisabeth D; Hartmann, Josefin; Hulshof, Maarten C C M; Kok, H Petra; Paulides, Margarethus M; Sousa-Escandon, Alejandro; Stauffer, Paul R; Maccarini, Paolo F

    2016-06-01

    The urinary bladder is a fluid-filled organ. This makes, on the one hand, the internal surface of the bladder wall relatively easy to heat and ensures in most cases a relatively homogeneous temperature distribution; on the other hand the variable volume, organ motion, and moving fluid cause artefacts for most non-invasive thermometry methods, and require additional efforts in planning accurate thermal treatment of bladder cancer. We give an overview of the thermometry methods currently used and investigated for hyperthermia treatments of bladder cancer, and discuss their advantages and disadvantages within the context of the specific disease (muscle-invasive or non-muscle-invasive bladder cancer) and the heating technique used. The role of treatment simulation to determine the thermal dose delivered is also discussed. Generally speaking, invasive measurement methods are more accurate than non-invasive methods, but provide more limited spatial information; therefore, a combination of both is desirable, preferably supplemented by simulations. Current efforts at research and clinical centres continue to improve non-invasive thermometry methods and the reliability of treatment planning and control software. Due to the challenges in measuring temperature across the non-stationary bladder wall and surrounding tissues, more research is needed to increase our knowledge about the penetration depth and typical heating pattern of the various hyperthermia devices, in order to further improve treatments. The ability to better determine the delivered thermal dose will enable clinicians to investigate the optimal treatment parameters, and consequentially, to give better controlled, thus even more reliable and effective, thermal treatments.

  20. Multiple whole body hyperthermia treatments on normal beagles

    International Nuclear Information System (INIS)

    Geist, B.J.; Gillette, E.L.; Tucker, A.; Robertshaw, D.; Benjamin, S.A.; Macy, D.W.

    1985-01-01

    Twelve young adult male castrated beagles were randomized into either a treatment or a control group. The treatment group received 4 consecutive treatments at 1 week intertreatment intervals. A temperature and humidity controlled chamber was used to raise the core temperature to 42 0 C. Time required to raise the core temperature from 38 0 C to 42 0 C was approximately 70 minutes. Dogs were maintained at 42 0 C breathing halothane, 35% O/sub 2/ and 65 0 N/sub 2/ for 2 hours, followed by a 30 minute cool down period during which a shunt determination using 100% O/sub 2/ was done. No significant changes in temperature adjusted blood oxygen tension were noted during hyperthermia. Mean arterial blood pressure dropped an average of 15mm Hg during the 2 hour plateau. Cardiac rhythms remained stable and rates did not exceed 180 beats per minute. Central venous pressure remained stable and within normal range without treatment, 1.0 - 2.5 mm Hg. Dogs regained alertness and ambulation within 3 hours post treatment. No diarrhea was noted. The most significant acute changes appeared to be liver enzyme elevation, total protein decrement and transient changes in platelet and white blood cell counts

  1. Hyperthermia and radiotherapy

    International Nuclear Information System (INIS)

    Fitspatrick, C.

    1990-01-01

    Hyperthermia and radiotherapy have for long been used to assist in the control of tumours, either as separate entities, or, in a combined treatment scheme. This paper outlines why hyperthermia works, thermal dose and the considerations required in the timing when hyperthermia is combined with radiotherapy. Previously reported results for hyperthermia and radiotherapy used together are also presented. 8 refs., 8 tabs

  2. Non-Invasive Radiofrequency Field Treatment to Produce Hepatic Hyperthermia: Efficacy and Safety in Swine

    OpenAIRE

    ,; ,; ,; ,; ,; ,; ,; ,; ,

    2017-01-01

    The Kanzius non-invasive radio-frequency hyperthermia system (KNiRFH) has been investigated as a treatment option for hepatic hyperthermia cancer therapy. The treatment involves exposing the patient to an external high-power RF (13.56 MHz) electric field, whereby the propagating waves penetrate deep into the tumor causing targeted heating based on differential tissue dielectric properties. However, a comprehensive examination of the Kanzius system alongside any associated toxicities and its a...

  3. Mechanisms of hyperthermia induced radiatiosensitization for treatment of human papillomavirus positive tumors

    International Nuclear Information System (INIS)

    Oei, Arlene; Leeuwen, Caspar van; Stalpers, Lukas; Rodermond, Hans; Kok, Petra; Crezee, Hans; Franken, Nicolaas

    2016-01-01

    HPV is associated with cervical cancer, the third most common cancer in women. In over 70% of cervical cancers, the high-risk HPV-types 16 and 18 are found. In these tumors, functionality of p53 is suppressed by the presence of protein E6. Hyperthermia is a clinical application of heat in which tumour temperatures are raised to 40-43°C and combined hyperthermia with radiation is very effective in the treatment of cervical cancer

  4. Hyperthermia and PARP1-inhibition for sensitization of radiation and cisplatin treatment of cervical carcinoma cells

    International Nuclear Information System (INIS)

    Franken, Nicolaas; Oei, Arlene; Leeuwen, Caspar van; Stalpers, Lukas; Rodermond, Hans; Bel, Arjan; Kok, Petra; Crezee, Hans

    2014-01-01

    Ionizing radiation causes single and double strand breaks (SSBs and DSBs). DSBs are among the most critical DNA lesions and can be repaired via either non-homologous end joining (NHEJ) in which PARP1, Ku70 and DNA-PKcs are important, or homologous recombination (HR), where BRCA2 and Rad51 are essential. Hyperthermia disturbs HR by temporary inactivation of BRCA2. Cisplatin disrupts NHEJ and PARP1-inhibitor blocks Poly-(ADP-ribose)polymerase- 1, which is important in SSB repair, NHEJ and backup-NHEJ. Our goal was to investigate the additional effectiveness of hyperthermia and PARP1-inhibition on radiation and/or cisplatin treatment. Cervical carcinoma cells (SiHa) were treated at different temperature levels levels (41.0-43.0℃, PARP1-inhibitor (100 μM; NU1025), gamma-irradiation doses (0-8 Gy) or cisplatin (1'R for 1 h). Clonogenic assays were carried out to measure survival and γH2AX staining was used to visualize DSBs. To elucidate mechanisms of action expression levels of DNA repair proteins BRCA2 and DNA-PKcs were investigated after 42.0℃ (1 h) using western blot. Combined hyperthermia and radiation resulted in an increased number of γH2AX foci as compared to radiation alone. Hyperthermia treatment in combination with cisplatin and PARP1 inhibitor and with radiation and PARP1 inhibitor significantly decreased cell survival. Western blot demonstrated a decreased expression of BRCA2 protein at 30 min after hyperthermia treatment. Adding PARP1-inhibitor significantly improves the effectiveness of combined hyperthermia radiotherapy and combined hyperthermia-cisplatin treatment on cervical carcinoma cells. Hyperthermia affects DNA-DSB repair as is indicated by increased γH2AX foci numbers and decreased BRCA2 expression. (author)

  5. Findings in young pigs following combined treatment by hyperthermia and irradiation

    International Nuclear Information System (INIS)

    Schorcht, J.; Herrmann, T.; Barke, R.; Johannsen, U.

    1985-01-01

    In a pilot study, 8 store pigs were submitted to a combined treatment with hyperthermia (5 x 60 min; 42 0 C in the thoracic region) followed by telecobalt irradiation of the right lung (5 x 4 Gy). Radiologic checks of the thoracic organs and laboratory diagnostics provided useful data as to the temporal course of the radiogenic pulmonary affections and the tolerability of fractionated whole-body hyperthermia including superimposed local heating on store pigs. Histologic examinations of sections of heated and irradiated (right) as compared to exclusively heated (left) lung lobes of 4 animals suggested that hyperthermia exerted a radiosensitizing effect on the right lungs. Histologically confirmed irreversible lung fibrosis occurred there after exposure to even lower total doses following hyperthermia as compared to sole irradiation. (author)

  6. Online Adaptive Hyperthermia Treatment Planning During Locoregional Heating to Suppress Treatment-Limiting Hot Spots.

    Science.gov (United States)

    Kok, H Petra; Korshuize-van Straten, Linda; Bakker, Akke; de Kroon-Oldenhof, Rianne; Geijsen, Elisabeth D; Stalpers, Lukas J A; Crezee, Johannes

    2017-11-15

    Adequate tumor temperatures during hyperthermia are essential for good clinical response, but excessive heating of normal tissue should be avoided. This makes locoregional heating using phased array systems technically challenging. Online application of hyperthermia treatment planning could help to improve the heating quality. The aim of this study was to evaluate the clinical benefit of online treatment planning during treatment of pelvic tumors heated with the AMC-8 locoregional hyperthermia system. For online adaptive hyperthermia treatment planning, a graphical user interface was developed. Electric fields were calculated in a preprocessing step using our in-house-developed finite-difference-based treatment planning system. This allows instant calculation of the temperature distribution for user-selected phase-amplitude settings during treatment and projection onto the patient's computed tomographic scan for online visualization. Online treatment planning was used for 14 treatment sessions in 8 patients to reduce the patients' reports of hot spots while maintaining the same level of tumor heating. The predicted decrease in hot spot temperature should be at least 0.5°C, and the tumor temperature should decrease less than 0.2°C. These predictions were compared with clinical data: patient feedback about the hot spot and temperature measurements in the tumor region. In total, 17 hot spot reports occurred during the 14 sessions, and the alternative settings predicted the hot spot temperature to decrease by at least 0.5°C, which was confirmed by the disappearance of all 17 hot spot reports. At the same time, the average tumor temperature was predicted to change on average -0.01°C (range, -0.19°C to 0.34°C). The measured tumor temperature change was on average only -0.02°C (range, -0.26°C to 0.31°C). In only 2 cases the temperature decrease was slightly larger than 0.2°C, but at most it was 0.26°C. Online application of hyperthermia treatment planning is

  7. Local hyperthermia and artificial hyperglycemia in combined treatment of patients with rectum cancer

    International Nuclear Information System (INIS)

    Bezmen, V.A.; Illarionov, A.A.; Novokhrost, V.I.; Shilov, N.I.; Ospishchev, A.A.; Kejs, G.D.

    1990-01-01

    To study prospects of application of local hyperthermia, artificial hyperglycemia and radiotherapy in a preoperative period, 31 patients with rectum cancer were studied. The treatment included 3-hour artificial hyperglycemia first, then local SHF hyperthermia and telegamma irradiation using large-fractioned doses (ROD is 5 Gy, COD is 20 Gy). No serious side-effects were observed during the preoperative treatment period. The immediate and early results of combined treatment promise to improve the effectiveness of treatment of patients with rectum cancer. 3 refs

  8. The effect of hypofractionated radiation and magnetic nanoparticle hyperthermia on tumor immunogenicity and overall treatment response

    Science.gov (United States)

    Hoopes, P. Jack; Wagner, Robert J.; Song, Ailin; Osterberg, Bjorn; Gladstone, David J.; Bursey, Alicea A.; Fiering, Steven N.; Giustini, Andrew J.

    2017-02-01

    It is now known that many tumors develop molecular signals (immune checkpoint modulators) that inhibit an effective tumor immune response. New information also suggest that even well-known cancer treatment modalities such as radiation and hyperthermia generate potentially beneficial immune responses that have been blocked or mitigated by such immune checkpoints, or similar molecules. The cancer therapy challenge is to; a) identify these treatment-based immune signals (proteins, antigens, etc.); b) the treatment doses or regimens that produce them; and c) the mechanisms that block or have the potential to promote them. The goal of this preliminary study, using the B6 mouse - B16 tumor model, clinically relevant radiation doses and fractionation schemes (including those used clinically in hypofractionated radiation therapy), magnetic nanoparticle hyperthermia (mNPH) and sophisticated protein, immune and tumor growth analysis techniques and modulators, is to determine the effect of specific radiation or hyperthermia alone and combined on overall treatment efficacy and immunologic response mechanisms. Preliminary analysis suggests that radiation dose (10 Gy vs. 2 Gy) significantly alters the mechanism of cell death (apoptosis vs. mitosis vs. necrosis) and the resulting immunogenicity. Our hypothesis and data suggest this difference is protein/antigen and immune recognition-based. Similarly, our evidence suggest that radiation doses larger than the conventional 2 Gy dose and specific hyperthermia doses and techniques (including mNP hyperthermia treatment) can be immunologically different, and potentially superior to, the radiation and heat therapy regimens that are typically used in research and clinical practice.

  9. Ultrasound- and MRI-Guided Prostate Biopsy

    Science.gov (United States)

    ... assistance of a nurse and an MR imaging technologist. As with the ultrasound procedure, you may receive antibiotics, sedatives and pain medication before the biopsy. The MRI-guided procedure may use contrast ... A nurse or technologist will insert an intravenous (IV) catheter into a ...

  10. Hyperthermia generated by Foucault currents for oncological treatments with COMSOL

    International Nuclear Information System (INIS)

    Romero C, R. L.; Cordova F, T.; Basurto I, G.; Guzman C, R.; Castro L, J.

    2017-10-01

    The hyperthermia generated by variable magnetic fields is a promising power method for oncological therapy, because apoptosis is induced in tumor cells at temperatures between 42 and 45 degrees Celsius. It is known that an alternating magnetic field on the FeO 4 magnetite particles produces heat through three paths: is generated by parasitic currents, lost in hysteresis cycles and losses by magnetization relaxation; taking advantage of the energy losses through the joule effect and the transformation into heat, a simulation is shown in COMSOL about the temporal distribution of temperature in transformed biological systems, to have an estimate of the properties and behavior of the temperature gradient when magnetic hyperthermia is generated in human transformed tissue. (Author)

  11. The case for SAR as the major component of a hyperthermia treatment unit

    International Nuclear Information System (INIS)

    Scott, R.S.

    1985-01-01

    A major problem facing clinical hyperthermia is the lack of a useful unit of treatment. Most attempts at a treatment unit have utilized some function of temperature and time. Having accepted the validity of such a hypothetical units, one is faced with the formidable problem of obtaining a three dimensional temperature profile so that thermal dose can be determined. A corollary is the desirability of obtaining uniform temperature in the treatment volume. Various studies suggest that a uniform SAR is a more desirable goal when radiotherapy is to be used in combination with hyperthermia. The synergy between radiation and hyperthermia is maximized in low pH regions of tumor which are presumably also hypoxic. These regions are poorly perfused, likely to heat readily, and are resistant to the cytotoxic effects of radiation alone. On the other hand, well perfused regions of tumor are likely sensitive to radiation, and benefit less from the combination treatment. Other studies have definitely shown that tissue temperatures in the range normally associated with desirable hyperthermia treatment result in severe vascular damage. This damage could be expected to unnecessarily compromise the effectiveness of radiotherapy. Models in the literature can be combined to verify these observations

  12. Robust medical image segmentation for hyperthermia treatment planning

    International Nuclear Information System (INIS)

    Neufeld, E.; Chavannes, N.; Kuster, N.; Samaras, T.

    2005-01-01

    Full text: This work is part of an ongoing effort to develop a comprehensive hyperthermia treatment planning (HTP) tool. The goal is to unify all the steps necessary to perform treatment planning - from image segmentation to optimization of the energy deposition pattern - in a single tool. The bases of the HTP software are the routines and know-how developed in our TRINTY project that resulted the commercial EM platform SEMCAD-X. It incorporates the non-uniform finite-difference time-domain (FDTD) method, permitting the simulation of highly detailed models. Subsequently, in order to create highly resolved patient models, a powerful and robust segmentation tool is needed. A toolbox has been created that allows the flexible combination of various segmentation methods as well as several pre-and postprocessing functions. It works primarily with CT and MRI images, which it can read in various formats. A wide variety of segmentation methods has been implemented. This includes thresholding techniques (k-means classification, expectation maximization and modal histogram analysis for automatic threshold detection, multi-dimensional if required), region growing methods (with hysteretic behavior and simultaneous competitive growing), an interactive marker based watershed transformation, level-set methods (homogeneity and edge based, fast-marching), a flexible live-wire implementation as well as fuzzy connectedness. Due to the large number of tissues that need to be segmented for HTP, no methods that rely on prior knowledge have been implemented. Various edge extraction routines, distance transforms, smoothing techniques (convolutions, anisotropic diffusion, sigma filter...), connected component analysis, topologically flexible interpolation, image algebra and morphological operations are available. Moreover, contours or surfaces can be extracted, simplified and exported. Using these different techniques on several samples, the following conclusions have been drawn: Due to the

  13. The significance of accurate dielectric tissue data for hyperthermia treatment planning

    NARCIS (Netherlands)

    van de Kamer, JB; van Wieringen, N; de Leeuw, AAC; Lagendijk, JJW

    2001-01-01

    For hyperthermia treatment planning, dielectric properties of several tissue types are required. Since it is difficult to perform patient specific dielectric imaging, default values based on literature data are used. However, these show a large spread (approximate to 50%). Consequently, it is

  14. The significance of accurate dielectric tissue data for hyperthermia treatment planning

    NARCIS (Netherlands)

    van de Kamer, J. B.; van Wieringen, N.; de Leeuw, A. A.; Lagendijk, J. J.

    2001-01-01

    For hyperthermia treatment planning, dielectric properties of several tissue types are required. Since it is difficult to perform patient specific dielectric imaging, default values based on literature data are used. However, these show a large spread (approximately 50%). Consequently, it is

  15. SU-F-303-17: Real Time Dose Calculation of MRI Guided Co-60 Radiotherapy Treatments On Free Breathing Patients, Using a Motion Model and Fast Monte Carlo Dose Calculation

    International Nuclear Information System (INIS)

    Thomas, D; O’Connell, D; Lamb, J; Cao, M; Yang, Y; Agazaryan, N; Lee, P; Low, D

    2015-01-01

    Purpose: To demonstrate real-time dose calculation of free-breathing MRI guided Co−60 treatments, using a motion model and Monte-Carlo dose calculation to accurately account for the interplay between irregular breathing motion and an IMRT delivery. Methods: ViewRay Co-60 dose distributions were optimized on ITVs contoured from free-breathing CT images of lung cancer patients. Each treatment plan was separated into 0.25s segments, accounting for the MLC positions and beam angles at each time point. A voxel-specific motion model derived from multiple fast-helical free-breathing CTs and deformable registration was calculated for each patient. 3D images for every 0.25s of a simulated treatment were generated in real time, here using a bellows signal as a surrogate to accurately account for breathing irregularities. Monte-Carlo dose calculation was performed every 0.25s of the treatment, with the number of histories in each calculation scaled to give an overall 1% statistical uncertainty. Each dose calculation was deformed back to the reference image using the motion model and accumulated. The static and real-time dose calculations were compared. Results: Image generation was performed in real time at 4 frames per second (GPU). Monte-Carlo dose calculation was performed at approximately 1frame per second (CPU), giving a total calculation time of approximately 30 minutes per treatment. Results show both cold- and hot-spots in and around the ITV, and increased dose to contralateral lung as the tumor moves in and out of the beam during treatment. Conclusion: An accurate motion model combined with a fast Monte-Carlo dose calculation allows almost real-time dose calculation of a free-breathing treatment. When combined with sagittal 2D-cine-mode MRI during treatment to update the motion model in real time, this will allow the true delivered dose of a treatment to be calculated, providing a useful tool for adaptive planning and assessing the effectiveness of gated treatments

  16. Gold nanorod-mediated hyperthermia enhances the efficacy of HPMA copolymer-90Y conjugates in treatment of prostate tumors

    International Nuclear Information System (INIS)

    Buckway, Brandon; Frazier, Nick; Gormley, Adam J.; Ray, Abhijit; Ghandehari, Hamidreza

    2014-01-01

    Introduction: The treatment of prostate cancer using a radiotherapeutic 90 Y labeled N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer can be enhanced with localized tumor hyperthermia. An 111 In labeled HPMA copolymer system for single photon emission computerized tomography (SPECT) was developed to observe the biodistribution changes associated with hyperthermia. Efficacy studies were conducted in prostate tumor bearing mice using the 90 Y HPMA copolymer with hyperthermia. Methods: HPMA copolymers containing 1, 4, 7, 10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) were synthesized by reversible addition-fragmentation transfer (RAFT) copolymerization and subsequently labeled with either 111 In for imaging or 90 Y for efficacy studies. Radiolabel stability was characterized in vitro with mouse serum. Imaging and efficacy studies were conducted in DU145 prostate tumor bearing mice. Imaging was performed using single photon emission computerized tomography (SPECT). Localized mild tumor hyperthermia was achieved by plasmonic photothermal therapy using gold nanorods. Results: HPMA copolymer-DOTA conjugates demonstrated efficient labeling and stability for both radionuclides. Imaging analysis showed a marked increase of radiolabeled copolymer within the hyperthermia treated prostate tumors, with no significant accumulation in non-targeted tissues. The greatest reduction in tumor growth was observed in the hyperthermia treated tumors with 90 Y HPMA copolymer conjugates. Histological analysis confirmed treatment efficacy and safety. Conclusion: HPMA copolymer-DOTA conjugates radiolabeled with both the imaging and treatment radioisotopes, when combined with hyperthermia can serve as an image guided approach for efficacious treatment of prostate tumors

  17. Similarities and differences in ablative and non-ablative iron oxide nanoparticle hyperthermia cancer treatment

    Science.gov (United States)

    Petryk, Alicia A.; Misra, Adwiteeya; Kastner, Elliot J.; Mazur, Courtney M.; Petryk, James D.; Hoopes, P. Jack

    2015-03-01

    The use of hyperthermia to treat cancer is well studied and has utilized numerous delivery techniques, including microwaves, radio frequency, focused ultrasound, induction heating, infrared radiation, warmed perfusion liquids (combined with chemotherapy), and recently, metallic nanoparticles (NP) activated by near infrared radiation (NIR) and alternating magnetic field (AMF) based platforms. It has been demonstrated by many research groups that ablative temperatures and cytotoxicity can be produced with locally NP-based hyperthermia. Such ablative NP techniques have demonstrated the potential for success. Much attention has also been given to the fact that NP may be administered systemically, resulting in a broader cancer therapy approach, a lower level of tumor NP content and a different type of NP cancer therapy (most likely in the adjuvant setting). To use NP based hyperthermia successfully as a cancer treatment, the technique and its goal must be understood and utilized in the appropriate clinical context. The parameters include, but are not limited to, NP access to the tumor (large vs. small quantity), cancer cell-specific targeting, drug carrying capacity, potential as an ionizing radiation sensitizer, and the material properties (magnetic characteristics, size and charge). In addition to their potential for cytotoxicity, the material properties of the NP must also be optimized for imaging, detection and direction. In this paper we will discuss the differences between, and potential applications for, ablative and non-ablative magnetic nanoparticle hyperthermia.

  18. MRI-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture for treatment of cervical disc herniation: an initial experience

    International Nuclear Information System (INIS)

    Liu Ming; Li Chengli; Lu Yubo; Huang Jie; Song Jiqing; Li Lei; Bao Shougang; Cao Qianqian; Wu Lebin

    2010-01-01

    Objective: To explore the value of MR imaging-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture for treatment of cervical disc herniation. Methods: Eight herniated cervical discs in 7 patients were diagnosed by MRI, inclluding 5 discs of lateral protruding type, 2 discs of paramedian protruding type and one disc of central protruding type. All patients underwent MR imaging-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture. The procedures were guided by a set of 0.23 T open MR system mounted with iPath 200 optical tracking system. The herniated portion of the disc was punctured with a 14 G MR-comparible needle in the healthy side via anterolateral oblique route. The interventional steps were as follows: firstly, cut herniated part with percutaneous discectomy probe and inject 2ml oxygen-ozone mixture of 60 μg/ml; secondly, retreat the needle to the disc center, resect nucleus pulposus, and inject 2 ml oxygen-ozone mixture of 60 μg/ml; secondly, retreat the needle to the disc center, resect nucleus pulposus, and inject 2 ml oxygen-ozone mixture of 60 μg/ml. All patients were followed up for 6 months, with 4 patients by telephone and 3 patients in outpatient clinic. The effect of treatment was evaluated according to Williams postoperative assessment standard. Results: All procedures were performed successfully. The clinical outcome was evaluated as excellent in 5 cases, good in 1 cases and fair in 1 case. The total ratio of excellent and good was 85.7%. No serious complication occurred expect 1 case with intraoperative paroxysmal pain. Conclusion: MR imaging-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture was a safe, effective and minimally invasive method for the treatment of cervical disc herniation. (authors)

  19. Effect of tumor dose, volume and overall treatment time on local control after radiochemotherapy including MRI guided brachytherapy of locally advanced cervical cancer

    DEFF Research Database (Denmark)

    Tanderup, Kari; Fokdal, Lars Ulrik; Sturdza, Alina

    2016-01-01

    -center patient series (retroEMBRACE). Materials and methods This study analyzed 488 locally advanced cervical cancer patients treated with external beam radiotherapy ± chemotherapy combined with IGABT. Brachytherapy contouring and reporting was according to ICRU/GEC-ESTRO recommendations. The Cox Proportional...... Hazards model was applied to analyze the effect on local control of dose-volume metrics as well as overall treatment time (OTT), dose rate, chemotherapy, and tumor histology. Results With a median follow up of 46 months, 43 local failures were observed. Dose (D90) to the High Risk Clinical Target Volume...

  20. Optimizing deep hyperthermia treatments: are locations of patient pain complaints correlated with modelled SAR peak locations?

    Energy Technology Data Exchange (ETDEWEB)

    Canters, R A M; Franckena, M; Van der Zee, J; Van Rhoon, G C, E-mail: r.canters@erasmusmc.nl [Department of Radiation Oncology, Erasmus MC Daniel den Hoed Cancer Centre, Rotterdam, PO Box 5201, 3008 AE Rotterdam (Netherlands)

    2011-01-21

    During deep hyperthermia treatment, patient pain complaints due to heating are common when maximizing power. Hence, there exists a good rationale to investigate whether the locations of predicted SAR peaks by hyperthermia treatment planning (HTP) are correlated with the locations of patient pain during treatment. A retrospective analysis was performed, using the treatment reports of 35 patients treated with deep hyperthermia controlled by extensive treatment planning. For various SAR indicators, the average distance from a SAR peak to a patient discomfort location was calculated, for each complaint. The investigated V{sub 0.1closest} (i.e. the part of the 0.1th SAR percentile closest to the patient complaint) performed the best, and leads to an average distance between the SAR peak and the complaint location of 3.9 cm. Other SAR indicators produced average distances that were all above 10 cm. Further, the predicted SAR peak location with V{sub 0.1} provides a 77% match with the region of complaint. The current study demonstrates that HTP is able to provide a global indication of the regions where hotspots during treatment will most likely occur. Further development of this technology is necessary in order to use HTP as a valuable toll for objective and advanced SAR steering. The latter is especially valid for applications that enable 3D SAR steering.

  1. Optimizing deep hyperthermia treatments: are locations of patient pain complaints correlated with modelled SAR peak locations?

    International Nuclear Information System (INIS)

    Canters, R A M; Franckena, M; Van der Zee, J; Van Rhoon, G C

    2011-01-01

    During deep hyperthermia treatment, patient pain complaints due to heating are common when maximizing power. Hence, there exists a good rationale to investigate whether the locations of predicted SAR peaks by hyperthermia treatment planning (HTP) are correlated with the locations of patient pain during treatment. A retrospective analysis was performed, using the treatment reports of 35 patients treated with deep hyperthermia controlled by extensive treatment planning. For various SAR indicators, the average distance from a SAR peak to a patient discomfort location was calculated, for each complaint. The investigated V 0.1closest (i.e. the part of the 0.1th SAR percentile closest to the patient complaint) performed the best, and leads to an average distance between the SAR peak and the complaint location of 3.9 cm. Other SAR indicators produced average distances that were all above 10 cm. Further, the predicted SAR peak location with V 0.1 provides a 77% match with the region of complaint. The current study demonstrates that HTP is able to provide a global indication of the regions where hotspots during treatment will most likely occur. Further development of this technology is necessary in order to use HTP as a valuable toll for objective and advanced SAR steering. The latter is especially valid for applications that enable 3D SAR steering.

  2. Verification of hyperthermia treatment planning in cervix carcinoma patients using invasive thermometry

    International Nuclear Information System (INIS)

    Haaren Van, P.M.A.; Kok, H.P.; Zum Voerde Sive Voerding, P.J.; Oldenborg, S.; Stalpers, L.J.A.; Crezee, J.; Berg Van den, C.A.T; Leeuw De, A.A.C.

    2005-01-01

    Full text: Hyperthermia treatment planning (HTP) is a useful tool for improvement of clinical hyperthermia treatments. Aim of this study was to determine the correlation between HTP and measurements during hyperthermia treatments. We compared the calculated specific absorption rate (SAR) with clinically measured SAR-values, from ΔT-measurements, in cervix carcinoma patients. General difficulties for such clinical verifications are changes in the anatomy during the different steps and possible movement of the catheters. We used one fixed invasive catheter in the tumor additional to the usual non-invasive catheters in the vagina, bladder and rectum, for insertion of multisensor thermocouple probes. A special CT-scan with the patient in treatment position and the catheters in situ was made for the HTP. We performed these verifications in a total of 11 treatments in 7 patients. The main difficulties for accurate verification were of clinical nature: difficulties arising from the use of gynaecological tampon and the limited number of measurements in tissue. Remaining air in the vagina and sub-optimal tissue contact of the catheters resulted in bad thermal contact between thermocouples and tissue, causing measurement artefacts that are difficult to correlate with calculations. These artefacts are probably not specific for thermocouple measurements, but more general for intraluminal temperature and SAR measurements. (author)

  3. Formula to estimate the thermal enhancement ratio of a single simultaneous hyperthermia and radiation treatment

    International Nuclear Information System (INIS)

    Overgaard, J.

    1984-01-01

    An experimental model composed of a C 3 H mammary carcinoma and its surrounding skin has been exposed to simultaneous radiation and hyperthermia given with different combinations of the heating time and temperature. Based on the thermal enhancement ratio (TER) values obtained in the temperature range 41.5 to 43.5 0 C, a linear relationship between TER and the heating time was achieved at each temperature. The slopes of the curves drawn at each temperature were found to have a log-linear relationship with the treatment temperature. With these relationships it was possible to make a formula expressing the TER as a function of treatment temperature and time. This formula gives a crude but probably acceptable estimate of the TER following a single simultaneous radiation and heat treatment. Although subject to several limitations, the formula represents an attempt to describe a heat dose concept for the radiosensitizing effect of hyperthermia. This may be useful to establish the tolerance level of a given radiation treatment when combined with hyperthermia. (Auth.)

  4. Clinical use of the hyperthermia treatment planning system HyperPlan to predict effectiveness and toxicity

    International Nuclear Information System (INIS)

    Sreenivasa, Geetha; Gellermann, Johanna; Rau, Beate; Nadobny, Jacek; Schlag, Peter; Deuflhard, Peter; Felix, Roland; Wust, Peter

    2003-01-01

    Purpose: The main aim is to prove the clinical practicability of the hyperthermia treatment planning system HyperPlan on a β-test level. Data and observations obtained from clinical hyperthermia are compared with the numeric methods FE (finite element) and FDTD (finite difference time domain), respectively. Methods and Materials: The planning system HyperPlan is built on top of the modular, object-oriented platform for visualization and model generation AMIRA. This system already contains powerful algorithms for image processing, geometric modeling, and three-dimensional graphics display. A number of hyperthermia-specific modules are provided, enabling the creation of three-dimensional tetrahedral patient models suitable for treatment planning. Two numeric methods, FE and FDTD, are implemented in HyperPlan for solving Maxwell's equations. Both methods base their calculations on segmented (contour based) CT or MR image data. A tetrahedral grid is generated from the segmented tissue boundaries, consisting of approximately 80,000 tetrahedrons per patient. The FE method necessitates, primarily, this tetrahedral grid for the calculation of the E-field. The FDTD method, on the other hand, calculates the E-field on a cubical grid, but also requires a tetrahedral grid for correction at electrical interfaces. In both methods, temperature distributions are calculated on the tetrahedral grid by solving the bioheat transfer equation with the FE method. Segmentation, grid generation, E-field, and temperature calculation can be carried out in clinical practice at an acceptable time expenditure of about 1-2 days. Results: All 30 patients we analyzed with cervical, rectal, and prostate carcinoma exhibit a good correlation between the model calculations and the attained clinical data regarding acute toxicity (hot spots), prediction of easy-to-heat or difficult-to-heat patients, and the dependency on various other individual parameters. We could show sufficient agreement between

  5. Chemotherapy and Radiofrequency-Induced Mild Hyperthermia Combined Treatment of Orthotopic Pancreatic Ductal Adenocarcinoma Xenografts.

    Science.gov (United States)

    Krzykawska-Serda, Martyna; Agha, Mahdi S; Ho, Jason Chak-Shing; Ware, Matthew J; Law, Justin J; Newton, Jared M; Nguyen, Lam; Curley, Steven A; Corr, Stuart J

    2018-04-02

    Patients with pancreatic ductal adenocarcinomas (PDAC) have one of the poorest survival rates of all cancers. The main reason for this is related to the unique tumor stroma and poor vascularization of PDAC. As a consequence, chemotherapeutic drugs, such as nab-paclitaxel and gemcitabine, cannot efficiently penetrate into the tumor tissue. Non-invasive radiofrequency (RF) mild hyperthermia treatment was proposed as a synergistic therapy to enhance drug uptake into the tumor by increasing tumor vascular inflow and perfusion, thus, increasing the effect of chemotherapy. RF-induced hyperthermia is a safer and non-invasive technique of tumor heating compared to conventional contact heating procedures. In this study, we investigated the short- and long-term effects (~20 days and 65 days, respectively) of combination chemotherapy and RF hyperthermia in an orthotopic PDAC model in mice. The benefit of nab-paclitaxel and gemcitabine treatment was confirmed in mice; however, the effect of treatment was statistically insignificant in comparison to saline treated mice during long-term observation. The benefit of RF was minimal in the short-term and completely insignificant during long-term observation. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  6. Preparation and characterization of composite microspheres for brachytherapy and hyperthermia treatment of cancer

    International Nuclear Information System (INIS)

    Zhao Di; Huang Wenhai; Rahaman, Mohamed N.; Day, Delbert E.; Wang Deping; Gu Yifei

    2012-01-01

    Composite microspheres were prepared by coating yttrium–aluminum–silicate (YAS) glass microspheres (20–30 μm) with a layer of Fe 3 O 4 nanoparticles and evaluated for potential use in brachytherapy and hyperthermia treatment of cancer. After neutron activation to form the β-emitting 90 Y radionuclide, the composite microspheres can be injected into a patient to destroy cancerous tumors; at the same time, the composite microspheres can generate heat upon application of a magnetic field to also destroy the tumors. The results showed that the composite microspheres were chemically durable when immersed in a simulated body fluid (SBF), with ∼ 0.25% weight loss and ∼ 3.2% yttrium dissolved into the SBF after 30 days at 37 °C. The composite microspheres also showed ferromagnetic properties as a result of the Fe 3 O 4 coating; when immersed in water at 20 °C (20 mg in 1 mL of water), the application of an alternating magnetic field produced a temperature increase from 20 °C to 38−46 °C depending on the thickness of the Fe 3 O 4 coating. The results indicate that these composite microspheres have promising potential in combined brachytherapy and hyperthermia treatment of cancerous tumors. - Highlights: ► Composite microspheres for brachytherapy and hyperthermia treatment of cancer. ► Fe 3 O 4 nanoparticles coated on the yttrium–aluminum–silicate glass microspheres. ► Microspheres are chemically stable in SBF. ► Microspheres can generate heat for hyperthermia under an alternating magnetic field. ► Microspheres can emit β-rays for brachytherapy after neutron activation.

  7. Changes in tumor oxygenation during a combined treatment with fractionated irradiation and hyperthermia: an experimental study.

    Science.gov (United States)

    Zywietz, F; Reeker, W; Kochs, E

    1997-01-01

    To determine the influence of adjuvant hyperthermia on the oxygenation status of fractionated irradiated tumors. Oxygen partial pressure (pO2) in rat rhabdomyosarcomas (R1H) was measured sequentially at weekly intervals during a fractionated irradiation with 60Co-gamma-rays (60 Gy/20f/4 weeks) in combination with local hyperthermia (8 f(HT) at 43 degrees C, 1 h/4 weeks). Tumors were heated twice weekly with a 2450 MHz microwave device at 43 degrees C, 1 h starting 10 min after irradiation. The pO2 measurements (pO2-histograph, Eppendorf, Germany) were performed in anesthetized animals during mechanical ventilation and in hemodynamic steady state. All tumor pO2 measurements were correlated to measurements of the arterial oxygen partial pressure (paO2) determined by a blood gas analyzer. The oxygenation status of R1H tumors decreased continuously from the start of the combined treatment, with increasing radiation dose and number of heat fractions. In untreated controls a median tumor pO2 of 23 +/- 2 mmHg (mean +/- SEM) was measured. Tumor pO2 decreased to 11 +/- 2 mmHg after 30 Gy + 4 HT (2 weeks), and to 6 +/- 2 mmHg after 60 Gy + 8HT (4 weeks). The increase in the frequency of pO2-values below 5 mmHg and the decrease in the range of the pO2 histograms [delta p(10/90)] further indicated that tumor hypoxia increased relatively rapidly from the start of combined treatment. After 60 Gy + 8HT 48 +/- 5% (mean +/- SEM) of the pO2-values recorded were below 5 mmHg. These findings suggest that adjuvant hyperthermia to radiotherapy induces greater changes in tumor oxygenation than radiation alone [cf. (39)]. This might be of importance for the temporary application of hyperthermia in the course of a conventional radiation treatment.

  8. Non-Invasive Radiofrequency-Induced Targeted Hyperthermia for the Treatment of Hepatocellular Carcinoma

    Directory of Open Access Journals (Sweden)

    Mustafa Raoof

    2011-01-01

    Full Text Available Targeted biological therapies for hepatocellular cancer have shown minimal improvements in median survival. Multiple pathways to oncogenesis leading to rapid development of resistance to such therapies is a concern. Non-invasive radiofrequency field-induced targeted hyperthermia using nanoparticles is a radical departure from conventional modalities. In this paper we underscore the need for innovative strategies for the treatment of hepatocellular cancer, describe the central paradigm of targeted hyperthermia using non-invasive electromagnetic energy, review the process of characterization and modification of nanoparticles for the task, and summarize data from cell-based and animal-based models of hepatocellular cancer treated with non-invasive RF energy. Finally, future strategies and challenges in bringing this modality from bench to clinic are discussed.

  9. Simple and Rapid Synthesis of Magnetite/Hydroxyapatite Composites for Hyperthermia Treatments via a Mechanochemical Route

    Science.gov (United States)

    Iwasaki, Tomohiro; Nakatsuka, Ryo; Murase, Kenya; Takata, Hiroshige; Nakamura, Hideya; Watano, Satoru

    2013-01-01

    This paper presents a simple method for the rapid synthesis of magnetite/hydroxyapatite composite particles. In this method, superparamagnetic magnetite nanoparticles are first synthesized by coprecipitation using ferrous chloride and ferric chloride. Immediately following the synthesis, carbonate-substituted (B-type) hydroxyapatite particles are mechanochemically synthesized by wet milling dicalcium phosphate dihydrate and calcium carbonate in a dispersed suspension of magnetite nanoparticles, during which the magnetite nanoparticles are incorporated into the hydroxyapatite matrix. We observed that the resultant magnetite/hydroxyapatite composites possessed a homogeneous dispersion of magnetite nanoparticles, characterized by an absence of large aggregates. When this material was subjected to an alternating magnetic field, the heat generated increased with increasing magnetite concentration. For a magnetite concentration of 30 mass%, a temperature increase greater than 20 K was achieved in less than 50 s. These results suggest that our composites exhibit good hyperthermia properties and are promising candidates for hyperthermia treatments. PMID:23629669

  10. Simple and Rapid Synthesis of Magnetite/Hydroxyapatite Composites for Hyperthermia Treatments via a Mechanochemical Route

    Directory of Open Access Journals (Sweden)

    Tomohiro Iwasaki

    2013-04-01

    Full Text Available This paper presents a simple method for the rapid synthesis of magnetite/hydroxyapatite composite particles. In this method, superparamagnetic magnetite nanoparticles are first synthesized by coprecipitation using ferrous chloride and ferric chloride. Immediately following the synthesis, carbonate-substituted (B-type hydroxyapatite particles are mechanochemically synthesized by wet milling dicalcium phosphate dihydrate and calcium carbonate in a dispersed suspension of magnetite nanoparticles, during which the magnetite nanoparticles are incorporated into the hydroxyapatite matrix. We observed that the resultant magnetite/hydroxyapatite composites possessed a homogeneous dispersion of magnetite nanoparticles, characterized by an absence of large aggregates. When this material was subjected to an alternating magnetic field, the heat generated increased with increasing magnetite concentration. For a magnetite concentration of 30 mass%, a temperature increase greater than 20 K was achieved in less than 50 s. These results suggest that our composites exhibit good hyperthermia properties and are promising candidates for hyperthermia treatments.

  11. A system for the treatment of cancer by magnetically mediated arterial embolisation hyperthermia

    International Nuclear Information System (INIS)

    Jones, S.; Moroz, P.

    2002-01-01

    Full text: Sirtex Medical Limited is developing new technology to treat cancer by induced hyperthermia. A wealth of scientific data from laboratory and animal experimentation has shown that if the temperature of cancerous tissue is maintained for some time above about 42 deg C then that cancer will be destroyed. In current clinical practice, hyperthermia therapy is mostly used as an adjunct to radiotherapy in the treatment of superficial and other easily accessible tumour sites. Restrictions to the wider application of hyperthermia to the treatment of tumours located at deep body sites are technological in nature. There are presently no reliable non-invasive techniques that can be used to deliver an adequate heat dose to a deep seated tumour in an organ such as the liver without risking unacceptable heating of overlying and surrounding normal tissue. The Sirtex technology uses the heat generated in small magnetic particles when exposed to a high frequency magnetic field. The particles are delivered to the tumour via arterially infused microspheres which eventually embolise the tumour vasculature. The enhanced concentration of microspheres around the tumour ensures only the diseased tissue is heated. This paper reviews the current status of this research and presents recent experimental results including the differential heating and consequent destruction of experimental animal tumours. The pathway to clinical application will be discussed in light of these results

  12. Improvement of locoregional hyperthermia treatments of oesophageal cancer using treatment planning

    International Nuclear Information System (INIS)

    Kok, H.P.; Haaren Van, P.M.A.; Kamer Van de, J.B.; Zum Voerde Sive Voerding, P.J.; Wiersma, J.; Hulshof, M.C.C.M; Geijsen, E.D.; Crezee, J.

    2005-01-01

    Full text: The thermal dose achieved in the clinic often remains too low due to the incidence of treatment limiting hot spots, which are difficult to avoid intuitively due to the large number of degrees of freedom (amplitudes and phases) of the heating device. To improve hyperthermia treatments of oesophagus carcinoma patients with the 70 MHz AMC-4 waveguide system we performed hyperthermia treatment planning (HTP) with high resolution temperature based optimization. With this optimization we obtain amplitude (A) and phase (p) settings for the antennas for optimal tumor heating (> 43 o C) while preventing hot spots in normal tissue ( o C) and maintaining the spinal cord temperature below 40 o C to prevent neurotoxicity. With the mixed A/P settings the highest absolute ΔT's were achieved, while the ratio was not much different from the other two configurations. This implies that with these settings the same tumor heating can be obtained with less applied power, resulting in more efficient heating. The fact that the combined numerical A/clinical P settings resulted in the highest absolute temperature rises in the oesophagus might be due to the difference in patient positioning between the planning and the actual treatment, since the location of the SAR focus in the tumor is constructed mainly by phase steering. The temperature rise near the spinal cord depends mainly on the power of the top antenna. The correlation coefficient was R=0.37, which was considerably higher than the correlation with the powers or phases of the other antennas. The temperature rise in the oesophagus depends mainly on the power of the top and bottom antenna together. The correlation coefficient was only R=0.12 but this was still more than 2 times higher than the correlation with the power of the left and right antenna. The relation between the temperature rise due to a power pulse of 30 seconds and the achieved steady state temperature was more or less linear, implying a higher T 90 and T 50

  13. Improvement of locoregional hyperthermia treatments of oesophageal cancer using treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Kok, H P; Haaren Van, P M.A.; Kamer Van de, J B; Zum Voerde Sive Voerding, P.J.; Wiersma, J; Hulshof, M C.C.M; Geijsen, E D; Crezee, J [Department of Radiation Oncology, Academic Medical Center, University of Amsterdam (Netherlands)

    2005-07-01

    Full text: The thermal dose achieved in the clinic often remains too low due to the incidence of treatment limiting hot spots, which are difficult to avoid intuitively due to the large number of degrees of freedom (amplitudes and phases) of the heating device. To improve hyperthermia treatments of oesophagus carcinoma patients with the 70 MHz AMC-4 waveguide system we performed hyperthermia treatment planning (HTP) with high resolution temperature based optimization. With this optimization we obtain amplitude (A) and phase (p) settings for the antennas for optimal tumor heating (> 43 {sup o}C) while preventing hot spots in normal tissue (< 42 {sup o}C) and maintaining the spinal cord temperature below 40 {sup o}C to prevent neurotoxicity. With the mixed A/P settings the highest absolute {delta}T's were achieved, while the ratio was not much different from the other two configurations. This implies that with these settings the same tumor heating can be obtained with less applied power, resulting in more efficient heating. The fact that the combined numerical A/clinical P settings resulted in the highest absolute temperature rises in the oesophagus might be due to the difference in patient positioning between the planning and the actual treatment, since the location of the SAR focus in the tumor is constructed mainly by phase steering. The temperature rise near the spinal cord depends mainly on the power of the top antenna. The correlation coefficient was R=0.37, which was considerably higher than the correlation with the powers or phases of the other antennas. The temperature rise in the oesophagus depends mainly on the power of the top and bottom antenna together. The correlation coefficient was only R=0.12 but this was still more than 2 times higher than the correlation with the power of the left and right antenna. The relation between the temperature rise due to a power pulse of 30 seconds and the achieved steady state temperature was more or less linear

  14. MRI-guided and CT-guided cervical nerve root infiltration therapy. A cost comparison

    Energy Technology Data Exchange (ETDEWEB)

    Maurer, M.H.; Froeling, V.; Roettgen, R.; Bucourt, M. de; Hamm, B.; Streitparth, F. [Charite University Medicine Berlin (Germany). Dept. of Diagnostic and Interventional Radiology; Bretschneider, T. [Magdeburg Univ. (Germany). Dept. of Radiology and Nuclear Medicine; Hartwig, T.; Disch, A.C. [Charite University Medicine Berlin (Germany). Center for Musculoskeletal Surgery

    2014-06-15

    Purpose: To evaluate and compare the costs of MRI-guided and CT-guided cervical nerve root infiltration for the minimally invasive treatment of radicular neck pain. Materials and Methods: Between September 2009 and April 2012, 22 patients (9 men, 13 women; mean age: 48.2 years) underwent MRI-guided (1.0 Tesla, Panorama HFO, Philips) single-site periradicular cervical nerve root infiltration with 40 mg triamcinolone acetonide. A further 64 patients (34 men, 30 women; mean age: 50.3 years) were treated under CT fluoroscopic guidance (Somatom Definition 64, Siemens). The mean overall costs were calculated as the sum of the prorated costs of equipment use (purchase, depreciation, maintenance, and energy costs), personnel costs and expenditure for disposables that were identified for MRI- and CT-guided procedures. Additionally, the cost of ultrasound guidance was calculated. Results: The mean intervention time was 24.9 min. (range: 12-36 min.) for MRI-guided infiltration and 19.7 min. (range: 5-54 min.) for CT-guided infiltration. The average total costs per patient were EUR 240 for MRI-guided interventions and EUR 124 for CT-guided interventions. These were (MRI/CT guidance) EUR 150/60 for equipment use, EUR 46/40 for personnel, and EUR 44/25 for disposables. The mean overall cost of ultrasound guidance was EUR 76. Conclusion: Cervical nerve root infiltration using MRI guidance is still about twice as expensive as infiltration using CT guidance. However, since it does not involve radiation exposure for patients and personnel, MRI-guided nerve root infiltration may become a promising alternative to the CT-guided procedure, especially since a further price decrease is expected for MRI devices and MR-compatible disposables. In contrast, ultrasound remains the less expensive method for nerve root infiltration guidance. (orig.)

  15. MRI-guided and CT-guided cervical nerve root infiltration therapy. A cost comparison

    International Nuclear Information System (INIS)

    Maurer, M.H.; Froeling, V.; Roettgen, R.; Bucourt, M. de; Hamm, B.; Streitparth, F.; Bretschneider, T.; Hartwig, T.; Disch, A.C.

    2014-01-01

    Purpose: To evaluate and compare the costs of MRI-guided and CT-guided cervical nerve root infiltration for the minimally invasive treatment of radicular neck pain. Materials and Methods: Between September 2009 and April 2012, 22 patients (9 men, 13 women; mean age: 48.2 years) underwent MRI-guided (1.0 Tesla, Panorama HFO, Philips) single-site periradicular cervical nerve root infiltration with 40 mg triamcinolone acetonide. A further 64 patients (34 men, 30 women; mean age: 50.3 years) were treated under CT fluoroscopic guidance (Somatom Definition 64, Siemens). The mean overall costs were calculated as the sum of the prorated costs of equipment use (purchase, depreciation, maintenance, and energy costs), personnel costs and expenditure for disposables that were identified for MRI- and CT-guided procedures. Additionally, the cost of ultrasound guidance was calculated. Results: The mean intervention time was 24.9 min. (range: 12-36 min.) for MRI-guided infiltration and 19.7 min. (range: 5-54 min.) for CT-guided infiltration. The average total costs per patient were EUR 240 for MRI-guided interventions and EUR 124 for CT-guided interventions. These were (MRI/CT guidance) EUR 150/60 for equipment use, EUR 46/40 for personnel, and EUR 44/25 for disposables. The mean overall cost of ultrasound guidance was EUR 76. Conclusion: Cervical nerve root infiltration using MRI guidance is still about twice as expensive as infiltration using CT guidance. However, since it does not involve radiation exposure for patients and personnel, MRI-guided nerve root infiltration may become a promising alternative to the CT-guided procedure, especially since a further price decrease is expected for MRI devices and MR-compatible disposables. In contrast, ultrasound remains the less expensive method for nerve root infiltration guidance. (orig.)

  16. Automatic tissue segmentation of head and neck MR images for hyperthermia treatment planning

    International Nuclear Information System (INIS)

    Fortunati, Valerio; Niessen, Wiro J; Veenland, Jifke F; Van Walsum, Theo; Verhaart, René F; Paulides, Margarethus M

    2015-01-01

    A hyperthermia treatment requires accurate, patient-specific treatment planning. This planning is based on 3D anatomical models which are generally derived from computed tomography. Because of its superior soft tissue contrast, magnetic resonance imaging (MRI) information can be introduced to improve the quality of these 3D patient models and therefore the treatment planning itself. Thus, we present here an automatic atlas-based segmentation algorithm for MR images of the head and neck.Our method combines multiatlas local weighting fusion with intensity modelling. The accuracy of the method was evaluated using a leave-one-out cross validation experiment over a set of 11 patients for which manual delineation were available.The accuracy of the proposed method was high both in terms of the Dice similarity coefficient (DSC) and the 95th percentile Hausdorff surface distance (HSD) with median DSC higher than 0.8 for all tissues except sclera. For all tissues, except the spine tissues, the accuracy was approaching the interobserver agreement/variability both in terms of DSC and HSD. The positive effect of adding the intensity modelling to the multiatlas fusion decreased when a more accurate atlas fusion method was used.Using the proposed approach we improved the performance of the approach previously presented for H and N hyperthermia treatment planning, making the method suitable for clinical application. (paper)

  17. Automatic tissue segmentation of head and neck MR images for hyperthermia treatment planning

    Science.gov (United States)

    Fortunati, Valerio; Verhaart, René F.; Niessen, Wiro J.; Veenland, Jifke F.; Paulides, Margarethus M.; van Walsum, Theo

    2015-08-01

    A hyperthermia treatment requires accurate, patient-specific treatment planning. This planning is based on 3D anatomical models which are generally derived from computed tomography. Because of its superior soft tissue contrast, magnetic resonance imaging (MRI) information can be introduced to improve the quality of these 3D patient models and therefore the treatment planning itself. Thus, we present here an automatic atlas-based segmentation algorithm for MR images of the head and neck. Our method combines multiatlas local weighting fusion with intensity modelling. The accuracy of the method was evaluated using a leave-one-out cross validation experiment over a set of 11 patients for which manual delineation were available. The accuracy of the proposed method was high both in terms of the Dice similarity coefficient (DSC) and the 95th percentile Hausdorff surface distance (HSD) with median DSC higher than 0.8 for all tissues except sclera. For all tissues, except the spine tissues, the accuracy was approaching the interobserver agreement/variability both in terms of DSC and HSD. The positive effect of adding the intensity modelling to the multiatlas fusion decreased when a more accurate atlas fusion method was used. Using the proposed approach we improved the performance of the approach previously presented for H&N hyperthermia treatment planning, making the method suitable for clinical application.

  18. Long-Term Improvement in Treatment Outcome After Radiotherapy and Hyperthermia in Locoregionally Advanced Cervix Cancer: An Update of the Dutch Deep Hyperthermia Trial

    International Nuclear Information System (INIS)

    Franckena, Martine; Stalpers, Lukas J.A.; Koper, Peter C.M.; Wiggenraad, Ruud G.J.; Hoogenraad, Wim J.; Dijk, Jan D.P. van; Warlam-Rodenhuis, Carla C.; Jobsen, Jan J.; Rhoon, Gerard C. van; Zee, Jacoba van der

    2008-01-01

    Purpose: The local failure rate in patients with locoregionally advanced cervical cancer is 41-72% after radiotherapy (RT) alone, whereas local control is a prerequisite for cure. The Dutch Deep Hyperthermia Trial showed that combining RT with hyperthermia (HT) improved 3-year local control rates of 41-61%, as we reported earlier. In this study, we evaluate long-term results of the Dutch Deep Hyperthermia Trial after 12 years of follow-up. Methods and Materials: From 1990 to 1996, a total of 114 women with locoregionally advanced cervical carcinoma were randomly assigned to RT or RT + HT. The RT was applied to a median total dose of 68 Gy. The HT was given once weekly. The primary end point was local control. Secondary end points were overall survival and late toxicity. Results: At the 12-year follow-up, local control remained better in the RT + HT group (37% vs. 56%; p = 0.01). Survival was persistently better after 12 years: 20% (RT) and 37% (RT + HT; p = 0.03). World Health Organization (WHO) performance status was a significant prognostic factor for local control. The WHO performance status, International Federation of Gynaecology and Obstetrics (FIGO) stage, and tumor diameter were significant for survival. The benefit of HT remained significant after correction for these factors. European Organization for Research and Treatment of Cancer Grade 3 or higher radiation-induced late toxicities were similar in both groups. Conclusions: For locoregionally advanced cervical cancer, the addition of HT to RT resulted in long-term major improvement in local control and survival without increasing late toxicity. This combined treatment should be considered for patients who are unfit to receive chemotherapy. For other patients, the optimal treatment strategy is the subject of ongoing research

  19. Real-time MRI-guided percutaneous sclerotherapy of low-flow head and neck lymphatic malformations in the pediatric population - a stepwise approach

    Energy Technology Data Exchange (ETDEWEB)

    Partovi, Sasan; Vidal, Lorenna; Lu, Ziang; Nakamoto, Dean A.; Buethe, Ji; Clampitt, Mark; Coffey, Michael; Patel, Indravadan J. [University Hospitals Cleveland Medical Center, Case Western Reserve University, Department of Radiology, Section of Vascular and Interventional Radiology, Cleveland, OH (United States)

    2017-05-15

    Real-time MRI-guided percutaneous sclerotherapy is a novel and evolving treatment for congenital lymphatic malformations in the head and neck. We elaborate on the specific steps necessary to perform an MRI-guided percutaneous sclerotherapy of lymphatic malformations including pre-procedure patient work-up and preparation, stepwise intraprocedural interventional techniques and post-procedure management. Based on our institutional experience, MRI-guided sclerotherapy with a doxycycline-gadolinium-based mixture as a sclerosant for lymphatic malformations of the head and neck region in children is well tolerated and effective. (orig.)

  20. THE FIRST EXPERIENCE OF USING LOCAL HYPERTHERMIA IN COMBINED MODALITY TREATMENT OF OPERABLE NON-SMALL CELL LUNG CANCER

    Directory of Open Access Journals (Sweden)

    A. Yu. Dobrodeev

    2015-01-01

    Full Text Available The paper presents the first experience in treating 5 patients with stage II–III non-small cell lung cancer using combined modality treatment including 40 Gy preoperative hyperfractionated radiotherapy with concurrent 2 cycles of paclitaxel/carboplatin chemotherapy and local hyperthermia (10 sessions followed by radical surgery. The overal response rate to preoperative treatment was 80 %. Chemotherapy was well tolerated and hyperthermia resulted no in adverse effects. All patients underwent surgery (4 lobectomies and 1 pneumonectomy. No complications were observed in the postoperative period. The follow-up period ranged from 6 to 20 months. No evidence of disease progression and radiation-induced damages were observed.

  1. Safety and efficacy of targeted hyperthermia treatment utilizing gold nanorod therapy in spontaneous canine neoplasia.

    Science.gov (United States)

    Schuh, Elizabeth M; Portela, Roberta; Gardner, Heather L; Schoen, Christian; London, Cheryl A

    2017-10-02

    Hyperthermia is an established anti-cancer treatment but is limited by tolerance of adjacent normal tissues. Parenteral administration of gold nanorods (NRs) as a photosensitizer amplifies the effects of hyperthermia treatment while sparing normal tissues. This therapy is well tolerated and has demonstrated anti-tumor effects in mouse models. The purpose of this phase 1 study was to establish the safety and observe the anti-tumor impact of gold NR enhanced (plasmonic) photothermal therapy (PPTT) in client owned canine patients diagnosed with spontaneous neoplasia. Seven dogs underwent gold NR administration and subsequent NIR PPTT. Side effects were mild and limited to local reactions to NIR laser. All of the dogs enrolled in the study experienced stable disease, partial remission or complete remission. The overall response rate (ORR) was 28.6% with partial or complete remission of tumors at study end. PPTT utilizing gold nanorod therapy can be safely administered to canine patients. Further studies are needed to determine the true efficacy in a larger population of canine cancer patients and to and identify those patients most likely to benefit from this therapy.

  2. MRI guided stereotactic ventrointermediate thalamotomy for writer's cramp: two cases report and literature review

    Directory of Open Access Journals (Sweden)

    Chao-shi NIU

    2015-10-01

    Full Text Available Objective To explore the methods and curative effect of stereotactic surgery for treating writer's cramp (WC. Methods and Results Two patients with writer's cramp (tremor type underwent MRI guided stereotactic ventrointermediate (Vim thalamotomy on the left side. The symptoms of one patient disappeared immediately after operation, and the patient could write legibly. The tremor of right upper extremity in another patient was improved significantly. Two patients did not present obvious complications, and the previous symptoms were not found to recur during follow-up period respectively. Conclusions Stereotactic surgery for treatment of writer's cramp has definite therapeutic effect. MRI guided stereotactic technique can effectively avoid the complications of Vim thalamotomy. However, the indications of two methods in surgical treatment [thalamotomy and deep brain stimulation (DBS] and the respective merits still need further study. DOI: 10.3969/j.issn.1672-6731.2015.10.009

  3. A numerical study on dual-phase-lag model of bio-heat transfer during hyperthermia treatment.

    Science.gov (United States)

    Kumar, P; Kumar, Dinesh; Rai, K N

    2015-01-01

    The success of hyperthermia in the treatment of cancer depends on the precise prediction and control of temperature. It was absolutely a necessity for hyperthermia treatment planning to understand the temperature distribution within living biological tissues. In this paper, dual-phase-lag model of bio-heat transfer has been studied using Gaussian distribution source term under most generalized boundary condition during hyperthermia treatment. An approximate analytical solution of the present problem has been done by Finite element wavelet Galerkin method which uses Legendre wavelet as a basis function. Multi-resolution analysis of Legendre wavelet in the present case localizes small scale variations of solution and fast switching of functional bases. The whole analysis is presented in dimensionless form. The dual-phase-lag model of bio-heat transfer has compared with Pennes and Thermal wave model of bio-heat transfer and it has been found that large differences in the temperature at the hyperthermia position and time to achieve the hyperthermia temperature exist, when we increase the value of τT. Particular cases when surface subjected to boundary condition of 1st, 2nd and 3rd kind are discussed in detail. The use of dual-phase-lag model of bio-heat transfer and finite element wavelet Galerkin method as a solution method helps in precise prediction of temperature. Gaussian distribution source term helps in control of temperature during hyperthermia treatment. So, it makes this study more useful for clinical applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Experimental validation of hyperthermia SAR treatment planning using MR B1+ imaging

    International Nuclear Information System (INIS)

    Berg, Cornelis A T van den; Bartels, Lambertus W; Leeuw, Astrid A C De; Lagendijk, Jan J W; Kamer, Jeroen B Van de

    2004-01-01

    In this paper the concept of using B 1+ imaging as a means to validate SAR models for radiofrequency hyperthermia is presented. As in radiofrequency hyperthermia, in common clinical MR imaging which applies RF frequencies between 64 and 128 MHz, the RF field distribution inside a patient is largely determined by the dielectric distribution of the anatomy. Modern MR imaging techniques allow measurement of the RF magnetic field component B 1+ making it possible to measure at high resolution the dielectric interaction of the RF field with the patient. Given these considerations, we propose to use MR imaging to verify the validity of our dielectric patient model used for SAR models of radiofrequency hyperthermia. The aim of this study was to investigate the feasibility of this concept by performing B 1+ measurements and simulations on cylindrical split phantoms consisting of materials with dielectric properties similar to human tissue types. Important topics of investigation were the accuracy and sensitivity of B 1+ measurements and the validity of the electric model of the MR body coil. The measurements were performed on a clinical 1.5 T MR scanner with its quadrature body coil operating at 64 MHz. It was shown that even small B 1+ variations of 2 to 5% could be measured reliably in the phantom experiments. An electrical model of the transmit coil was implemented on our FDTD-based hyperthermia treatment planning platform and the RF field distributions were calculated assuming an idealized quadrature current distribution in the coil. A quantitatively good correlation between measurements and simulations was found for phantoms consisting of water and oil, while highly conductive phantoms show considerable deviations. However, assuming linear excitation for these conductive phantoms resulted in good correspondence. As an explanation it is suggested that the coil is being detuned due to the inductive nature of the conductive phantoms, breaking up the phase difference of

  5. Development of a Pneumatic Robot for MRI-guided Transperineal Prostate Biopsy and Brachytherapy: New Approaches

    OpenAIRE

    Song, Sang-Eun; Cho, Nathan B.; Fischer, Gregory; Hata, Nobuhito; Tempany, Clare; Fichtinger, Gabor; Iordachita, Iulian

    2010-01-01

    Magnetic Resonance Imaging (MRI) guided prostate biopsy and brachytherapy has been introduced in order to enhance the cancer detection and treatment. For the accurate needle positioning, a number of robotic assistants have been developed. However, problems exist due to the strong magnetic field and limited workspace. Pneumatically actuated robots have shown the minimum distraction in the environment but the confined workspace limits optimal robot design and thus controllability is often poor....

  6. Microwave hyperthermia as an adjuvant to radiation therapy. Summary experience of 256 multifraction treatment cases

    International Nuclear Information System (INIS)

    Bicher, H.I.

    1985-01-01

    Analysis is presented of a series of 256 human tumors treated under multifraction protocol regimes with standard controlled hyperthermia parameters and increasing doses of radiation therapy. Air cooled microwave applicators intracavitary and interstitial antennae operating at 915 or 300 MHz were used in various sites. Temperatures were measured by micro-thermocouples. Minimum tumor temperatures of 42 0 C were maintained at 1 hour, twice weekly. Treatment included a radiation dose of 1600-1700 rads. Tumor response was 94% with 60% or more total response. Frequency and duration of total responses depended mainly on the radiation dose. Skin tumors, melanomas, chest wall recurrences responded better than head and neck or intrapelvic recurrences. Side effects observed were minor burns; proctitis or oesophagitis with intracavitary devices; ulcerations or fistulae due to rapid tumor regression; 4 cases of pleuritis treating chest wall. Overall toxicity was less than 5%. In conclusion: 1) Combination heat-low dose radiation offers good palliation. 2) Response depends on radiation dose. 3) Combination of full dose radiation therapy plus hyperthermia proves to be well tolerated

  7. MRI-guided biopsies and minimally invasive therapy for prostate cancer

    Directory of Open Access Journals (Sweden)

    Sangeet Ghai

    2015-01-01

    Full Text Available Recent advances in multiparametric magnetic resonance imaging (mp-MRI have led to a paradigm shift in the diagnosis and management of prostate cancer (PCa. Its sensitivity in detecting clinically significant cancer and the ability to localize the tumor within the prostate gland has opened up discussion on targeted diagnosis and therapy in PCa. Use of mp-MRI in conjunction with prostate-specific antigen followed by targeted biopsy allows for a better diagnostic pathway than transrectal ultrasound (TRUS biopsy and improves the diagnosis of PCa. Improved detection of PCa by mp-MRI has also opened up opportunities for focal therapy within the organ while reducing the incidence of side-effects associated with the radical treatment methods for PCa. This review discusses the evidence and techniques for in-bore MRI-guided prostate biopsy and provides an update on the status of MRI-guided targeted focal therapy in PCa.

  8. MRI-guided laser-induced thermotherapy (LITT) of liver metastases: clinical evaluation

    International Nuclear Information System (INIS)

    Vogl, T.J.; Weinhold, N.; Mueller, P.; Mack, M.; Scholz, W.; Philipp, C.; Roggan, A.; Felix, R.

    1996-01-01

    The goal was to perform an evaluation of MRI-guided laser-induced thermotherapy (LITT) of liver metastases as a clinical method. In a prospective study, 50 patients with liver metastases of colorectal carcinoma (35 patients), or other primary tumors (15 patients) were treated with LITT. For preparation and intermittent controls of therapy, standardized MRI examinations were made. Online monitoring during the the LITT was done with temperature-sensitive T1-weighted sequences (FLASH-2D, TurboFLASH). All in all, 83 metastases of a volume between 1 and 282 cubic centimeters (median = ± 10 cm 3 ) were treated.During performance of the LITT, a decrease of signal intensity in the thermosensitive sequences was measured for the application area, and was correlated with fluorine-optical temperature measurements. The MRI-guided LITT is a novel, potential modality for treatment of liver metastases, and poses only minimal clinical risks. (orig./VHE) [de

  9. Development of a Pneumatic Robot for MRI-guided Transperineal Prostate Biopsy and Brachytherapy: New Approaches

    Science.gov (United States)

    Song, Sang-Eun; Cho, Nathan B.; Fischer, Gregory; Hata, Nobuhito; Tempany, Clare; Fichtinger, Gabor; Iordachita, Iulian

    2011-01-01

    Magnetic Resonance Imaging (MRI) guided prostate biopsy and brachytherapy has been introduced in order to enhance the cancer detection and treatment. For the accurate needle positioning, a number of robotic assistants have been developed. However, problems exist due to the strong magnetic field and limited workspace. Pneumatically actuated robots have shown the minimum distraction in the environment but the confined workspace limits optimal robot design and thus controllability is often poor. To overcome the problem, a simple external damping mechanism using timing belts was sought and a 1-DOF mechanism test result indicated sufficient positioning accuracy. Based on the damping mechanism and modular system design approach, a new workspace-optimized 4-DOF parallel robot was developed for the MRI-guided prostate biopsy and brachytherapy. A preliminary evaluation of the robot was conducted using previously developed pneumatic controller and satisfying results were obtained. PMID:21399734

  10. Hyperthermia quality assurance

    International Nuclear Information System (INIS)

    Shrivastava, P.N.; Paliwal, B.R.

    1984-01-01

    Hyperthermia Physics Center (HPC) operating under contract with the National Cancer Institute is developing a Quality Assurance program for local and regional hyperthermia. The major clinical problem in hyperthermia treatments is that they are extremely difficult to plan, execute, monitor and reproduce. A scientific basis for treatment planning can be established only after ensuring that the performance of heat generating and temperature monitoring systems are reliable. The HPC is presently concentrating on providing uniform NBS traceable calibration of thermometers and evaluation of reproducibility for power generator operation, applicator performance, phanta compositions, system calibrations and personnel shielding. The organizational plan together with recommended evaluation measurements, procedures and criteria are presented

  11. Magnetic fluid hyperthermia (MFH) as an alternative option in the treatment of recurrent malignant gliomas

    International Nuclear Information System (INIS)

    Maier-Hauff, K.; Jordan, A.; Nestler, D.; Scholz, R.; Feussner, A.; Gneveckow, U.; Wust, P.; Felix, R.

    2005-01-01

    Full text: The prognosis of glioblastoma (GB) remains poor despite the better neuro-imaging modalities and neurosurgical techniques. The survival of patients (PTS) depends on local tumor control, which is not guaranteed by the actual standard therapy. Magnetic fluid hyperthermia (MFH) in combination with external irradiation (RT) is a worldwide new method, which heats up selectively tumor tissue coupling a magnetic field to the applicated magnetic fluid (MF). In a phase I study with 16 PTS the applicability and tolerance of MFH combined with RT was evaluated. We present our preliminary results in 16 PTS. Depending on the tumor volume we implanted navigated 1-4 ml MF in the tumor area. The MF consists of iron oxide nanoparticles coated with a MG-specific shell dispersed in water. When the particles are exposed to an externally applied AC magnetic field, intratumoral steady-state temperatures of 43-50 o C or even higher for thermo ablation, were achieved during 60 minutes. The target temperature was measures continuously on-line by a 0.5 mm fibre optic invasive thermometry and controlled by the field strength of the AC magnetic field applicator. Four days after surgery irradiation was applied with 2 Gy / fraction 5 times a week plus 2 sessions of hyperthermia per week over 3 weeks. Because tumor power absorption was highly reproducible in each session, only the first six MFH treatments required thermometry. Further MFH applications were completely non-invasive. In 16 PTS 98 MFH therapies were done without side effects. In-vivo measured temperatures of 46 - 50 o C were highly reproducible in the target volume. In 16 cases MFH has been completed. During actual 15 months follow-up, 10 PTS showed no tumor progress where as in five PTS the tumor volume increased. Five PTS died of non tumor related complications and two PTS of tumor progress. The magnetic fluid hyperthermia in combination with radiation is a useful method for an intensified local treatment of recurrent

  12. An automated method for mapping human tissue permittivities by MRI in hyperthermia treatment planning

    International Nuclear Information System (INIS)

    Farace, Paolo; Antolini, Renzo; Pontalti, Rolando; Cristoforetti, Luca; Scarpa, Marina

    1997-01-01

    This paper presents an automatic method to obtain tissue complex permittivity values to be used as input data in the computer modelling for hyperthermia treatment planning. Magnetic resonance (MR) images were acquired and the tissue water content was calculated from the signal intensity of the image pixels. The tissue water content was converted into complex permittivity values by monotonic functions based on mixture theory. To obtain a water content map by MR imaging a gradient-echo pulse sequence was used and an experimental procedure was set up to correct for relaxation and radiofrequency field inhomogeneity effects on signal intensity. Two approaches were followed to assign the permittivity values to fat-rich tissues: (i) fat-rich tissue localization by a segmentation procedure followed by assignment of tabulated permittivity values; (ii) water content evaluation by chemical shift imaging followed by permittivity calculation. Tests were performed on phantoms of known water content to establish the reliability of the proposed method. MRI data were acquired and processed pixel-by-pixel according to the outlined procedure. The signal intensity in the phantom images correlated well with water content. Experiments were performed on volunteers' healthy tissue. In particular two anatomical structures were chosen to calculate permittivity maps: the head and the thigh. The water content and electric permittivity values were obtained from the MRI data and compared to others in the literature. A good agreement was found for muscle, cerebrospinal fluid (CSF) and white and grey matter. The advantages of the reported method are discussed in the light of possible application in hyperthermia treatment planning. (author)

  13. An automated method for mapping human tissue permittivities by MRI in hyperthermia treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Farace, Paolo; Antolini, Renzo [CMBM-ITC, Centro Materiali e Biofisica Medica, 38050 Povo-Trento (Italy); Dipartimento di Fisica and INFM, Universita di Trento, 38050 Povo-Trento (Italy); Pontalti, Rolando; Cristoforetti, Luca [CMBM-ITC, Centro Materiali e Biofisica Medica, 38050 Povo-Trento (Italy); Scarpa, Marina [Dipartimento di Fisica and INFM, Universita di Trento, 38050 Povo-Trento (Italy)

    1997-11-01

    This paper presents an automatic method to obtain tissue complex permittivity values to be used as input data in the computer modelling for hyperthermia treatment planning. Magnetic resonance (MR) images were acquired and the tissue water content was calculated from the signal intensity of the image pixels. The tissue water content was converted into complex permittivity values by monotonic functions based on mixture theory. To obtain a water content map by MR imaging a gradient-echo pulse sequence was used and an experimental procedure was set up to correct for relaxation and radiofrequency field inhomogeneity effects on signal intensity. Two approaches were followed to assign the permittivity values to fat-rich tissues: (i) fat-rich tissue localization by a segmentation procedure followed by assignment of tabulated permittivity values; (ii) water content evaluation by chemical shift imaging followed by permittivity calculation. Tests were performed on phantoms of known water content to establish the reliability of the proposed method. MRI data were acquired and processed pixel-by-pixel according to the outlined procedure. The signal intensity in the phantom images correlated well with water content. Experiments were performed on volunteers' healthy tissue. In particular two anatomical structures were chosen to calculate permittivity maps: the head and the thigh. The water content and electric permittivity values were obtained from the MRI data and compared to others in the literature. A good agreement was found for muscle, cerebrospinal fluid (CSF) and white and grey matter. The advantages of the reported method are discussed in the light of possible application in hyperthermia treatment planning. (author)

  14. An automated method for mapping human tissue permittivities by MRI in hyperthermia treatment planning.

    Science.gov (United States)

    Farace, P; Pontalti, R; Cristoforetti, L; Antolini, R; Scarpa, M

    1997-11-01

    This paper presents an automatic method to obtain tissue complex permittivity values to be used as input data in the computer modelling for hyperthermia treatment planning. Magnetic resonance (MR) images were acquired and the tissue water content was calculated from the signal intensity of the image pixels. The tissue water content was converted into complex permittivity values by monotonic functions based on mixture theory. To obtain a water content map by MR imaging a gradient-echo pulse sequence was used and an experimental procedure was set up to correct for relaxation and radiofrequency field inhomogeneity effects on signal intensity. Two approaches were followed to assign the permittivity values to fat-rich tissues: (i) fat-rich tissue localization by a segmentation procedure followed by assignment of tabulated permittivity values; (ii) water content evaluation by chemical shift imaging followed by permittivity calculation. Tests were performed on phantoms of known water content to establish the reliability of the proposed method. MRI data were acquired and processed pixel-by-pixel according to the outlined procedure. The signal intensity in the phantom images correlated well with water content. Experiments were performed on volunteers' healthy tissue. In particular two anatomical structures were chosen to calculate permittivity maps: the head and the thigh. The water content and electric permittivity values were obtained from the MRI data and compared to others in the literature. A good agreement was found for muscle, cerebrospinal fluid (CSF) and white and grey matter. The advantages of the reported method are discussed in the light of possible application in hyperthermia treatment planning.

  15. An automated method for mapping human tissue permittivities by MRI in hyperthermia treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Farace, Paolo; Antolini, Renzo [CMBM-ITC, Centro Materiali e Biofisica Medica, 38050 Povo-Trento (Italy); Dipartimento di Fisica and INFM, Universita di Trento, 38050 Povo-Trento (Italy); Pontalti, Rolando; Cristoforetti, Luca [CMBM-ITC, Centro Materiali e Biofisica Medica, 38050 Povo-Trento (Italy); Scarpa, Marina [Dipartimento di Fisica and INFM, Universita di Trento, 38050 Povo-Trento (Italy)

    1997-11-01

    This paper presents an automatic method to obtain tissue complex permittivity values to be used as input data in the computer modelling for hyperthermia treatment planning. Magnetic resonance (MR) images were acquired and the tissue water content was calculated from the signal intensity of the image pixels. The tissue water content was converted into complex permittivity values by monotonic functions based on mixture theory. To obtain a water content map by MR imaging a gradient-echo pulse sequence was used and an experimental procedure was set up to correct for relaxation and radiofrequency field inhomogeneity effects on signal intensity. Two approaches were followed to assign the permittivity values to fat-rich tissues: (i) fat-rich tissue localization by a segmentation procedure followed by assignment of tabulated permittivity values; (ii) water content evaluation by chemical shift imaging followed by permittivity calculation. Tests were performed on phantoms of known water content to establish the reliability of the proposed method. MRI data were acquired and processed pixel-by-pixel according to the outlined procedure. The signal intensity in the phantom images correlated well with water content. Experiments were performed on volunteers' healthy tissue. In particular two anatomical structures were chosen to calculate permittivity maps: the head and the thigh. The water content and electric permittivity values were obtained from the MRI data and compared to others in the literature. A good agreement was found for muscle, cerebrospinal fluid (CSF) and white and grey matter. The advantages of the reported method are discussed in the light of possible application in hyperthermia treatment planning. (author)

  16. Novel hyperthermia applicator system allows adaptive treatment planning: Preliminary clinical results in tumour-bearing animals.

    Science.gov (United States)

    Dressel, S; Gosselin, M-C; Capstick, M H; Carrasco, E; Weyland, M S; Scheidegger, S; Neufeld, E; Kuster, N; Bodis, S; Rohrer Bley, C

    2017-09-11

    Hyperthermia (HT) as an adjuvant to radiation therapy (RT) is a multimodality treatment method to enhance therapeutic efficacy in different tumours. High demands are placed on the hardware and treatment planning software to guarantee adequately planned and applied HT treatments. The aim of this prospective study was to determine the effectiveness and safety of the novel HT system in tumour-bearing dogs and cats in terms of local response and toxicity as well as to compare planned with actual achieved data during heating. A novel applicator with a flexible number of elements and integrated closed-loop temperature feedback control system, and a tool for patient-specific treatment planning were used in a combined thermoradiotherapy protocol. Good agreement between predictions from planning and clinical outcome was found in 7 of 8 cases. Effective HT treatments were planned and verified with the novel system and provided improved quality of life in all but 1 patient. This individualized treatment planning and controlled heat exposure allows adaptive, flexible and safe HT treatments in palliatively treated animal patients. © 2017 John Wiley & Sons Ltd.

  17. 500 kHZ intracavitary hyperthermia in the treatment of patients with cervical and endometrial cancer - preliminary results and treatment description

    International Nuclear Information System (INIS)

    Piotrowicz, N.; Lyczek, J.; Zielinski, J.; Debicki, P.

    2002-01-01

    The effectiveness of elevated temperature (hyperthermia) in cancer treatment is a well-known issue. However, due to technical problems with generating hyperthermia within the tumour and, at the same time, sparing the healthy tissues, in practice this modality is not widely used. Local hyperthermia was induced by a computer-controlled generator (500 kHz) with three amplifiers transmitting energy to the lesion via a modified uterine brachytherapy applicator. Temperature was measured with 3 thermocouples.Total treatment time was 60-90 minutes. 10 patients with cervical and endometrial cancer were enrolled into this study and 11 procedures were performed. Prior to hyperthermia all patients were treated with external field irradiation to the pelvis to the dose of 45-46 Gy. Intracavitary LDR/HDR brachytherapy (dose of 45 Gy/point Ai n two fractions) with colpostat used for the hyperthermia procedure was than performed. In all cases, except one, caused by equipment failure, biologically stable temperature was observed. No severe side effects of treatment were observed. There was no need to terminate treatment due to high temperature intolerance. (author)

  18. WE-EF-BRD-01: Past, Present and Future: MRI-Guided Radiotherapy From 2005 to 2025

    Energy Technology Data Exchange (ETDEWEB)

    Lagendijk, J. [University Medical Center Utrecht (Netherlands)

    2015-06-15

    MRI-guided treatment is a growing area of medicine, particularly in radiotherapy and surgery. The exquisite soft tissue anatomic contrast offered by MRI, along with functional imaging, makes the use of MRI during therapeutic procedures very attractive. Challenging the utility of MRI in the therapy room are many issues including the physics of MRI and the impact on the environment and therapeutic instruments, the impact of the room and instruments on the MRI; safety, space, design and cost. In this session, the applications and challenges of MRI-guided treatment will be described. The session format is: Past, present and future: MRI-guided radiotherapy from 2005 to 2025: Jan Lagendijk Battling Maxwell’s equations: Physics challenges and solutions for hybrid MRI systems: Paul Keall I want it now!: Advances in MRI acquisition, reconstruction and the use of priors to enable fast anatomic and physiologic imaging to inform guidance and adaptation decisions: Yanle Hu MR in the OR: The growth and applications of MRI for interventional radiology and surgery: Rebecca Fahrig Learning Objectives: To understand the history and trajectory of MRI-guided radiotherapy To understand the challenges of integrating MR imaging systems with linear accelerators To understand the latest in fast MRI methods to enable the visualisation of anatomy and physiology on radiotherapy treatment timescales To understand the growing role and challenges of MRI for image-guided surgical procedures My disclosures are publicly available and updated at: http://sydney.edu.au/medicine/radiation-physics/about-us/disclosures.php.

  19. Combined treatment of 8 MHz radiofrequency hyperthermia and irradiation for advanced urological malignancies

    International Nuclear Information System (INIS)

    Nakajima, Kazuyoshi; Hisazumi, Haruo; Yamamoto, Hajime; Naito, Katsusuke; Misaki, Toshimitsu; Kobashi, Kazunori; Yokoyama, Osamu; Saito, Yasuo

    1986-01-01

    A combined therapy of irradiation and 8 MHz radiofrequency hyperthermia using Thermotron-RF Model 8 was carried out in a total of 26 patients with urological malignancies; 9 renal cancers, 1 renal capsular tumor, multiple liver metastatic lesions of renal cancer, a postoperative mediastinal metastasis of renal cancer, 2 ureteral cancers associated with bladder cancers, 4 bladder cancers, 4 prostatic cancers, a postoperative local recurrent tumor of an adult type Wilms' tumor, and multiple skin metastatic lesions of a penile cancer. Previous therapies were unsuccessful, or surgical interventions were not indicated because of poor general conditions. They were irradiated with daily 1.8 to 2.0 Gy, 5 times a week, or daily 2.0 to 4.0 Gy twice a week. Hyperthermia was induced twice a week within one hour after each irradiation, in total 10 times for 5 weeks. Intratumoral temperature was kept between 42.0 to 44.0 deg C. Clinical efficacy was evaluated by CT, ultrasound and biochemical data. Partial tumor regression, defined as the regression of 50 % or more, was obtained in one of the 9 renal cancers, in the mediastinal metastasis of renal cancer, 2 of the 4 prostatic cancers, one of the 4 bladder cancers and the 2 ureteral cancers, CR was obtained in the 2 associated bladder cancers. As side effects, a mild skin burns and anorexia were observed in approximately 50 % of the cases. Subcutaneous fat tissue indurations occurred in 6 of the 30 patients, who had 15 mm or more thickness of subdermal fat tissues, after treatment. (author)

  20. Association of rectal toxicity with thermal dose parameters in treatment of locally advanced prostate cancer with radiation and hyperthermia

    International Nuclear Information System (INIS)

    Hurwitz, Mark D.; Kaplan, Irving D.; Hansen, Jorgen L.; Prokopios-Davos, Savina; Topulos, George P.; Wishnow, Kenneth; Manola, Judith; Bornstein, Bruce A.; Hynynen, Kullervo

    2002-01-01

    Purpose: Although hyperthermia has been used for more than two decades in the treatment of pelvic tumors, little is known about the potential impact of heat on rectal toxicity when combined with other treatment modalities. Because rectal toxicity is a concern with radiation and may be exacerbated by hyperthermia, definition of the association of thermal dose parameters with rectal toxicity is important. In this report, we correlate rectal toxicity with thermal dose parameters for patients treated with hyperthermia and radiation for prostate cancer. Methods and Materials: Thirty patients with T2b-T3b disease (1992 American Joint Committee On Cancer criteria) enrolled in a Phase II study of external beam radiation ± androgen-suppressive therapy with two transrectal ultrasound hyperthermia treatments were assessed for rectal toxicity. Prostatic and anterior rectal wall temperatures were monitored for all treatments. Rectal wall temperatures were limited to 40 deg. C in 19 patients, 41 deg. C in 3 patients, and 42 deg. C in 8 patients. Logistic regression was used to estimate the log hazard of developing National Cancer Institute Common Toxicity Criteria Grade 2 toxicity based on temperature parameters. The following were calculated: hazard ratios, 95% confidence intervals, p values for statistical significance of each parameter, and proportion of variability explained for each parameter. Results: Gastrointestinal toxicity was limited to Grade 2. The rate of acute Grade 2 proctitis was greater for patients with an allowable rectal wall temperature of >40 deg. C. In this group, 7 of 11 patients experienced acute Grade 2 proctitis, as opposed to 3 of 19 patients in the group with rectal wall temperatures limited to 40 deg. C (p=0.004). Preliminary assessment of long-term toxicity revealed no differences in toxicity. Hazard ratios for acute Grade 2 proctitis for allowable rectal wall temperature, average rectal wall Tmax, and average prostate Tmax were 9.33 (p=0.01), 3

  1. MRI guided needle localization in a patient with recurrence pleomorphic sarcoma and post-operative scarring

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Ching-Di [Chang Gung University College of Medicine, Department of Radiology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung (China); Harvard Medical School, Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA (United States); Wei, Jesse; Wu, Jim S. [Harvard Medical School, Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA (United States); Goldsmith, Jeffrey D. [Harvard Medical School, Department of Pathology, Beth Israel Deaconess Medical Center, Boston, MA (United States); Gebhardt, Mark C. [Harvard Medical School, Department of Orthopedic Surgery, Beth Israel Deaconess Medical Center, Boston, MA (United States)

    2017-07-15

    MRI-guided wire localization is commonly used for surgical localization of breast lesions. Here we introduce an alternative use of this technique to help with surgical resection of a recurrent pleomorphic sarcoma embedded in extensive post-treatment scar tissue. We describe a case of recurrent pleomorphic soft tissue sarcoma in the thigh after treatment with neoadjuvant therapy, surgery, and radiation. Due to the distortion of the normal tissue architecture and formation of extensive scar tissue from prior treatment, wire localization under MRI was successfully used to assist the surgeon in identifying the recurrent tumor for removal. (orig.)

  2. Study on the usefulness of high-frequency analysis of the combined treatment of cancer with hyperthermia

    International Nuclear Information System (INIS)

    Ji, Youn Sang; Dong, Kyung Rae; Yeo, Hwa Yeon

    2016-01-01

    In order to understand the usefulness to the high-frequency thermal therapy of cancer staging according to the TNM classification treatment, was to evaluate the effect of high frequency hyperthermia treatment approach through other means and whether other organs, according to the combined presence of transition. Targeted to receive more than a total of 1 cycle high frequency heat treatment at C hospital that performed the high-frequency hyperthermia cancer patients 92 people out stage, depending on the presence or absence of metastasis, combined hyperthermia patients for statistics before and after treatment the therapeutic effect of the therapeutic classification. Out of a total of 92 patients decrease 11 patients, stable 71 patients, with increase 10 patients, the rate of increase is the result of about 11% patients showed a decrease of about 89% is occupied by patients and a stable rate. There is strong evidence for the usefulness as a secondary therapy to maintain the quality of life, while slowing the progression of cancer by a high-frequency heat treatment

  3. Study on the usefulness of high-frequency analysis of the combined treatment of cancer with hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Youn Sang; Dong, Kyung Rae [Dept. of Radiological Technology, Gwangju Health University, Gwangju (Korea, Republic of); Yeo, Hwa Yeon [Dept. of of Radiology, Nambu University, Gwangju (Korea, Republic of)

    2016-11-15

    In order to understand the usefulness to the high-frequency thermal therapy of cancer staging according to the TNM classification treatment, was to evaluate the effect of high frequency hyperthermia treatment approach through other means and whether other organs, according to the combined presence of transition. Targeted to receive more than a total of 1 cycle high frequency heat treatment at C hospital that performed the high-frequency hyperthermia cancer patients 92 people out stage, depending on the presence or absence of metastasis, combined hyperthermia patients for statistics before and after treatment the therapeutic effect of the therapeutic classification. Out of a total of 92 patients decrease 11 patients, stable 71 patients, with increase 10 patients, the rate of increase is the result of about 11% patients showed a decrease of about 89% is occupied by patients and a stable rate. There is strong evidence for the usefulness as a secondary therapy to maintain the quality of life, while slowing the progression of cancer by a high-frequency heat treatment.

  4. Robotic System for MRI-Guided Stereotactic Neurosurgery

    Science.gov (United States)

    Li, Gang; Cole, Gregory A.; Shang, Weijian; Harrington, Kevin; Camilo, Alex; Pilitsis, Julie G.; Fischer, Gregory S.

    2015-01-01

    Stereotaxy is a neurosurgical technique that can take several hours to reach a specific target, typically utilizing a mechanical frame and guided by preoperative imaging. An error in any one of the numerous steps or deviations of the target anatomy from the preoperative plan such as brain shift (up to 20 mm), may affect the targeting accuracy and thus the treatment effectiveness. Moreover, because the procedure is typically performed through a small burr hole opening in the skull that prevents tissue visualization, the intervention is basically “blind” for the operator with limited means of intraoperative confirmation that may result in reduced accuracy and safety. The presented system is intended to address the clinical needs for enhanced efficiency, accuracy, and safety of image-guided stereotactic neurosurgery for Deep Brain Stimulation (DBS) lead placement. The work describes a magnetic resonance imaging (MRI)-guided, robotically actuated stereotactic neural intervention system for deep brain stimulation procedure, which offers the potential of reducing procedure duration while improving targeting accuracy and enhancing safety. This is achieved through simultaneous robotic manipulation of the instrument and interactively updated in situ MRI guidance that enables visualization of the anatomy and interventional instrument. During simultaneous actuation and imaging, the system has demonstrated less than 15% signal-to-noise ratio (SNR) variation and less than 0.20% geometric distortion artifact without affecting the imaging usability to visualize and guide the procedure. Optical tracking and MRI phantom experiments streamline the clinical workflow of the prototype system, corroborating targeting accuracy with 3-axis root mean square error 1.38 ± 0.45 mm in tip position and 2.03 ± 0.58° in insertion angle. PMID:25376035

  5. In vitro application of Fe/MgO nanoparticles as magnetically mediated hyperthermia agents for cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    Chalkidou, A. [Department of Physics, Aristotle University of Thessaloniki, 54 124 Thessaloniki (Greece); Molecular Oncology Laboratory, Theagenio Cancer Hospital, Alexandrou Simeonidi Street 2, 54 007 Thessaloniki (Greece); Simeonidis, K. [Department of Physics, Aristotle University of Thessaloniki, 54 124 Thessaloniki (Greece); Angelakeris, M., E-mail: agelaker@auth.g [Department of Physics, Aristotle University of Thessaloniki, 54 124 Thessaloniki (Greece); Samaras, T. [Department of Physics, Aristotle University of Thessaloniki, 54 124 Thessaloniki (Greece); Martinez-Boubeta, C. [Departament d' Electronica, Universitat de Barcelona, Marti i Franques 1, Barcelona 08028 (Spain); Balcells, Ll. [ICMAB-CSIC, Campus UAB, Bellaterra 08193 (Spain); Papazisis, K. [Molecular Oncology Laboratory, Theagenio Cancer Hospital, Alexandrou Simeonidi Street 2, 54 007 Thessaloniki (Greece); Dendrinou-Samara, C. [Department of Chemistry, Aristotle University of Thessaloniki, 54 124 Thessaloniki (Greece); Kalogirou, O. [Department of Physics, Aristotle University of Thessaloniki, 54 124 Thessaloniki (Greece)

    2011-03-15

    In this work we study the heating efficiency of Fe/MgO magnetic core/biocompatible shell nanoparticles and their in vitro application in magnetic hyperthermia on cancer cells. Different human breast cancer cell lines were used to assess the suitability of nanoparticles for in vivo application. The experiments revealed a very good cytotoxicity profile and significant uptake efficiency together with relatively high specific absorption rates and fast thermal response, features that are crucial for adequate thermal efficiency and minimum duration of treatment. - Research highlights: > Fe/MgO magnetic core/shell nanoparticles and their in vitro application for magnetic hyperthermia. > Very good cytotoxicity profile and significant uptake efficiency in three human breast cancer cell lines. > SAR values and fast thermal response guarantee adequate thermal efficiency and minimum treatment duration.

  6. A support system in virtual reality for effective hyperthermia treatments. Heating properties of needle applicator for brain tumors

    International Nuclear Information System (INIS)

    Shindo, Yasuhiro; Iseki, Yuya; Nakane, Kazuya; Mimoto, Naoki; Kubo, Mitsunori; Kato, Kazuo; Takahashi, Hideaki; Uzuka, Takeo; Fujii, Yukihiko

    2011-01-01

    This paper describes the effectiveness of the developed simulator system for performing an effective hyperthermia treatment with a needle applicator in virtual reality (VR). The human brain is protected by the skull, which makes it difficult to non-invasively heat deep brain tumors with electromagnetic energy. Generally, needle applicators were used in clinical practice to heat brain tumors. However, some problems exist. One is that this heating method has a small heating area around the needle. In order to expand the heating area of a needle applicator, we developed a new type of needle applicator made from a shape memory alloy (SMA). The thermal properties of the SMA were checked experimentally using the developed heating system. As a result, the proposed needle applicator made of SMA is useful to create a wider heating area inside a tumor. Another problem is that medical doctors find it difficult to put a needle applicator into a target point inside of tumors. Therefore, a support system for performing an effective hyperthermia treatment is required in the clinic. In this paper, first, we constructed an anatomical 3-D model from magnetic resonance imaging (MRI) and X-ray computed tomography (CT) images by using 3-D computer aided design (CAD) software. Second, we presented the finite element method (FEM) model which is divided into non-linear elements on 3-D computer graphics (CG). Finally, we calculated temperature distributions using the 3-D FEM model with blood perfusion during hyperthermia treatments. From these results, it was found that the proposed VR system is effective for performing hyperthermia treatments. (author)

  7. Hyperthermia treatment of tumors by mesenchymal stem cell-delivered superparamagnetic iron oxide nanoparticles

    Directory of Open Access Journals (Sweden)

    Kalber TL

    2016-05-01

    Full Text Available Tammy L Kalber,1,2,* Katherine L Ordidge,1,2,* Paul Southern,3 Michael R Loebinger,1 Panagiotis G Kyrtatos,2,3 Quentin A Pankhurst,3,* Mark F Lythgoe,2,* Sam M Janes1,* 1Lungs for Living Research Centre, UCL Respiratory, University College London, 2UCL Centre for Advanced Biomedical Imaging, Division of Medicine, University College London, 3Healthcare Biomagnetics Laboratory, University College London, London, UK *These authors contributed equally to this work Abstract: Magnetic hyperthermia – a potential cancer treatment in which superparamagnetic iron oxide nanoparticles (SPIONs are made to resonantly respond to an alternating magnetic field (AMF and thereby produce heat – is of significant current interest. We have previously shown that mesenchymal stem cells (MSCs can be labeled with SPIONs with no effect on cell proliferation or survival and that within an hour of systemic administration, they migrate to and integrate into tumors in vivo. Here, we report on some longer term (up to 3 weeks post-integration characteristics of magnetically labeled human MSCs in an immunocompromized mouse model. We initially assessed how the size and coating of SPIONs dictated the loading capacity and cellular heating of MSCs. Ferucarbotran® was the best of those tested, having the best like-for-like heating capability and being the only one to retain that capability after cell internalization. A mouse model was created by subcutaneous flank injection of a combination of 0.5 million Ferucarbotran-loaded MSCs and 1.0 million OVCAR-3 ovarian tumor cells. After 2 weeks, the tumors reached ~100 µL in volume and then entered a rapid growth phase over the third week to reach ~300 µL. In the control mice that received no AMF treatment, magnetic resonance imaging (MRI data showed that the labeled MSCs were both incorporated into and retained within the tumors over the entire 3-week period. In the AMF-treated mice, heat increases of ~4°C were observed

  8. SU-F-J-05: The Effect of Air Pockets in the Urinary Bladder During Bladder Hyperthermia Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Schooneveldt, G.; Kok, H.P.; Bakker, A.; Geijsen, E.D.; Reijke, T.M. de; Crezee, J. [Academisch Medisch Centrum / Universiteit van Amsterdam, Amsterdam (Netherlands)

    2016-06-15

    Purpose: Hyperthermia combined with Mitomycin C is used for the treatment of non-muscle invasive bladder cancer (NMIBC), using a phased array system of microwave antennas for bladder heating. Often some air is present in the bladder, which effectively blocks the microwave radiation, potentially preventing proper treatment of that part of the bladder. Air can be a relevant fraction of the bladder content and large air pockets are expected to have a noticeable influence on achieved temperatures. Methods: We analysed 14 NMIBC patients treated at our institute with our AMC-4 hyperthermia device with four 70MHz antennas around the pelvis. A CT scan was made after treatment and a physician delineated the bladder on the CT scan. On the same scan, the amount of air present in the bladder was delineated. Using our in-house developed hyperthermia treatment planning system, we simulated the treatment using the clinically applied device settings. We did this once with the air pocket delineated on the CT scan, and once with the same volume filled with bladder tissue. Results: The patients had on average 4.2ml (range 0.8–10.1ml) air in the bladder. The bladder volume was delineated by the physician, that is including air pocket and bladder wall, was on average 253ml (range 93–452ml). The average volume in which changes exceeded 0.25°C was 22ml (range 0–108 ml), with the bladder being up to 2°C cooler when an air pocket was present. Except for extreme cases, there was no evident relation between the quantity of air and the difference in temperature. Conclusion: The effect of an air pocket in the bladder during bladder hyperthermia treatment varies strongly between patients. Generally, this leads to lower temperatures in the bladder, potentially affecting treatment quality, and suggesting that care need be taken to minimise the size of air pockets during hyperthermia treatments. The KWF Dutch Cancer Society financially supported this work, grant UVA 2012-5539.

  9. The application of early post-operative combination therapy with interstitial hyperthermia in the treatment of malignant gliomas

    International Nuclear Information System (INIS)

    Stahl, H.; Wust, P.; Maier-Hauff, K.; Seebass, M.; Mischel, M.; Grammler, M.; Golde, G.; Loeffel, J.; Felix, R.

    1995-01-01

    A pilot study was performed to examine practicality, tolerability, effectiveness and scope for improvement in early postoperative hyperthermia treatment following catheter implantation as part of (partial) tumor resection. Each CT data set was transferred into a VAX 3100 workstation for retrospective analysis of the hyperthermia treatment. The implanted catheters were segmented and the distributions of power density and temperature were simulated. We sought to achieve the best possible temperature distributions by optimising the catheter arrangement in the planning calculations. The corresponding Ir-192-source brachytherapy treatments were simulated in a similar way using the implanted, as well as optimised catheter arrays. Intraoperative catheter implantation in 4 patients was problem-free. Postoperative complications were not observed, neither were infections. Interstitial microwave hyperthermia in combination with percutaneous irradiation or chemotherapy a few days after the operation was also tolerated well by all patients. Effective temperatures (of at least 42 C) were regularly achieved at measurement points, but the temperature distributions were unsatisfactory, with T 90 values (the temperature reached in at least 90% of the target volume) of under 38 C. Measured temperature/position curves showed qualitative correlation with the simulated calculations. The catheter positions determined by optimisation varied significantly from the positions clinically used. (orig./MG) [de

  10. CT-based patient modeling for head and neck hyperthermia treatment planning: manual versus automatic normal-tissue-segmentation.

    Science.gov (United States)

    Verhaart, René F; Fortunati, Valerio; Verduijn, Gerda M; van Walsum, Theo; Veenland, Jifke F; Paulides, Margarethus M

    2014-04-01

    Clinical trials have shown that hyperthermia, as adjuvant to radiotherapy and/or chemotherapy, improves treatment of patients with locally advanced or recurrent head and neck (H&N) carcinoma. Hyperthermia treatment planning (HTP) guided H&N hyperthermia is being investigated, which requires patient specific 3D patient models derived from Computed Tomography (CT)-images. To decide whether a recently developed automatic-segmentation algorithm can be introduced in the clinic, we compared the impact of manual- and automatic normal-tissue-segmentation variations on HTP quality. CT images of seven patients were segmented automatically and manually by four observers, to study inter-observer and intra-observer geometrical variation. To determine the impact of this variation on HTP quality, HTP was performed using the automatic and manual segmentation of each observer, for each patient. This impact was compared to other sources of patient model uncertainties, i.e. varying gridsizes and dielectric tissue properties. Despite geometrical variations, manual and automatic generated 3D patient models resulted in an equal, i.e. 1%, variation in HTP quality. This variation was minor with respect to the total of other sources of patient model uncertainties, i.e. 11.7%. Automatically generated 3D patient models can be introduced in the clinic for H&N HTP. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. CT-based patient modeling for head and neck hyperthermia treatment planning: Manual versus automatic normal-tissue-segmentation

    International Nuclear Information System (INIS)

    Verhaart, René F.; Fortunati, Valerio; Verduijn, Gerda M.; Walsum, Theo van; Veenland, Jifke F.; Paulides, Margarethus M.

    2014-01-01

    Background and purpose: Clinical trials have shown that hyperthermia, as adjuvant to radiotherapy and/or chemotherapy, improves treatment of patients with locally advanced or recurrent head and neck (H and N) carcinoma. Hyperthermia treatment planning (HTP) guided H and N hyperthermia is being investigated, which requires patient specific 3D patient models derived from Computed Tomography (CT)-images. To decide whether a recently developed automatic-segmentation algorithm can be introduced in the clinic, we compared the impact of manual- and automatic normal-tissue-segmentation variations on HTP quality. Material and methods: CT images of seven patients were segmented automatically and manually by four observers, to study inter-observer and intra-observer geometrical variation. To determine the impact of this variation on HTP quality, HTP was performed using the automatic and manual segmentation of each observer, for each patient. This impact was compared to other sources of patient model uncertainties, i.e. varying gridsizes and dielectric tissue properties. Results: Despite geometrical variations, manual and automatic generated 3D patient models resulted in an equal, i.e. 1%, variation in HTP quality. This variation was minor with respect to the total of other sources of patient model uncertainties, i.e. 11.7%. Conclusions: Automatically generated 3D patient models can be introduced in the clinic for H and N HTP

  12. Preparation of Multifunctional Fe@Au Core-Shell Nanoparticles with Surface Grafting as a Potential Treatment for Magnetic Hyperthermia

    Directory of Open Access Journals (Sweden)

    Ren-Jei Chung

    2014-01-01

    Full Text Available Iron core gold shell nanoparticles grafted with Methotrexate (MTX and indocyanine green (ICG were synthesized for the first time in this study, and preliminarily evaluated for their potential in magnetic hyperthermia treatment. The core-shell Fe@Au nanoparticles were prepared via the microemulsion process and then grafted with MTX and ICG using hydrolyzed poly(styrene-alt-maleic acid (PSMA to obtain core-shell Fe@Au-PSMA-ICG/MTX nanoparticles. MTX is an anti-cancer therapeutic, and ICG is a fluorescent dye. XRD, TEM, FTIR and UV-Vis spectrometry were performed to characterize the nanoparticles. The data indicated that the average size of the nanoparticles was 6.4 ± 09 nm and that the Au coating protected the Fe core from oxidation. MTX and ICG were successfully grafted onto the surface of the nanoparticles. Under exposure to high frequency induction waves, the superparamagnetic nanoparticles elevated the temperature of a solution in a few minutes, which suggested the potential for an application in magnetic hyperthermia treatment. The in vitro studies verified that the nanoparticles were biocompatible; nonetheless, the Fe@Au-PSMA-ICG/MTX nanoparticles killed cancer cells (Hep-G2 via the magnetic hyperthermia mechanism and the release of MTX.

  13. Preparation of Multifunctional Fe@Au Core-Shell Nanoparticles with Surface Grafting as a Potential Treatment for Magnetic Hyperthermia.

    Science.gov (United States)

    Chung, Ren-Jei; Shih, Hui-Ting

    2014-01-24

    Iron core gold shell nanoparticles grafted with Methotrexate (MTX) and indocyanine green (ICG) were synthesized for the first time in this study, and preliminarily evaluated for their potential in magnetic hyperthermia treatment. The core-shell Fe@Au nanoparticles were prepared via the microemulsion process and then grafted with MTX and ICG using hydrolyzed poly(styrene-alt-maleic acid) (PSMA) to obtain core-shell Fe@Au-PSMA-ICG/MTX nanoparticles. MTX is an anti-cancer therapeutic, and ICG is a fluorescent dye. XRD, TEM, FTIR and UV-Vis spectrometry were performed to characterize the nanoparticles. The data indicated that the average size of the nanoparticles was 6.4 ± 09 nm and that the Au coating protected the Fe core from oxidation. MTX and ICG were successfully grafted onto the surface of the nanoparticles. Under exposure to high frequency induction waves, the superparamagnetic nanoparticles elevated the temperature of a solution in a few minutes, which suggested the potential for an application in magnetic hyperthermia treatment. The in vitro studies verified that the nanoparticles were biocompatible; nonetheless, the Fe@Au-PSMA-ICG/MTX nanoparticles killed cancer cells (Hep-G2) via the magnetic hyperthermia mechanism and the release of MTX.

  14. Microwave beamforming for non-invasive patient-specific hyperthermia treatment of pediatric brain cancer

    International Nuclear Information System (INIS)

    Burfeindt, Matthew J; Zastrow, Earl; Hagness, Susan C; Van Veen, Barry D; Medow, Joshua E

    2011-01-01

    We present a numerical study of an array-based microwave beamforming approach for non-invasive hyperthermia treatment of pediatric brain tumors. The transmit beamformer is designed to achieve localized heating-that is, to achieve constructive interference and selective absorption of the transmitted electromagnetic waves at the desired focus location in the brain while achieving destructive interference elsewhere. The design process takes into account patient-specific and target-specific propagation characteristics at 1 GHz. We evaluate the effectiveness of the beamforming approach using finite-difference time-domain simulations of two MRI-derived child head models from the Virtual Family (IT'IS Foundation). Microwave power deposition and the resulting steady-state thermal distribution are calculated for each of several randomly chosen focus locations. We also explore the robustness of the design to mismatch between the assumed and actual dielectric properties of the patient. Lastly, we demonstrate the ability of the beamformer to suppress hot spots caused by pockets of cerebrospinal fluid (CSF) in the brain. Our results show that microwave beamforming has the potential to create localized heating zones in the head models for focus locations that are not surrounded by large amounts of CSF. These promising results suggest that the technique warrants further investigation and development.

  15. Clinical evaluation and verification of the hyperthermia treatment planning system hyperplan

    International Nuclear Information System (INIS)

    Gellermann, Johanna; Wust, Peter; Stalling, Dether; Seebass, Martin; Nadobny, Jacek; Beck, Rudolf; Hege, Hans-Christian; Deuflhard, Peter; Felix, Roland

    2000-01-01

    Purpose: A prototype of the hyperthermia treatment planning system (HTPS) HyperPlan for the SIGMA-60 applicator (BSD Medical Corp., Salt Lake City, Utah, USA) has been evaluated with respect to clinical practicability and correctness. Materials and Methods: HyperPlan modules extract tissue boundaries from computed tomography (CT) images to generate regular and tetrahedral grids as patient models, to calculate electric field (E-field) distributions, and to visualize three-dimensional data sets. The finite difference time-domain (FDTD) method is applied to calculate the specific absorption rate (SAR) inside the patient. Temperature distributions are calculated by a finite-element code and can be optimized. HyperPlan was tested on 6 patients with pelvic tumors. For verification, measured SAR values were compared with calculated SAR values. Furthermore, intracorporeal E-field scans were performed and compared with calculated profiles. Results: The HTPS can be applied under clinical conditions. Measured absolute SAR (in W/kg), as well as relative E-field scans, correlated well with calculated values (±20%) using the contour-based FDTD method. Values calculated by applying the FDTD method directly on the voxel (CT) grid, were less well correlated with measured data. Conclusion: The HyperPlan system proved to be clinically feasible, and the results were quantitatively and qualitatively verified for the contour-based FDTD method

  16. MRI-Guided Focused Ultrasound as a New Method of Drug Delivery

    Directory of Open Access Journals (Sweden)

    M. Thanou

    2013-01-01

    Full Text Available Ultrasound-mediated drug delivery under the guidance of an imaging modality can improve drug disposition and achieve site-specific drug delivery. The term focal drug delivery has been introduced to describe the focal targeting of drugs in tissues with the help of imaging and focused ultrasound. Focal drug delivery aims to improve the therapeutic profile of drugs by improving their specificity and their permeation in defined areas. Focused-ultrasound- (FUS- mediated drug delivery has been applied with various molecules to improve their local distribution in tissues. FUS is applied with the aid of microbubbles to enhance the permeability of bioactive molecules across BBB and improve drug distribution in the brain. Recently, FUS has been utilised in combination with MRI-labelled liposomes that respond to temperature increase. This strategy aims to “activate” nanoparticles to release their cargo locally when triggered by hyperthermia induced by FUS. MRI-guided FUS drug delivery provides the opportunity to improve drug bioavailability locally and therefore improve the therapeutic profiles of drugs. This drug delivery strategy can be directly translated to clinic as MRg FUS is a promising clinically therapeutic approach. However, more basic research is required to understand the physiological mechanism of FUS-enhanced drug delivery.

  17. Simulations of adaptive temperature control with self-focused hyperthermia system for tumor treatment.

    Science.gov (United States)

    Hu, Jiwen; Ding, Yajun; Qian, Shengyou; Tang, Xiangde

    2013-01-01

    The control problem in ultrasound therapy is to destroy the tumor tissue while not harming the intervening healthy tissue with a desired temperature elevation. The objective of this research is to present a robust and feasible method to control the temperature distribution and the temperature elevation in treatment region within the prescribed time, which can improve the curative effect and decrease the treatment time for heating large tumor (≥2.0cm in diameter). An adaptive self-tuning-regulator (STR) controller has been introduced into this control method by adding a time factor with a recursive algorithm, and the speed of sound and absorption coefficient of the medium is considered as a function of temperature during heating. The presented control method is tested for a self-focused concave spherical transducer (0.5MHz, 9cm aperture, 8.0cm focal length) through numerical simulations with three control temperatures of 43°C, 50°C and 55°C. The results suggest that this control system has adaptive ability for variable parameters and has a rapid response to the temperature and acoustic power output in the prescribed time for the hyperthermia interest. There is no overshoot during temperature elevation and no oscillation after reaching the desired temperatures. It is found that the same results can be obtained for different frequencies and temperature elevations. This method can obtain an ellipsoid-shaped ablation region, which is meaningful for the treatment of large tumor. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Improved operative efficiency using a real-time MRI-guided stereotactic platform for laser amygdalohippocampotomy.

    Science.gov (United States)

    Ho, Allen L; Sussman, Eric S; Pendharkar, Arjun V; Le, Scheherazade; Mantovani, Alessandra; Keebaugh, Alaine C; Drover, David R; Grant, Gerald A; Wintermark, Max; Halpern, Casey H

    2018-04-01

    OBJECTIVE MR-guided laser interstitial thermal therapy (MRgLITT) is a minimally invasive method for thermal destruction of benign or malignant tissue that has been used for selective amygdalohippocampal ablation for the treatment of temporal lobe epilepsy. The authors report their initial experience adopting a real-time MRI-guided stereotactic platform that allows for completion of the entire procedure in the MRI suite. METHODS Between October 2014 and May 2016, 17 patients with mesial temporal sclerosis were selected by a multidisciplinary epilepsy board to undergo a selective amygdalohippocampal ablation for temporal lobe epilepsy using MRgLITT. The first 9 patients underwent standard laser ablation in 2 phases (operating room [OR] and MRI suite), whereas the next 8 patients underwent laser ablation entirely in the MRI suite with the ClearPoint platform. A checklist specific to the real-time MRI-guided laser amydalohippocampal ablation was developed and used for each case. For both cohorts, clinical and operative information, including average case times and accuracy data, was collected and analyzed. RESULTS There was a learning curve associated with using this real-time MRI-guided system. However, operative times decreased in a linear fashion, as did total anesthesia time. In fact, the total mean patient procedure time was less in the MRI cohort (362.8 ± 86.6 minutes) than in the OR cohort (456.9 ± 80.7 minutes). The mean anesthesia time was significantly shorter in the MRI cohort (327.2 ± 79.9 minutes) than in the OR cohort (435.8 ± 78.4 minutes, p = 0.02). CONCLUSIONS The real-time MRI platform for MRgLITT can be adopted in an expedient manner. Completion of MRgLITT entirely in the MRI suite may lead to significant advantages in procedural times.

  19. Comparison of two treatments for coxarthrosis: local hyperthermia versus radio electric asymmetrical brain stimulation

    Directory of Open Access Journals (Sweden)

    Castagna A

    2011-07-01

    Full Text Available Alessandro Castagna1, Salvatore Rinaldi1,2, Vania Fontani1, Piero Mannu1, Matteo Lotti Margotti11Rinaldi Fontani Institute, Department of Neuro Psycho Physio Pathology, 2Medical School of Occupational Medicine, University of Florence, Florence, ItalyBackground: It is well known that psychological components are very important in the aging process and may also manifest in psychogenic movement disorders, such as coxarthrosis. This study analyzed the medical records of two similar groups of patients with coxarthrosis (n = 15 in each who were treated in two different clinics for rehabilitation therapy.Methods: Patients in Group A were treated with a course of traditional physiotherapy, including sessions of local hyperthermia. Group B patients were treated with only a course of radioelectric asymmetrical brain stimulation (REAC to improve their motor behavior.Results: Group A showed a significant decrease in symptoms of pain and stiffness, and an insignificant improvement in range of motion and muscle bulk. A single patient in this group developed worsened symptoms, and pain did not resolve completely in any patient. The patients in Group B had significantly decreased levels of pain and stiffness, and a significant improvement in range of motion and muscle bulk. No patients worsened in Group B, and the pain resolved completely in one patient.Conclusion: Both treatments were shown to be tolerable and safe. Patients who underwent REAC treatment appeared to have slightly better outcomes, with an appreciable improvement in both their physical and mental states. These aspects are particularly important in the elderly, in whom functional limitation is often associated with or exacerbated by a psychogenic component.Keywords: coxarthrosis, anti-aging, motor behavior, radioelectric asymmetric brain stimulation

  20. Radiotherapy with or without hyperthermia in the treatment of superficial localized breast cancer: results from five randomized controlled trials

    International Nuclear Information System (INIS)

    Vernon, Clare C.; Hand, Jeffrey W.; Field, Stanley B.; Machin, David; Whaley, Jill B.; Zee, Jacoba van der; Putten, Wim L.J. van; Rhoon, Gerard C. van; Dijk, Jan D.P. van; Gonzalez, Dionisio Gonzalez; Liu, F.-F.; Goodman, Phyllis; Sherar, Michael

    1996-01-01

    Purpose: Claims for the value of hyperthermia as an adjunct to radiotherapy in the treatment of cancer have mostly been based on small Phase I or II trials. To test the benefit of this form of treatment, randomized Phase III trials were needed. Methods and Materials: Five randomized trials addressing this question were started between 1988 and 1991. In these trials, patients were eligible if they had advanced primary or recurrent breast cancer, and local radiotherapy was indicated in preference to surgery. In addition, heating of the lesions and treatment with a prescribed (re)irradiation schedule had to be feasible and informed consent was obtained. The primary endpoint of all trials was local complete response. Slow recruitment led to a decision to collaborate and combine the trial results in one analysis, and report them simultaneously in one publication. Interim analyses were carried out and the trials were closed to recruitment when a previously agreed statistically significant difference in complete response rate was observed in the two larger trials. Results: We report on pretreatment characteristics, the treatments received, the local response observed, duration of response, time to local failure, distant progression and survival, and treatment toxicity of the 306 patients randomized. The overall CR rate for RT alone was 41% and for the combined treatment arm was 59%, giving, after stratification by trial, an odds ratio of 2.3. Not all trials demonstrated an advantage for the combined treatment, although the 95% confidence intervals of the different trials all contain the pooled odds ratio. The greatest effect was observed in patients with recurrent lesions in previously irradiated areas, where further irradiation was limited to low doses. Conclusion: The combined result of the five trials has demonstrated the efficacy of hyperthermia as an adjunct to radiotherapy for treatment of recurrent breast cancer. The implication of these encouraging results is that

  1. Interstitial hyperthermia and iridium-192 treatment alone vs. interstitial iridium-192 treatment/hyperthermia and low dose cisplatinum infusion in the treatment of locally advanced head and neck malignancies

    International Nuclear Information System (INIS)

    Schreiber, David P.; Overett, Thomas K.

    1995-01-01

    Purpose: To determine whether the addition of low dose platinum infusional chemotherapy adds to the effectiveness of interstitial hyperthermia/iridium-192 management of locally advanced head and neck malignancies. Methods and Materials: From 1987 to 1993, 36 patients with locally advanced head and neck malignancies were treated locally with interstitial hyperthermia and iridium-192 as part or all of their management. Twenty-two of the above-mentioned patients also received low dose infusional cisplatinum chemotherapy at 20 mg/M 2 per day during the time of the implant. No patient received greater than 100 mg/M 2 total dose. Implant times ranged from 38.5 to 134 h and total doses delivered with the radiation implants ranged from 15 to 39.9 Gy. Average implant volume was 50 cc. Twenty-three patients received external beam irradiation supplementation in a dose range from 25.2 to 64 Gy. Results: Median follow-up for the entire group was 8, months with 7 months for the chemotherapy group vs. 12 months for the no-chemotherapy group. Freedom from relapse rates for the chemotherapy group vs. the no-chemotherapy group were 70% at 41 months vs. 63% at 60 months, p not significant (p = NS). Overall survival by Life Table Analysis was 28% for the chemotherapy group at 41 months vs. 31% for the no-chemotherapy group at 60 months (p = NS). Complete response (CR) rates were 93% for the chemotherapy group vs. 86% for the no-chemotherapy group. Seven patients in the chemotherapy group had recurrent disease and four patients in the no-chemotherapy group were being treated for recurrent disease. Complication rates were similar in both groups, with two patients in the chemotherapy arm requiring hyperbaric oxygen treatments and one patient in the no-chemotherapy arm requiring hyperbaric oxygen treatments (for soft tissue necrosis). Conclusion: It appears that low dose platinum infusional chemotherapy can be added safely to patients receiving interstitial iridium-192 implants along with

  2. Combination of hyperthermia and radiation in the treatment of experimental tumours in mice

    International Nuclear Information System (INIS)

    Jansen, W.

    1980-01-01

    The effects of hyperthermia as a single agent and in interaction with ionizing radiation are investigated on tumours in mice. The degree of enhancement of the radiation reaction by heat proved to be similar to that found for mouse skin. (Auth.)

  3. TU-B-210-02: MRg HIFU - Advanced Approaches for Ablation and Hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    Moonen, C. [University Medical Center Utrecht (Netherlands)

    2015-06-15

    MR guided focused ultrasound (MRgFUS), or alternatively high-intensity focused ultrasound (MRgHIFU), is approved for thermal ablative treatment of uterine fibroids and pain palliation in bone metastases. Ablation of malignant tumors is under active investigation in sites such as breast, prostate, brain, liver, kidney, pancreas, and soft tissue. Hyperthermia therapy with MRgFUS is also feasible, and may be used in conjunction with radiotherapy and for local targeted drug delivery. MRI allows in situ target definition and provides continuous temperature monitoring and subsequent thermal dose mapping during HIFU. Although MRgHIFU can be very precise, treatment of mobile organs is challenging and advanced techniques are required because of artifacts in MR temperature mapping, the need for intercostal firing, and need for gated HIFU or tracking of the lesion in real time. The first invited talk, “MR guided Focused Ultrasound Treatment of Tumors in Bone and Soft Tissue”, will summarize the treatment protocol and review results from treatment of bone tumors. In addition, efforts to extend this technology to treat both benign and malignant soft tissue tumors of the extremities will be presented. The second invited talk, “MRI guided High Intensity Focused Ultrasound – Advanced Approaches for Ablation and Hyperthermia”, will provide an overview of techniques that are in or near clinical trials for thermal ablation and hyperthermia, with an emphasis of applications in abdominal organs and breast, including methods for MRTI and tracking targets in moving organs. Learning Objectives: Learn background on devices and techniques for MR guided HIFU for cancer therapy Understand issues and current status of clinical MRg HIFU Understand strategies for compensating for organ movement during MRgHIFU Understand strategies for strategies for delivering hyperthermia with MRgHIFU CM - research collaboration with Philips.

  4. Fully automated MRI-guided robotics for prostate brachytherapy

    International Nuclear Information System (INIS)

    Stoianovici, D.; Vigaru, B.; Petrisor, D.; Muntener, M.; Patriciu, A.; Song, D.

    2008-01-01

    The uncertainties encountered in the deployment of brachytherapy seeds are related to the commonly used ultrasound imager and the basic instrumentation used for the implant. An alternative solution is under development in which a fully automated robot is used to place the seeds according to the dosimetry plan under direct MRI-guidance. Incorporation of MRI-guidance creates potential for physiological and molecular image-guided therapies. Moreover, MRI-guided brachytherapy is also enabling for re-estimating dosimetry during the procedure, because with the MRI the seeds already implanted can be localised. An MRI compatible robot (MrBot) was developed. The robot is designed for transperineal percutaneous prostate interventions, and customised for fully automated MRI-guided brachytherapy. With different end-effectors, the robot applies to other image-guided interventions of the prostate. The robot is constructed of non-magnetic and dielectric materials and is electricity free using pneumatic actuation and optic sensing. A new motor (PneuStep) was purposely developed to set this robot in motion. The robot fits alongside the patient in closed-bore MRI scanners. It is able to stay fully operational during MR imaging without deteriorating the quality of the scan. In vitro, cadaver, and animal tests showed millimetre needle targeting accuracy, and very precise seed placement. The robot tested without any interference up to 7T. The robot is the first fully automated robot to function in MRI scanners. Its first application is MRI-guided seed brachytherapy. It is capable of automated, highly accurate needle placement. Extensive testing is in progress prior to clinical trials. Preliminary results show that the robot may become a useful image-guided intervention instrument. (author)

  5. High-resolution temperature-based optimization for hyperthermia treatment planning

    International Nuclear Information System (INIS)

    Kok, H P; Haaren, P M A van; Kamer, J B Van de; Wiersma, J; Dijk, J D P Van; Crezee, J

    2005-01-01

    In regional hyperthermia, optimization techniques are valuable in order to obtain amplitude/phase settings for the applicators to achieve maximal tumour heating without toxicity to normal tissue. We implemented a temperature-based optimization technique and maximized tumour temperature with constraints on normal tissue temperature to prevent hot spots. E-field distributions are the primary input for the optimization method. Due to computer limitations we are restricted to a resolution of 1 x 1 x 1 cm 3 for E-field calculations, too low for reliable treatment planning. A major problem is the fact that hot spots at low-resolution (LR) do not always correspond to hot spots at high-resolution (HR), and vice versa. Thus, HR temperature-based optimization is necessary for adequate treatment planning and satisfactory results cannot be obtained with LR strategies. To obtain HR power density (PD) distributions from LR E-field calculations, a quasi-static zooming technique has been developed earlier at the UMC Utrecht. However, quasi-static zooming does not preserve phase information and therefore it does not provide the HR E-field information required for direct HR optimization. We combined quasi-static zooming with the optimization method to obtain a millimetre resolution temperature-based optimization strategy. First we performed a LR (1 cm) optimization and used the obtained settings to calculate the HR (2 mm) PD and corresponding HR temperature distribution. Next, we performed a HR optimization using an estimation of the new HR temperature distribution based on previous calculations. This estimation is based on the assumption that the HR and LR temperature distributions, though strongly different, respond in a similar way to amplitude/phase steering. To verify the newly obtained settings, we calculate the corresponding HR temperature distribution. This method was applied to several clinical situations and found to work very well. Deviations of this estimation method for

  6. Implant strategies for endocervical and interstitial ultrasound hyperthermia adjunct to HDR brachytherapy for the treatment of cervical cancer

    Science.gov (United States)

    Wootton, Jeffery H.; Prakash, Punit; Hsu, I.-Chow Joe; Diederich, Chris J.

    2011-07-01

    Catheter-based ultrasound devices provide a method to deliver 3D conformable heating integrated with HDR brachytherapy delivery. Theoretical characterization of heating patterns was performed to identify implant strategies for these devices which can best be used to apply hyperthermia to cervical cancer. A constrained optimization-based hyperthermia treatment planning platform was used for the analysis. The proportion of tissue >=41 °C in a hyperthermia treatment volume was maximized with constraints Tmax 200 cm3) is possible using multiple sectored interstitial and endocervical ultrasound devices. The endocervical device can heat >41 °C to 4.6 cm diameter compared to 3.6 cm for the interstitial. Sectored applicators afford tight control of heating that is robust to perfusion changes in most regularly spaced configurations. T90 in example patient cases was 40.5-42.7 °C (1.9-39.6 EM43 °C) at 1 kg m-3 s-1 with 10/14 patients >=41 °C. Guidelines are presented for positioning of implant catheters during the initial surgery, selection of ultrasound applicator configurations, and tailored power schemes for achieving T90 >= 41 °C in clinically practical implant configurations. Catheter-based ultrasound devices, when adhering to the guidelines, show potential to generate conformal therapeutic heating ranging from a single endocervical device targeting small volumes local to the cervix (directional interstitial applicators in the lateral periphery to target much larger volumes (6 cm radial), while preferentially limiting heating of the bladder and rectum.

  7. Implant strategies for endocervical and interstitial ultrasound hyperthermia adjunct to HDR brachytherapy for the treatment of cervical cancer

    International Nuclear Information System (INIS)

    Wootton, Jeffery H; Prakash, Punit; Hsu, I-Chow Joe; Diederich, Chris J

    2011-01-01

    Catheter-based ultrasound devices provide a method to deliver 3D conformable heating integrated with HDR brachytherapy delivery. Theoretical characterization of heating patterns was performed to identify implant strategies for these devices which can best be used to apply hyperthermia to cervical cancer. A constrained optimization-based hyperthermia treatment planning platform was used for the analysis. The proportion of tissue ≥41 deg. C in a hyperthermia treatment volume was maximized with constraints T max ≤ 47 deg. C, T rectum ≤ 41.5 deg. C, and T bladder ≤ 42.5 deg. C. Hyperthermia treatment was modeled for generalized implant configurations and complex configurations from a database of patients (n = 14) treated with HDR brachytherapy. Various combinations of endocervical (360 0 or 2 x 180 0 output; 6 mm OD) and interstitial (180 0 , 270 0 , or 360 0 output; 2.4 mm OD) applicators within catheter locations from brachytherapy implants were modeled, with perfusion constant (1 or 3 kg m -3 s -1 ) or varying with location or temperature. Device positioning, sectoring, active length and aiming were empirically optimized to maximize thermal coverage. Conformable heating of appreciable volumes (>200 cm 3 ) is possible using multiple sectored interstitial and endocervical ultrasound devices. The endocervical device can heat >41 deg. C to 4.6 cm diameter compared to 3.6 cm for the interstitial. Sectored applicators afford tight control of heating that is robust to perfusion changes in most regularly spaced configurations. T 90 in example patient cases was 40.5-42.7 deg. C (1.9-39.6 EM 43deg.C ) at 1 kg m -3 s -1 with 10/14 patients ≥41 deg. C. Guidelines are presented for positioning of implant catheters during the initial surgery, selection of ultrasound applicator configurations, and tailored power schemes for achieving T 90 ≥ 41 deg. C in clinically practical implant configurations. Catheter-based ultrasound devices, when adhering to the guidelines, show

  8. Ultrasound guided pO2 measurement of breast cancer reoxygenation after neoadjuvant chemotherapy and hyperthermia treatment.

    Science.gov (United States)

    Vujaskovic, Z; Rosen, E L; Blackwell, K L; Jones, E L; Brizel, D M; Prosnitz, L R; Samulski, T V; Dewhirst, M W

    2003-01-01

    The objective of this study was to determine whether neoadjuvant chemotherapy in combination with hyperthermia (HT) would improve oxygenation in locally advanced breast tumours. The study describes a new optimized ultrasound guided technique of pO2 measurement using Eppendorf polarographic oxygen probes in 18 stage IIB-III breast cancer patients. Prior to treatment, tumour hypoxia (median pO2pO2=3.2 mmHg). Seven patients had well oxygenated tumours (median pO2 of 48.3 mmHg). Eight patients with hypoxic tumours prior to treatment had a significant improvement (p=0.0008) in tumour pO2 after treatment (pO2 increased to 19.2 mmHg). In three patients, tumours remained hypoxic (average median pO2=4.5 mmHg). The advantages of the ultrasound guided pO2 probe are in the accuracy of the Eppendorf electrode placement in tumour tissue, the ability to monitor electrode movement through the tumour tissue during the measurement and the ability to avoid electrode placement near or in large blood vessels by using colour Doppler imaging. The results of this preliminary study suggest that the combination of neoadjuvant chemotherapy and hyperthermia improves oxygenation in locally advanced breast tumours that are initially hypoxic.

  9. Hyperthermia on skin immune system and its application in the treatment of HPV-infected skin diseases

    Institute of Scientific and Technical Information of China (English)

    Gao Xinghua; Chen Hongduo

    2014-01-01

    In this paper, the effects of hyperthermia on cells and immune system are introduced briefly. The mechanism of action of hyperthermia on human papilloma virus (HPV)-infected skin diseases was elaborated as an example in this paper. Many studies have proved that hyperthermia affects a number of cellular and molecu- lar constitutes in the skin immune system, involving both innate and adaptive immune responses; the efficacy of hyperthermia in treating some infectious and cancerous conditions has been validated and applied in clinics, while molecular mechanisms of hyperthermia affecting the immunereaction is still unclear.

  10. Biological effects of hyperthermia

    International Nuclear Information System (INIS)

    Okumura, Hiroshi

    1980-01-01

    Biological effects of hyperthermia and application of hyperthermia to cancer therapy were outlined. As to independent effects of hyperthermia, heat sensitivity of cancer cells, targets of hyperthermia, thermal tolerance of cancer cells, effects of pH on hyperthermic cell survival, effects of hyperthermia on normal tissues, and possibility of clinical application of hyperthermia were described. Combined effect of hyperthermia and x-irradiation to enhance radiosensitivity of cancer cells, its mechanism, effects of oxygen on cancer cells treated with hyperthermia and irradiation, and therapeutic ratio of combined hyperthermia and irradiation were also described. Finally, sensitizers were mentioned. (Tsunoda, M.)

  11. Temperature mapping and thermal dose calculation in combined radiation therapy and 13.56 MHz radiofrequency hyperthermia for tumor treatment

    Science.gov (United States)

    Kim, Jung Kyung; Prasad, Bibin; Kim, Suzy

    2017-02-01

    To evaluate the synergistic effect of radiotherapy and radiofrequency hyperthermia therapy in the treatment of lung and liver cancers, we studied the mechanism of heat absorption and transfer in the tumor using electro-thermal simulation and high-resolution temperature mapping techniques. A realistic tumor-induced mouse anatomy, which was reconstructed and segmented from computed tomography images, was used to determine the thermal distribution in tumors during radiofrequency (RF) heating at 13.56 MHz. An RF electrode was used as a heat source, and computations were performed with the aid of the multiphysics simulation platform Sim4Life. Experiments were carried out on a tumor-mimicking agar phantom and a mouse tumor model to obtain a spatiotemporal temperature map and thermal dose distribution. A high temperature increase was achieved in the tumor from both the computation and measurement, which elucidated that there was selective high-energy absorption in tumor tissue compared to the normal surrounding tissues. The study allows for effective treatment planning for combined radiation and hyperthermia therapy based on the high-resolution temperature mapping and high-precision thermal dose calculation.

  12. Analysis of clinical data to determine the minimum number of sensors required for adequate skin temperature monitoring of superficial hyperthermia treatments.

    Science.gov (United States)

    Bakker, Akke; Holman, Rebecca; Rodrigues, Dario B; Dobšíček Trefná, Hana; Stauffer, Paul R; van Tienhoven, Geertjan; Rasch, Coen R N; Crezee, Hans

    2018-04-27

    Tumor response and treatment toxicity are related to minimum and maximum tissue temperatures during hyperthermia, respectively. Using a large set of clinical data, we analyzed the number of sensors required to adequately monitor skin temperature during superficial hyperthermia treatment of breast cancer patients. Hyperthermia treatments monitored with >60 stationary temperature sensors were selected from a database of patients with recurrent breast cancer treated with re-irradiation (23 × 2 Gy) and hyperthermia using single 434 MHz applicators (effective field size 351-396 cm 2 ). Reduced temperature monitoring schemes involved randomly selected subsets of stationary skin sensors, and another subset simulating continuous thermal mapping of the skin. Temperature differences (ΔT) between subsets and complete sets of sensors were evaluated in terms of overall minimum (T min ) and maximum (T max ) temperature, as well as T90 and T10. Eighty patients were included yielding a total of 400 hyperthermia sessions. Median ΔT was 50 sensors were used. Subsets of sensors result in underestimation of T max up to -2.1 °C (ΔT 95%CI), which decreased to -0.5 °C when >50 sensors were used. Thermal profiles (8-21 probes) yielded a median ΔT 50 stationary sensors or thermal profiles. Adequate coverage of the skin temperature distribution during superficial hyperthermia treatment requires the use of >50 stationary sensors per 400 cm 2 applicator. Thermal mapping is a valid alternative.

  13. Hyperthermia and hyperglycemia in oncology

    International Nuclear Information System (INIS)

    Zhavrid, Eh.A.; Osinskij, S.P.; Fradkin, S.Z.

    1987-01-01

    Consideration is being given to publication data and results of author's investigations into the effect of hyperthermia and hyperglycemia on physico-chemical characteristics and growth of various experimental tumors. Factors, modifying thermosensitivity, mechanisms of hyperthermia effect, various aspects of thermochimio- and thermoradiotherapy have been analyzed. Effect of artificial hyperglycemia on metabolism and kinetics of tumor and some normal cells is considered in detail. Many data, testifying to sufficient growth of efficiency of oncologic patient treatment under conditions of multimodality therapy including hyperthermia and hyperglycemia are presented

  14. Future of medical physics: Real-time MRI-guided proton therapy.

    Science.gov (United States)

    Oborn, Bradley M; Dowdell, Stephen; Metcalfe, Peter E; Crozier, Stuart; Mohan, Radhe; Keall, Paul J

    2017-08-01

    With the recent clinical implementation of real-time MRI-guided x-ray beam therapy (MRXT), attention is turning to the concept of combining real-time MRI guidance with proton beam therapy; MRI-guided proton beam therapy (MRPT). MRI guidance for proton beam therapy is expected to offer a compelling improvement to the current treatment workflow which is warranted arguably more than for x-ray beam therapy. This argument is born out of the fact that proton therapy toxicity outcomes are similar to that of the most advanced IMRT treatments, despite being a fundamentally superior particle for cancer treatment. In this Future of Medical Physics article, we describe the various software and hardware aspects of potential MRPT systems and the corresponding treatment workflow. Significant software developments, particularly focused around adaptive MRI-based planning will be required. The magnetic interaction between the MRI and the proton beamline components will be a key area of focus. For example, the modeling and potential redesign of a magnetically compatible gantry to allow for beam delivery from multiple angles towards a patient located within the bore of an MRI scanner. Further to this, the accuracy of pencil beam scanning and beam monitoring in the presence of an MRI fringe field will require modeling, testing, and potential further development to ensure that the highly targeted radiotherapy is maintained. Looking forward we envisage a clear and accelerated path for hardware development, leveraging from lessons learnt from MRXT development. Within few years, simple prototype systems will likely exist, and in a decade, we could envisage coupled systems with integrated gantries. Such milestones will be key in the development of a more efficient, more accurate, and more successful form of proton beam therapy for many common cancer sites. © 2017 American Association of Physicists in Medicine.

  15. Development of a new apparatus for MRI guided stereotactic surgery

    International Nuclear Information System (INIS)

    Iwata, Yukiya; Amano, Keiichi; Kawamura, Hirotsune; Tanikawa, Tatsuya; Kawabatake, Hiroko; Iseki, Hiroshi; Kobayashi, Naotoshi; Ono, Yuko

    1990-01-01

    Since Leksell et al. reported the application of NMR imaging to stereotactic surgery, MRI has been used for determination of the coordinates of target in the brain. The image of the MRI, however, is significantly distorted due to non-uniformity of the magnetic field. The authors have devised a new marker system (the imaginary inner marker system) and have also modified the Iseki CT guided stereotactic frame for utilizing MRI. In this system, the imaginary markers were set up inside the brain. The image of the grid phantom, obtained immediately before the operation, is superimposed on the image of a patient's brain. The nearest image of grid phantom is used for MRI localization as an imaginary inner marker. To prevent distortion and resolution degradation on MRI, the localizing system is composed of acrylic resin and titanium. The head ring can be fixed on both the MRI localizing system and the Iseki CT guided stereotactic frame which allows the transformation of target coordinates from the MRI localizing system to the CT guided frame. MRI guided stereotactic surgery, therefore, can be performed while monitoring with the CT scan. The system was tested using a phantom and taking T 1 -weighted images before clinical application. Coordinates of target points were determined accurately to a 2 mm cube. A 47-year-old, right-handed woman underwent a MRI guided biopsy of the right thalamic mass lesion that was more accurately detected by MRI than CT scan. The histological diagnosis was a malignant lymphoma. No complications have occurred. MRI stereotaxy, at the present time, is expected to be most useful in the biopsy of deep-seated brain lesions which are not easily detected by CT scan. In the near future, It will take the place of other imaging techniques during functional neurosurgery, with sufficient accuracy. (author)

  16. Combining chemotherapy and/or hyperthermia with radiation in the treatment of malignant melanoma

    International Nuclear Information System (INIS)

    Douple, E.B.

    1984-01-01

    Radiation survival curves for some but not all human melanoma cells show broad shoulders and recovery of potentially lethal radiation damage (PLD), both in vitro and in situ as xenografts in mice. Studies have also demonstrated a significant hypoxic melanoma cell population. Chemotherapy and/or hyperthermia with radiation offers the potential for additive cell killing plus modification of the terminal slope and/or shoulder as a result of supra-additive killing via radiosensitization of hypoxic cells and/or post-irradiation inhibition of cellular recovery from PLD. Such interactions should provide a therapeutic gain factor, expecially if the long-term normal tissue damage is not based on PLD repair. Higher radiation doses per fraction warrant use of PLD recovery inhibitors and would accommodate a practical consideration for the use of fewer drug/heat doses. Peak heat or drug concentrations should probably be present just before and immediately following irradiation. This paper reviews the radiobiological experiments to support the rationale for the addition of chemotherapy and/or hyperthermia to melanoma. The author stresses the problems which remain including the paucity of appropriate preclinical experiments as well as clinical problems of tumor heterogeneity, pharmacokinetics and anatomy

  17. MRI-guided prostate focal laser ablation therapy using a mechatronic needle guidance system

    Science.gov (United States)

    Cepek, Jeremy; Lindner, Uri; Ghai, Sangeet; Davidson, Sean R. H.; Trachtenberg, John; Fenster, Aaron

    2014-03-01

    Focal therapy of localized prostate cancer is receiving increased attention due to its potential for providing effective cancer control in select patients with minimal treatment-related side effects. Magnetic resonance imaging (MRI)-guided focal laser ablation (FLA) therapy is an attractive modality for such an approach. In FLA therapy, accurate placement of laser fibers is critical to ensuring that the full target volume is ablated. In practice, error in needle placement is invariably present due to pre- to intra-procedure image registration error, needle deflection, prostate motion, and variability in interventionalist skill. In addition, some of these sources of error are difficult to control, since the available workspace and patient positions are restricted within a clinical MRI bore. In an attempt to take full advantage of the utility of intraprocedure MRI, while minimizing error in needle placement, we developed an MRI-compatible mechatronic system for guiding needles to the prostate for FLA therapy. The system has been used to place interstitial catheters for MRI-guided FLA therapy in eight subjects in an ongoing Phase I/II clinical trial. Data from these cases has provided quantification of the level of uncertainty in needle placement error. To relate needle placement error to clinical outcome, we developed a model for predicting the probability of achieving complete focal target ablation for a family of parameterized treatment plans. Results from this work have enabled the specification of evidence-based selection criteria for the maximum target size that can be confidently ablated using this technique, and quantify the benefit that may be gained with improvements in needle placement accuracy.

  18. Modification of radiosensitivity of mammalian cells by means of hyperthermia and chemical agent. Coordinated programme on improvement of cancer therapy by the combination of treatment by conventional radiation and physical or chemical means

    International Nuclear Information System (INIS)

    Djordjevic, O.

    1984-11-01

    The effect of the treatment of the cultured mammalian cells with a relatively new anti-cancer drug teniposide (VM26), radiation (4 Gy), hyperthermia (42 deg. C and 45 deg. C) and caffeine, in various combinations, has been studied. The following conclusions can be drawn from the data obtained: The cultured mammalian cells respond to the anti-cancer drug VM26 treatment in a dose and time dependent manner. Significant potentiation of cell killing was demonstrated when they are exposed simultaneously to VM26 and hyperthermia. Post-treatment incubation of the cells in non-toxic concentration of caffeine (2 mM) has produced a marked potentiation of the lethal effect, indicating that caffeine interferes with the repair processes in these cells. Combination of VM26, hyperthermia and caffeine produced a maximum killing effect compared to VM26 treatment only. When the cells are exposed to initial (90 min. at 42 deg. C or 40 min. at 45 deg. C) and subsequent hyperthermia (60 min. at 42 deg. C or 60 min. at 45 deg. C) the thermotolerance will develop depending on the degree of initial and subsequent temperature. The combination of hyperthermia with irradiation results in a potentiation of the effect of treatment compared to the treatment with only irradiation or hyperthermia. Maximum killing of the cells will be obtained when irradiation is applied immediately after hyperthermia. The results obtained should be regarded as useful in case of clinical application of the tested agents

  19. Proliferation kinetics and survival of mammal cells after treatment with radiation of various ionization densities and with hyperthermia

    International Nuclear Information System (INIS)

    Schlag, H.

    1977-01-01

    Survival and proliferation kinetics of chinese hamster cells after Co-γ-, π - -meson irradiation, hyperthermia (40 - 43 0 C), and a combination of Co-γ irradiation and hyperthermia were studied in this paper. After γ-irradiation, exponential-phase and stationary-phase cells showed equal survival rates for equal doses. Cytofluorometric analysis showed that there was a dose-dependent delay in the synthesis phase with subsequent cell blocking in the G 2 +M phase. After irradiation with π - mesons, there is a dose-dependent accumulation in the G 2 +M phase, with a RBE of 2.2. The different response of S-phase cells to radiations of different LET may be explained with the inactivation kinetics typical of each type of radiation. The effectiveness of hyperthermal treatment depends on the stage of growth of the cells. A temperature of 40 0 C does not induce cell killing, not even after prolonged exposure. After 7 hours' exposure to 41 0 C, on the other hand, 80% of the cells are killed after blocking in G 2 +M. Exposure to 42 0 C for 1-2 h induces a synchronisation effect which is induced by a block in S and G 2 +M. After exposure to 42 0 C for 4 h, however, the cells blocked in S are killed in this phase. Combination of Co-γ radiation leads to increased cells killing and also to sensitization, especially of cells in the exponential growth stage. The proliferation kinetics effects of this combined treatment are the same as after pion irradiation. (orig.) [de

  20. Improvement of drug delivery by hyperthermia treatment using magnetic cubic cobalt ferrite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Dey, Chaitali, E-mail: chaitalidey29@gmail.com [Centre for Research in Nanoscience & Nanotechnology, Block-JD-2, Sector-III, Salt Lake, Kolkata 700106 (India); Baishya, Kaushik [S.N. Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata 700106 (India); Ghosh, Arup [S.N. Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata 700106 (India); Department of Physics, Indian Institute of Science Education and Research (IISER) Pune, Dr. Homi Bhabha Road, Pashan, Pune 411008 (India); Goswami, Madhuri Mandal, E-mail: madhuri@bose.res.in [S.N. Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata 700106 (India); Ghosh, Ajay [Dept. of Applied Optics and Photonics, University of Calcutta, Block-JD-2, Sector-III, Salt Lake, Kolkata 700106 (India); Mandal, Kalyan [S.N. Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata 700106 (India)

    2017-04-01

    In this study, we report a novel synthesis method, characterization and application of a new class of ferromagnetic cubic cobalt ferrite magnetic nanoparticles (MNPs) for hyperthermia therapy and temperature triggered drug release. The MNPs are characterized by XRD, TEM, FESEM, AC magnetic hysteresis and VSM. These MNPs were coated with folic acid and loaded with an anticancer drug. The drug release studies were done at two different temperatures (37 °C and 44 °C) with progress of time. It was found that higher release of drug took place at elevated temperature (44 °C). We have developed a temperature sensitive drug delivery system which releases the heat sensitive drug selectively as the particles are heated up under AC magnetic field and controlled release is possible by changing the external AC magnetic field.

  1. Temperature simulations in hyperthermia treatment planning of the head and neck region. Rigorous optimization of tissue properties

    International Nuclear Information System (INIS)

    Verhaart, Rene F.; Rijnen, Zef; Verduijn, Gerda M.; Paulides, Margarethus M.; Fortunati, Valerio; Walsum, Theo van; Veenland, Jifke F.

    2014-01-01

    Hyperthermia treatment planning (HTP) is used in the head and neck region (H and N) for pretreatment optimization, decision making, and real-time HTP-guided adaptive application of hyperthermia. In current clinical practice, HTP is based on power-absorption predictions, but thermal dose-effect relationships advocate its extension to temperature predictions. Exploitation of temperature simulations requires region- and temperature-specific thermal tissue properties due to the strong thermoregulatory response of H and N tissues. The purpose of our work was to develop a technique for patient group-specific optimization of thermal tissue properties based on invasively measured temperatures, and to evaluate the accuracy achievable. Data from 17 treated patients were used to optimize the perfusion and thermal conductivity values for the Pennes bioheat equation-based thermal model. A leave-one-out approach was applied to accurately assess the difference between measured and simulated temperature (∇T). The improvement in ∇T for optimized thermal property values was assessed by comparison with the ∇T for values from the literature, i.e., baseline and under thermal stress. The optimized perfusion and conductivity values of tumor, muscle, and fat led to an improvement in simulation accuracy (∇T: 2.1 ± 1.2 C) compared with the accuracy for baseline (∇T: 12.7 ± 11.1 C) or thermal stress (∇T: 4.4 ± 3.5 C) property values. The presented technique leads to patient group-specific temperature property values that effectively improve simulation accuracy for the challenging H and N region, thereby making simulations an elegant addition to invasive measurements. The rigorous leave-one-out assessment indicates that improvements in accuracy are required to rely only on temperature-based HTP in the clinic. (orig.) [de

  2. Three-Dimensional Microwave Hyperthermia for Breast Cancer Treatment in a Realistic Environment Using Particle Swarm Optimization.

    Science.gov (United States)

    Nguyen, Phong Thanh; Abbosh, Amin; Crozier, Stuart

    2017-06-01

    In this paper, a technique for noninvasive microwave hyperthermia treatment for breast cancer is presented. In the proposed technique, microwave hyperthermia of patient-specific breast models is implemented using a three-dimensional (3-D) antenna array based on differential beam-steering subarrays to locally raise the temperature of the tumor to therapeutic values while keeping healthy tissue at normal body temperature. This approach is realized by optimizing the excitations (phases and amplitudes) of the antenna elements using the global optimization method particle swarm optimization. The antennae excitation phases are optimized to maximize the power at the tumor, whereas the amplitudes are optimized to accomplish the required temperature at the tumor. During the optimization, the technique ensures that no hotspots exist in healthy tissue. To implement the technique, a combination of linked electromagnetic and thermal analyses using MATLAB and the full-wave electromagnetic simulator is conducted. The technique is tested at 4.2 GHz, which is a compromise between the required power penetration and focusing, in a realistic simulation environment, which is built using a 3-D antenna array of 4 × 6 unidirectional antenna elements. The presented results on very dense 3-D breast models, which have the realistic dielectric and thermal properties, validate the capability of the proposed technique in focusing power at the exact location and volume of tumor even in the challenging cases where tumors are embedded in glands. Moreover, the models indicate the capability of the technique in dealing with tumors at different on- and off-axis locations within the breast with high efficiency in using the microwave power.

  3. Hyperthermia: clinical results

    International Nuclear Information System (INIS)

    Bicher, H.I.

    1982-01-01

    A large number of patients have now been entered into a phase I/II protocol to examine the effects of fractionated hyperthermia and radiation on tumor response. Included in the study were 11 different histologies with anatomical locations varying between peripheral and superficial metastases to deep-seated, solid tumors. Patients were treated with four fractions of microwave-induced hyperthermia (45.0 +- 0.5 0 C), each separated by intervals of 72 hours. Microwaves at frequencies of 915 MHz or 300 MHz were employed, Patients were given a one week rest following the first four treatments, following which a second series of four fractions were administered, again at 72 hour intervals. Each of these fractions consisted of a 400 rad dose of radiation followed within 20 min by hyperthermia (42.5 +- 5 0 C) for 1.5 hours. To date 121 fields have been treated by 82 patients. Total regression is seen in 65% of all cases, partial regression in 35% and no response is seen in only 5% of treatments. Adverse effects were rare. Site specific trials are currently in progress to study the feasibility of deep-seated heating with intracavitary antennae as well as to assess tumor response. In addition, a randomized trial to examine the clinical relevance of thermotolerance has been started

  4. Hyperthermia and radiotherapy

    International Nuclear Information System (INIS)

    Dietzel, F.

    1979-01-01

    Of decisive importance for superadditive enhancement is the close temporal correlation of hyperthermia and radiotherapy. It is recommended to first irradiate and then use heat treatment in order to ensure that dividable tumour cells are irradiated before hyperthermia. To achieve an optimal enhancing effect, temperatures of appr. 42 0 are sufficient. In order to be able to neglect temperature regulation and convection effects, hyperthermia for clinical use must be carried out in doses high enough to ensure that it can be finished within 3-4 minutes. It is necessary to make efforts to find out which forms of application can be realised in order to reach deeper tissue regions, thus making possible at least a half-depth-therapy. Up to day, only the 2 cm near to the surface can be heated in a sufficiently homogeneous way. In the FRG, there are more than 200 high-volt-therapy systems, including electron accelerators and telegamma systems. This is a dense network of radiation-therapeutical supply. An improved therapy effect of loose ionising rays which, with the help of the hypertherming, would almost be equal to irradiation with high ionisation density, is not only of scientific interest, but also of high interest for public health. (orig./MG) 891 MG/orig.- 892 RDG [de

  5. Temperature simulations in hyperthermia treatment planning of the head and neck region. Rigorous optimization of tissue properties

    Energy Technology Data Exchange (ETDEWEB)

    Verhaart, Rene F.; Rijnen, Zef; Verduijn, Gerda M.; Paulides, Margarethus M. [Erasmus MC - Cancer Institute, Department of Radiation Oncology, Hyperthermia Unit, Rotterdam (Netherlands); Fortunati, Valerio; Walsum, Theo van; Veenland, Jifke F. [Erasmus MC, Departments of Medical Informatics and Radiology, Biomedical Imaging Group Rotterdam, Rotterdam (Netherlands)

    2014-12-15

    Hyperthermia treatment planning (HTP) is used in the head and neck region (H and N) for pretreatment optimization, decision making, and real-time HTP-guided adaptive application of hyperthermia. In current clinical practice, HTP is based on power-absorption predictions, but thermal dose-effect relationships advocate its extension to temperature predictions. Exploitation of temperature simulations requires region- and temperature-specific thermal tissue properties due to the strong thermoregulatory response of H and N tissues. The purpose of our work was to develop a technique for patient group-specific optimization of thermal tissue properties based on invasively measured temperatures, and to evaluate the accuracy achievable. Data from 17 treated patients were used to optimize the perfusion and thermal conductivity values for the Pennes bioheat equation-based thermal model. A leave-one-out approach was applied to accurately assess the difference between measured and simulated temperature (∇T). The improvement in ∇T for optimized thermal property values was assessed by comparison with the ∇T for values from the literature, i.e., baseline and under thermal stress. The optimized perfusion and conductivity values of tumor, muscle, and fat led to an improvement in simulation accuracy (∇T: 2.1 ± 1.2 C) compared with the accuracy for baseline (∇T: 12.7 ± 11.1 C) or thermal stress (∇T: 4.4 ± 3.5 C) property values. The presented technique leads to patient group-specific temperature property values that effectively improve simulation accuracy for the challenging H and N region, thereby making simulations an elegant addition to invasive measurements. The rigorous leave-one-out assessment indicates that improvements in accuracy are required to rely only on temperature-based HTP in the clinic. (orig.) [German] Die Hyperthermiebehandlungsplanung (HTP, ''hyperthermia treatment planning'') wird in der Kopf- und Halsregion zur Optimierung der

  6. A smart platform for hyperthermia application in cancer treatment: cobalt-doped ferrite nanoparticles mineralized in human ferritin cages.

    Science.gov (United States)

    Fantechi, Elvira; Innocenti, Claudia; Zanardelli, Matteo; Fittipaldi, Maria; Falvo, Elisabetta; Carbo, Miriam; Shullani, Valbona; Di Cesare Mannelli, Lorenzo; Ghelardini, Carla; Ferretti, Anna Maria; Ponti, Alessandro; Sangregorio, Claudio; Ceci, Pierpaolo

    2014-05-27

    Magnetic nanoparticles, MNPs, mineralized within a human ferritin protein cage, HFt, can represent an appealing platform to realize smart therapeutic agents for cancer treatment by drug delivery and magnetic fluid hyperthermia, MFH. However, the constraint imposed by the inner diameter of the protein shell (ca. 8 nm) prevents its use as heat mediator in MFH when the MNPs comprise pure iron oxide. In this contribution, we demonstrate how this limitation can be overcome through the controlled doping of the core with small amount of Co(II). Highly monodisperse doped iron oxide NPs with average size of 7 nm are mineralized inside a genetically modified variant of HFt, carrying several copies of α-melanocyte-stimulating hormone peptide, which has already been demonstrated to have excellent targeting properties toward melanoma cells. HFt is also conjugated to poly(ethylene glycol) molecules to increase its in vivo stability. The investigation of hyperthermic properties of HFt-NPs shows that a Co doping of 5% is enough to strongly enhance the magnetic anisotropy and thus the hyperthermic efficiency with respect to the undoped sample. In vitro tests performed on B16 melanoma cell line demonstrate a strong reduction of the cell viability after treatment with Co doped HFt-NPs and exposure to the alternating magnetic field. Clear indications of an advanced stage of apoptotic process is also observed from immunocytochemistry analysis. The obtained data suggest this system represents a promising candidate for the development of a protein-based theranostic nanoplatform.

  7. Thermal wave propagation in blood perfused tissues under hyperthermia treatment for unique oscillatory heat flux at skin surface and appropriate initial condition

    Science.gov (United States)

    Dutta, Jaideep; Kundu, Balaram

    2018-05-01

    This paper aims to develop an analytical study of heat propagation in biological tissues for constant and variable heat flux at the skin surface correlated with Hyperthermia treatment. In the present research work we have attempted to impose two unique kind of oscillating boundary condition relevant to practical aspect of the biomedical engineering while the initial condition is constructed as spatially dependent according to a real life situation. We have implemented Laplace's Transform method (LTM) and Green Function (GFs) method to solve single phase lag (SPL) thermal wave model of bioheat equation (TWMBHE). This research work strongly focuses upon the non-invasive therapy by employing oscillating heat flux. The heat flux at the skin surface is considered as constant, sinusoidal, and cosine forms. A comparative study of the impact of different kinds of heat flux on the temperature field in living tissue explored that sinusoidal heat flux will be more effective if the time of therapeutic heating is high. Cosine heating is also applicable in Hyperthermia treatment due to its precision in thermal waveform. The result also emphasizes that accurate observation must be required for the selection of phase angle and frequency of oscillating heat flux. By possible comparison with the published experimental research work and published mathematical study we have experienced a difference in temperature distribution as 5.33% and 4.73%, respectively. A parametric analysis has been devoted to suggest an appropriate procedure of the selection of important design variables in viewpoint of an effective heating in hyperthermia treatment.

  8. MRI-guided percutaneous retrograde drilling of osteochondritis dissecans of the talus: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Kerimaa, Pekka; Ojala, Risto; Markkanen, Paula; Tervonen, Osmo; Blanco Sequeiros, Roberto [Oulu University Hospital, Department of Radiology, Oulu (Finland); Sinikumpu, Juha-Jaakko; Korhonen, Jussi [Oulu University Hospital, Department of Paediatric Surgery, Oulu (Finland); Hyvoenen, Pekka [Oulu University Hospital, Department of Surgery, Oulu (Finland)

    2014-07-15

    The purpose of this study was to evaluate the feasibility of MRI guidance for percutaneous retrograde drilling in the treatment of osteochondritis dissecans of the talus (OCDT). Four patients, one juvenile and three adults, with one OCDT lesion each and persisting ankle pain after conservative treatment, were treated with MRI-guided retrograde drilling. All lesions were stable and located in the middle or posterior medial third of the talar dome. Pain relief and the ability to return to normal activities were assessed during clinical follow-up. MRI and plain film radiographs were used for imaging follow-up. Technical success was 100 % with no complications and with no damage to the overlying cartilage. All patients experienced some clinical benefit, although only one had complete resolution of pain and one had a relapse leading to surgical treatment. Changes in the pathological imaging findings were mostly very slight during the follow-up period. MRI guidance seems accurate, safe and technically feasible for retrograde drilling of OCDT. Larger series are needed to reliably assess its clinical value. (orig.)

  9. MRI-guided percutaneous retrograde drilling of osteochondritis dissecans of the talus: a feasibility study

    International Nuclear Information System (INIS)

    Kerimaa, Pekka; Ojala, Risto; Markkanen, Paula; Tervonen, Osmo; Blanco Sequeiros, Roberto; Sinikumpu, Juha-Jaakko; Korhonen, Jussi; Hyvoenen, Pekka

    2014-01-01

    The purpose of this study was to evaluate the feasibility of MRI guidance for percutaneous retrograde drilling in the treatment of osteochondritis dissecans of the talus (OCDT). Four patients, one juvenile and three adults, with one OCDT lesion each and persisting ankle pain after conservative treatment, were treated with MRI-guided retrograde drilling. All lesions were stable and located in the middle or posterior medial third of the talar dome. Pain relief and the ability to return to normal activities were assessed during clinical follow-up. MRI and plain film radiographs were used for imaging follow-up. Technical success was 100 % with no complications and with no damage to the overlying cartilage. All patients experienced some clinical benefit, although only one had complete resolution of pain and one had a relapse leading to surgical treatment. Changes in the pathological imaging findings were mostly very slight during the follow-up period. MRI guidance seems accurate, safe and technically feasible for retrograde drilling of OCDT. Larger series are needed to reliably assess its clinical value. (orig.)

  10. Malignant hyperthermia

    Directory of Open Access Journals (Sweden)

    Pollock Neil

    2007-04-01

    Full Text Available Abstract Malignant hyperthermia (MH is a pharmacogenetic disorder of skeletal muscle that presents as a hypermetabolic response to potent volatile anesthetic gases such as halothane, sevoflurane, desflurane and the depolarizing muscle relaxant succinylcholine, and rarely, in humans, to stresses such as vigorous exercise and heat. The incidence of MH reactions ranges from 1:5,000 to 1:50,000–100,000 anesthesias. However, the prevalence of the genetic abnormalities may be as great as one in 3,000 individuals. MH affects humans, certain pig breeds, dogs, horses, and probably other animals. The classic signs of MH include hyperthermia to marked degree, tachycardia, tachypnea, increased carbon dioxide production, increased oxygen consumption, acidosis, muscle rigidity, and rhabdomyolysis, all related to a hypermetabolic response. The syndrome is likely to be fatal if untreated. Early recognition of the signs of MH, specifically elevation of end-expired carbon dioxide, provides the clinical diagnostic clues. In humans the syndrome is inherited in autosomal dominant pattern, while in pigs in autosomal recessive. The pathophysiologic changes of MH are due to uncontrolled rise of myoplasmic calcium, which activates biochemical processes related to muscle activation. Due to ATP depletion, the muscle membrane integrity is compromised leading to hyperkalemia and rhabdomyolysis. In most cases, the syndrome is caused by a defect in the ryanodine receptor. Over 90 mutations have been identified in the RYR-1 gene located on chromosome 19q13.1, and at least 25 are causal for MH. Diagnostic testing relies on assessing the in vitro contracture response of biopsied muscle to halothane, caffeine, and other drugs. Elucidation of the genetic changes has led to the introduction, on a limited basis so far, of genetic testing for susceptibility to MH. As the sensitivity of genetic testing increases, molecular genetics will be used for identifying those at risk with

  11. Complaint-adaptive power density optimization as a tool for HTP-guided steering in deep hyperthermia treatment of pelvic tumors

    International Nuclear Information System (INIS)

    Canters, R A M; Franckena, M; Zee, J van der; Rhoon, G C van

    2008-01-01

    For an efficient clinical use of HTP (hyperthermia treatment planning), optimization methods are needed. In this study, a complaint-adaptive PD (power density) optimization as a tool for HTP-guided steering in deep hyperthermia of pelvic tumors is developed and tested. PD distribution in patients is predicted using FE-models. Two goal functions, Opt1 and Opt2, are applied to optimize PD distributions. Optimization consists of three steps: initial optimization, adaptive optimization after a first complaint and increasing the weight of a region after recurring complaints. Opt1 initially considers only target PD whereas Opt2 also takes into account hot spots. After patient complaints though, both limit PD in a region. Opt1 and Opt2 are evaluated in a phantom test, using patient models and during hyperthermia treatment. The phantom test and a sensitivity study in ten patient models, show that HTP-guided steering is most effective in peripheral complaint regions. Clinical evaluation in two groups of five patients shows that time between complaints is longer using Opt2 (p = 0.007). However, this does not lead to significantly different temperatures (T50s of 40.3 (Opt1) versus 40.1 deg. C (Opt2) (p = 0.898)). HTP-guided steering is feasible in terms of PD reduction in complaint regions and in time consumption. Opt2 is preferable in future use, because of better complaint reduction and control.

  12. Targeting DNA double strand break repair with hyperthermia and DNA-PKcs inhibition to enhance the effect of radiation treatment.

    Science.gov (United States)

    van Oorschot, Bregje; Granata, Giovanna; Di Franco, Simone; Ten Cate, Rosemarie; Rodermond, Hans M; Todaro, Matilde; Medema, Jan Paul; Franken, Nicolaas A P

    2016-10-04

    Radiotherapy is based on the induction of lethal DNA damage, primarily DNA double-strand breaks (DSB). Efficient DSB repair via Non-Homologous End Joining or Homologous Recombination can therefore undermine the efficacy of radiotherapy. By suppressing DNA-DSB repair with hyperthermia (HT) and DNA-PKcs inhibitor NU7441 (DNA-PKcsi), we aim to enhance the effect of radiation.The sensitizing effect of HT for 1 hour at 42°C and DNA-PKcsi [1 μM] to radiation treatment was investigated in cervical and breast cancer cells, primary breast cancer sphere cells (BCSCs) enriched for cancer stem cells, and in an in vivo human tumor model. A significant radio-enhancement effect was observed for all cell types when DNA-PKcsi and HT were applied separately, and when both were combined, HT and DNA-PKcsi enhanced radio-sensitivity to an even greater extent. Strikingly, combined treatment resulted in significantly lower survival rates, 2 to 2.5 fold increase in apoptosis, more residual DNA-DSB 6 h post treatment and a G2-phase arrest. In addition, tumor growth analysis in vivo showed significant reduction in tumor growth and elevated caspase-3 activity when radiation was combined with HT and DNA-PKcsi compared to radiation alone. Importantly, no toxic side effects of HT or DNA-PKcsi were found.In conclusion, inhibiting DNA-DSB repair using HT and DNA-PKcsi before radiotherapy leads to enhanced cytotoxicity in cancer cells. This effect was even noticed in the more radio-resistant BCSCs, which are clearly sensitized by combined treatment. Therefore, the addition of HT and DNA-PKcsi to conventional radiotherapy is promising and might contribute to more efficient tumor control and patient outcome.

  13. Multi-Channel RF System for MRI-Guided Transurethral Ultrasound Thermal Therapy

    Science.gov (United States)

    Yak, Nicolas; Asselin, Matthew; Chopra, Rajiv; Bronskill, Michael

    2009-04-01

    MRI-guided transurethral ultrasound thermal therapy is an approach to treating localized prostate cancer which targets precise deposition of thermal energy within a confined region of the gland. This treatment requires a system incorporating a heating applicator with multiple planar ultrasound transducers and associated RF electronics to control individual elements independently in order to achieve accurate 3D treatment. We report the design, construction, and characterization of a prototype multi-channel system capable of controlling 16 independent RF signals for a 16-element heating applicator. The main components are a control computer, microcontroller, and a 16-channel signal generator with 16 amplifiers, each incorporating a low-pass filter and transmitted/reflected power detection circuit. Each channel can deliver from 0.5 to 10 W of electrical power and good linearity from 3 to 12 MHz. Harmonic RF signals near the Larmor frequency of a 1.5 T MRI were measured to be below -30 dBm and heating experiments within the 1.5 T MR system showed no significant decrease in SNR of the temperature images. The frequency and power for all 16 channels could be changed in less than 250 ms, which was sufficiently rapid for proper performance of the control algorithms. A common backplane design was chosen which enabled an inexpensive, modular approach for each channel resulting in an overall system with minimal footprint.

  14. MRI-guided vacuum-assisted breast biopsy: comparison with stereotactically guided and ultrasound-guided techniques

    Energy Technology Data Exchange (ETDEWEB)

    Imschweiler, Thomas; Freiwald, Bianka; Kubik-Huch, Rahel A. [Kantonspital Baden AG, Institute for Radiology, Baden (Switzerland); Haueisen, Harald [Kantonspital Aarau AG, Institute for Radiology, Aarau (Switzerland); Kampmann, Gert [Clinica Sant' Anna, Lugano, Sorengo (Switzerland); Rageth, Luzi [Adjumed Services AG, Zurich (Switzerland); Seifert, Burkhardt [Institute for Social and Preventive Medicine, University of Zurich, Division of Biostatistics, Zuerich (Switzerland); Rageth, Christoph [Breast Centre, Zurich (Switzerland)

    2014-01-15

    To analyse the development of MRI-guided vacuum-assisted biopsy (VAB) in Switzerland and to compare the procedure with stereotactically guided and ultrasound-guided VAB. We performed a retrospective analysis of VABs between 2009 and 2011. A total of 9,113 VABs were performed. Of these, 557 were MRI guided. MRI-guided VAB showed the highest growth rate (97 %) of all three procedures. The technical success rates for MRI-guided, stereotactically guided and ultrasound-guided VAB were 98.4 % (548/557), 99.1 % (5,904/5,960) and 99.6 % (2,585/2,596), respectively. There were no significant differences (P = 0.12) between the MRI-guided and the stereotactically guided procedures. The technical success rate for ultrasound-guided VAB was significantly higher than that for MRI-guided VAB (P < 0.001). There were no complications using MRI-guided VAB requiring open surgery. The malignancy diagnosis rate for MRI-guided VAB was similar to that for stereotactically guided VAB (P = 0.35). MRI-guided VAB is a safe and accurate procedure that provides insight into clinical breast findings. (orig.)

  15. Application and possible mechanisms of combining LLLT (low level laser therapy), infrared hyperthermia and ionizing radiation in the treatment of cancer

    Science.gov (United States)

    Abraham, Edward H.; Woo, Van H.; Harlin-Jones, Cheryl; Heselich, Anja; Frohns, Florian

    2014-02-01

    Benefit of concomitant infrared hyperthermia and low level laser therapy and ionizing radiation is evaluated in this study. The purpose/objectives: presentation with locally advanced bulky superficial tumors is clinically challenging. To enhance the efficacy of chemotherapy and IMRT (intensity-modulated radiation therapy) and/or electron beam therapy we have developed an inexpensive and clinically effective infrared hyperthermia approach that combines black-body infrared radiation with halogen spectrum radiation and discrete wave length infrared clinical lasers LLLT. The goal is to produce a composite spectrum extending from the far infrared to near infrared and portions of the visible spectrum with discrete penetrating wavelengths generated by the clinical infrared lasers with frequencies of 810 nm and/or 830 nm. The composite spectrum from these sources is applied before and after radiation therapy. We monitor the surface and in some cases deeper temperatures with thermal probes, but use an array of surface probes as the limiting safe thermal constraint in patient treatment while at the same time maximizing infrared entry to deeper tissue layers. Fever-grade infrared hyperthermia is produced in the first centimeters while non-thermal infrared effects act at deeper tissue layers. The combination of these effects with ionizing radiation leads to improved tumor control in many cancers.

  16. Integrated navigation and control software system for MRI-guided robotic prostate interventions.

    Science.gov (United States)

    Tokuda, Junichi; Fischer, Gregory S; DiMaio, Simon P; Gobbi, David G; Csoma, Csaba; Mewes, Philip W; Fichtinger, Gabor; Tempany, Clare M; Hata, Nobuhiko

    2010-01-01

    A software system to provide intuitive navigation for MRI-guided robotic transperineal prostate therapy is presented. In the system, the robot control unit, the MRI scanner, and the open-source navigation software are connected together via Ethernet to exchange commands, coordinates, and images using an open network communication protocol, OpenIGTLink. The system has six states called "workphases" that provide the necessary synchronization of all components during each stage of the clinical workflow, and the user interface guides the operator linearly through these workphases. On top of this framework, the software provides the following features for needle guidance: interactive target planning; 3D image visualization with current needle position; treatment monitoring through real-time MR images of needle trajectories in the prostate. These features are supported by calibration of robot and image coordinates by fiducial-based registration. Performance tests show that the registration error of the system was 2.6mm within the prostate volume. Registered real-time 2D images were displayed 1.97 s after the image location is specified. Copyright 2009 Elsevier Ltd. All rights reserved.

  17. Integrated navigation and control software system for MRI-guided robotic prostate interventions

    Science.gov (United States)

    Tokuda, Junichi; Fischer, Gregory S.; DiMaio, Simon P.; Gobbi, David G.; Csoma, Csaba; Mewes, Philip W.; Fichtinger, Gabor; Tempany, Clare M.; Hata, Nobuhiko

    2010-01-01

    A software system to provide intuitive navigation for MRI-guided robotic transperineal prostate therapy is presented. In the system, the robot control unit, the MRI scanner, and the open-source navigation software are connected together via Ethernet to exchange commands, coordinates, and images using an open network communication protocol, OpenIGTLink. The system has six states called “workphases” that provide the necessary synchronization of all components during each stage of the clinical workflow, and the user interface guides the operator linearly through these workphases. On top of this framework, the software provides the following features for needle guidance: interactive target planning; 3D image visualization with current needle position; treatment monitoring through real-time MR images of needle trajectories in the prostate. These features are supported by calibration of robot and image coordinates by fiducial-based registration. Performance tests show that the registration error of the system was 2.6 mm within the prostate volume. Registered real-time 2D images were displayed 1.97 s after the image location is specified. PMID:19699057

  18. Utility and translatability of mathematical modeling, cell culture and small and large animal models in magnetic nanoparticle hyperthermia cancer treatment research

    Science.gov (United States)

    Hoopes, P. J.; Petryk, Alicia A.; Misra, Adwiteeya; Kastner, Elliot J.; Pearce, John A.; Ryan, Thomas P.

    2015-03-01

    For more than 50 years, hyperthermia-based cancer researchers have utilized mathematical models, cell culture studies and animal models to better understand, develop and validate potential new treatments. It has been, and remains, unclear how and to what degree these research techniques depend on, complement and, ultimately, translate accurately to a successful clinical treatment. In the past, when mathematical models have not proven accurate in a clinical treatment situation, the initiating quantitative scientists (engineers, mathematicians and physicists) have tended to believe the biomedical parameters provided to them were inaccurately determined or reported. In a similar manner, experienced biomedical scientists often tend to question the value of mathematical models and cell culture results since those data typically lack the level of biologic and medical variability and complexity that are essential to accurately study and predict complex diseases and subsequent treatments. Such quantitative and biomedical interdependence, variability, diversity and promise have never been greater than they are within magnetic nanoparticle hyperthermia cancer treatment. The use of hyperthermia to treat cancer is well studied and has utilized numerous delivery techniques, including microwaves, radio frequency, focused ultrasound, induction heating, infrared radiation, warmed perfusion liquids (combined with chemotherapy), and, recently, metallic nanoparticles (NP) activated by near infrared radiation (NIR) and alternating magnetic field (AMF) based platforms. The goal of this paper is to use proven concepts and current research to address the potential pathobiology, modeling and quantification of the effects of treatment as pertaining to the similarities and differences in energy delivered by known external delivery techniques and iron oxide nanoparticles.

  19. Regional hyperthermia of the liver

    International Nuclear Information System (INIS)

    Petrovich, Z.; Langholz, B.; Astrahan, M.; Emami, B.; Oleson, J.R.

    1989-01-01

    From 1981 through 1986, 49 patients with metastatic liver tumors received deep regional hyperthermia in phase I protocols in six major medical centers in the United States. Adenocarcinoma was seen in 80% of patients with colon as the primary site in 26%. The remaining patients had the following histological diagnoses: Soft tissue sarcoma in seven, malignant melanoma in two and transitional cell carcinoma in one. Deep regional hyperthermia treatments with a BSD-1000 annular phased array were given once or twice a week with a total of 167 treatment sessions, mean 3.4 (range 1 to 8). In addition to deep regional hyperthermia, 17 patients received radiotherapy, and 14 received chemotherapy. The median survival for all patients was 25 weeks. Complete response was obtained in two patients and partial response in four patients. An additional ten patients had nominal response. There was no complete or partial response among the 14 hyperthermia alone treated patients. Of the 26 patients who presented with severe pain, five had complete pain relief, five had partial relief and the majority had a lesser degree of pain relief or no pain relief. Acute treatment toxicity consisted of pain in ten, systemic temperature increase to 39 0 C in four tachycardia in two, claustrophobia in one. The majority of patients did not experience acute toxicity. No late toxicity was recorded in this group of 49 patients. (orig./MG)

  20. The correlation between the rise of the tumor temperature during the hyperthermia treatment and the tumor blood flow measured by dynamic CT and 15O gas-positron emission tomography

    International Nuclear Information System (INIS)

    Hattori, Hideyuki

    1993-01-01

    This study was designed to determine the correlation between the rise of tumor temperature during hyperthermia treatment and the blood flow of the tumors measured by dynamic CT (DCT) and 15 O gas-positron emission tomography. In this report, we observed 20 patients with malignant tumors which underwent hyperthermia treatment. In each case, the temperature of the tumor was monitored with a photofiber sensor. DCT's and 15 O gas-positron emission tomographies were applied before the hyperthermia treatment. During the DCT, the tumor blood flow of each tumor was estimated by analyzing the time-dependent activity curve after a bolus injection. During the 15 O gas-positron emission tomography, the tumor blood flow was estimated by the C 15 O 2 -steady-state method. The value of the tumor blood flow estimated by DCT were proportional to those calculated by the 15 O gas-positron emission tomography. These values were inversely proportional to the rise of the temperature of the tumors during hyperthermia treatment. Our results imply that DCT as well as the 15 O gas-positron emission tomography can be used for the prediction of the tumor temperature rise during the hyperthermia treatment. (author)

  1. An overview of interstitial brachytherapy and hyperthermia

    International Nuclear Information System (INIS)

    Brandt, B.B.; Harney, J.

    1989-01-01

    Interstitial thermoradiotherapy, an experimental cancer treatment that combines interstitial radiation implants (brachytherapy) and interstitial hyperthermia, is in the early stages of investigation. In accordance with the procedure used in a current national trial protocol, a 60-minute hyperthermia treatment is administered after catheters are placed into the tumor area while the patient is under general anesthesia. This is immediately followed by loading of radioactive Iridium-192 seeds into the catheters for a defined period of time. Once the prescribed radiation dose is delivered, the radioactive sources are removed and a second, 60-minute hyperthermia treatment is administered. Clinical trials with hyperthermia in combination with radiation have increased in recent years. Nurses caring for these patients need to become more knowledgeable about this investigational therapy. This paper provides an overview of the biologic rationale for this therapy, as well as a description of the delivery method and clinical application. Specific related nursing interventions are defined in a nursing protocol.23 references

  2. Feasibility study on 3D image reconstruction from 2D orthogonal cine-MRI for MRI-guided radiotherapy.

    Science.gov (United States)

    Paganelli, Chiara; Lee, Danny; Kipritidis, John; Whelan, Brendan; Greer, Peter B; Baroni, Guido; Riboldi, Marco; Keall, Paul

    2018-02-11

    In-room MRI is a promising image guidance strategy in external beam radiotherapy to acquire volumetric information for moving targets. However, limitations in spatio-temporal resolution led several authors to use 2D orthogonal images for guidance. The aim of this work is to present a method to concurrently compensate for non-rigid tumour motion and provide an approach for 3D reconstruction from 2D orthogonal cine-MRI slices for MRI-guided treatments. Free-breathing sagittal/coronal interleaved 2D cine-MRI were acquired in addition to a pre-treatment 3D volume in two patients. We performed deformable image registration (DIR) between cine-MRI slices and corresponding slices in the pre-treatment 3D volume. Based on an extrapolation of the interleaved 2D motion fields, the 3D motion field was estimated and used to warp the pre-treatment volume. Due to the lack of a ground truth for patients, the method was validated on a digital 4D lung phantom. On the phantom, the 3D reconstruction method was able to compensate for tumour motion and compared favourably to the results of previously adopted strategies. The difference in the 3D motion fields between the phantom and the extrapolated motion was 0.4 ± 0.3 mm for tumour and 0.8 ± 1.5 mm for whole anatomy, demonstrating feasibility of performing a 3D volumetric reconstruction directly from 2D orthogonal cine-MRI slices. Application of the method to patient data confirmed the feasibility of utilizing this method in real world scenarios. Preliminary results on phantom and patient cases confirm the feasibility of the proposed approach in an MRI-guided scenario, especially for non-rigid tumour motion compensation. © 2018 The Royal Australian and New Zealand College of Radiologists.

  3. Towards MRI-guided linear accelerator control: gating on an MRI accelerator.

    Science.gov (United States)

    Crijns, S P M; Kok, J G M; Lagendijk, J J W; Raaymakers, B W

    2011-08-07

    , we will realize more intricate MRI-guided linear accelerator control in the near future.

  4. Hyperthermia and chemotherapy agent

    International Nuclear Information System (INIS)

    Roizin-Towle, L.; Hall, E.J.

    1981-01-01

    The use of chemotherapeutic agents for the treatment of cancer dates back to the late 19th century, but the modern era of chemotherapy drugs was ushered in during the 1940's with the development of the polyfunctional alkylating agent. Since then, numerous classes of drugs have evolved and the combined use of antineoplastic agents with other treatment modalities such as radiation or heat, remains a large relatively unexplored area. This approach, combining local hyperthermia with chemotherapy agents affords a measure of targeting and selective toxicity not previously available for drugs. In this paper, the effects of adriamycin, bleomycin and cis-platinum are examined. The adjuvant use of heat may also reverse the resistance of hypoxic cells noted for some chemotherapy agents

  5. Individualised 3D printed vaginal template for MRI guided brachytherapy in locally advanced cervical cancer

    DEFF Research Database (Denmark)

    Lindegaard, Jacob Christian; Lænsø Madsen, Mads; Hansen, Anders Traberg

    2016-01-01

    Intracavitary–interstitial applicators for MRI guided brachytherapy are becoming increasingly important in locally advanced cervical cancer. The 3D printing technology enables a versatile method for obtaining a high degree of individualisation of the implant. Our clinical workflow is presented...

  6. Saline as the Sole Contrast Agent for Successful MRI-guided Epidural Injections

    International Nuclear Information System (INIS)

    Deli, Martin; Fritz, Jan; Mateiescu, Serban; Busch, Martin; Carrino, John A.; Becker, Jan; Garmer, Marietta; Grönemeyer, Dietrich

    2013-01-01

    Purpose. To assess the performance of sterile saline solution as the sole contrast agent for percutaneous magnetic resonance imaging (MRI)-guided epidural injections at 1.5 T. Methods. A retrospective analysis of two different techniques of MRI-guided epidural injections was performed with either gadolinium-enhanced saline solution or sterile saline solution for documentation of the epidural location of the needle tip. T1-weighted spoiled gradient echo (FLASH) images or T2-weighted single-shot turbo spin echo (HASTE) images visualized the test injectants. Methods were compared by technical success rate, image quality, table time, and rate of complications. Results. 105 MRI-guided epidural injections (12 of 105 with gadolinium-enhanced saline solution and 93 of 105 with sterile saline solution) were performed successfully and without complications. Visualization of sterile saline solution and gadolinium-enhanced saline solution was sufficient, good, or excellent in all 105 interventions. For either test injectant, quantitative image analysis demonstrated comparable high contrast-to-noise ratios of test injectants to adjacent body substances with reliable statistical significance levels (p < 0.001). The mean table time was 22 ± 9 min in the gadolinium-enhanced saline solution group and 22 ± 8 min in the saline solution group (p = 0.75). Conclusion. Sterile saline is suitable as the sole contrast agent for successful and safe percutaneous MRI-guided epidural drug delivery at 1.5 T.

  7. MRI-guided percutaneous retrograde drilling of osteochondritis dissecans of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Ojala, Risto; Kerimaa, Pekka; Tervonen, Osmo; Blanco-Sequeiros, Roberto [Oulu University Hospital, Department of Radiology, Oulu (Finland); Lakovaara, Martti [Oulu Deaconess Institute, Department of Surgery, Oulu (Finland); Hyvoenen, Pekka; Lehenkari, Petri [Oulu University Hospital, Department of Surgery, Oulu (Finland)

    2011-06-15

    The purpose of this study was to evaluate the feasibility of a new method for osteochondritis dissecans (OCD) treatment. Ten OCD lesions of the knee unresponsive to conservative management were treated with MRI-guided percutaneous retrograde drilling to reduce symptoms and promote ossification of the lesion. All lesions were located in distal femoral condyles. Only stable OCD lesions were included (preprocedural MRI grade I or II). Five lesions were of juvenile type and five lesions were of adult type OCD. All the patients had severe limitation of activity due to the OCD-related pain. By using a 0.23 T open MRI scanner and spinal anesthesia, percutaneous retrograde drilling of the OCD lesions was performed (3 mm cylindrical drill, one to three channels). Optical tracking and MRI imaging were used to guide instruments during the procedure. Mean postprocedural clinical follow-up time was 3 years. Eight patients had a post-procedural follow-up MRI within 1 year. All the OCD lesions were located and drilled using the 0.23 T open MRI scanner without procedural complications. All the patients had pain relief, mean visual analog score (VAS) declined from 6 to 2. Follow-up MRI showed ossification in all lesions. Eight patients could return to normal physical activity with no or minor effect on function (Hughston score 3-4). Treatment failed in two cases where the continuation of symptoms led to arthroscopy and transchondral fixation. MR-guided retrograde OCD lesion drilling is an accurate, feasible, and effective cartilage-sparing techique in OCD management. (orig.)

  8. MRI-guided percutaneous retrograde drilling of osteochondritis dissecans of the knee

    International Nuclear Information System (INIS)

    Ojala, Risto; Kerimaa, Pekka; Tervonen, Osmo; Blanco-Sequeiros, Roberto; Lakovaara, Martti; Hyvoenen, Pekka; Lehenkari, Petri

    2011-01-01

    The purpose of this study was to evaluate the feasibility of a new method for osteochondritis dissecans (OCD) treatment. Ten OCD lesions of the knee unresponsive to conservative management were treated with MRI-guided percutaneous retrograde drilling to reduce symptoms and promote ossification of the lesion. All lesions were located in distal femoral condyles. Only stable OCD lesions were included (preprocedural MRI grade I or II). Five lesions were of juvenile type and five lesions were of adult type OCD. All the patients had severe limitation of activity due to the OCD-related pain. By using a 0.23 T open MRI scanner and spinal anesthesia, percutaneous retrograde drilling of the OCD lesions was performed (3 mm cylindrical drill, one to three channels). Optical tracking and MRI imaging were used to guide instruments during the procedure. Mean postprocedural clinical follow-up time was 3 years. Eight patients had a post-procedural follow-up MRI within 1 year. All the OCD lesions were located and drilled using the 0.23 T open MRI scanner without procedural complications. All the patients had pain relief, mean visual analog score (VAS) declined from 6 to 2. Follow-up MRI showed ossification in all lesions. Eight patients could return to normal physical activity with no or minor effect on function (Hughston score 3-4). Treatment failed in two cases where the continuation of symptoms led to arthroscopy and transchondral fixation. MR-guided retrograde OCD lesion drilling is an accurate, feasible, and effective cartilage-sparing techique in OCD management. (orig.)

  9. Hyperthermia generated by Foucault currents for oncological treatments with COMSOL; Hipertermia generada por corrientes Foucault para tratamientos oncologicos con COMSOL

    Energy Technology Data Exchange (ETDEWEB)

    Romero C, R. L.; Cordova F, T.; Basurto I, G. [Universidad de Guanajuato, Campus Leon, Departamento de Ingenieria Fisica, Loma del Bosque 103, Lomas del Campestre, 37150 Leon, Guanajuato (Mexico); Guzman C, R. [Universidad de Guanajuato, Campus Irapuato-Salamanca, Division de Ingenierias, Carretera Salamanca-Valle de Santiago Km 3.5, Comunidad de Palo Blanco, 36885 Salamanca, Guanajuato (Mexico); Castro L, J., E-mail: rosariolrc@gmail.com [Universidad del Mar, Campus Puerto Angel, Carretera a Zipolite Km 1.5, Col. Puerto Angel, 70902 San Pedro Pochutla, Oaxaca (Mexico)

    2017-10-15

    The hyperthermia generated by variable magnetic fields is a promising power method for oncological therapy, because apoptosis is induced in tumor cells at temperatures between 42 and 45 degrees Celsius. It is known that an alternating magnetic field on the FeO{sub 4} magnetite particles produces heat through three paths: is generated by parasitic currents, lost in hysteresis cycles and losses by magnetization relaxation; taking advantage of the energy losses through the joule effect and the transformation into heat, a simulation is shown in COMSOL about the temporal distribution of temperature in transformed biological systems, to have an estimate of the properties and behavior of the temperature gradient when magnetic hyperthermia is generated in human transformed tissue. (Author)

  10. A flexible 70 MHz phase-controlled double waveguide system for hyperthermia treatment of superficial tumours with deep infiltration.

    Science.gov (United States)

    van Stam, Gerard; Kok, H Petra; Hulshof, Maarten C C M; Kolff, M Willemijn; van Tienhoven, Geertjan; Sijbrands, Jan; Bakker, Akke; Zum Vörde Sive Vörding, Paul J; Oldenborg, Sabine; de Greef, Martijn; Rasch, Coen R N; Crezee, Hans

    2017-11-01

    Superficial tumours with deep infiltration in the upper 15 cm of the trunk cannot be treated adequately with existing hyperthermia systems. The aim of this study was to develop, characterise and evaluate a new flexible two-channel hyperthermia system (AMC-2) for tumours in this region. The two-channel AMC-2 system has two horizontally revolving and height adjustable 70 MHz waveguides. Three different interchangeable antennas with sizes 20 × 34, 15 × 34 and 8.5 × 34 cm were developed and their electrical properties were determined. The performance of the AMC-2 system was tested by measurements of the electric field distribution in a saline water filled elliptical phantom, using an electric field vector probe. Clinical feasibility was demonstrated by treatment of a melanoma in the axillary region. Phantom measurements showed a good performance for all waveguides. The large reflection of the smallest antenna has to be compensated by increased forward power. Field patterns become asymmetrical when using smaller top antennas, necessitating phase corrections. The clinical application showed that tumours deeper than 4 cm can be heated adequately. A median tumour temperature of 42 °C can be reached up to 12 cm depth with adequate antenna positioning and phase-amplitude steering. This 70 MHz AMC-2 waveguide system is a useful addition to existing loco-regional hyperthermia equipment as it is capable of heating axillary tumours and other tumours deeper than 4 cm.

  11. SU-E-J-201: Investigation of MRI Guided Proton Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Li, JS [Fox Chase Cancer Center, Philadelphia, PA (United States)

    2015-06-15

    Purpose: Image-guided radiation therapy has been employed for cancer treatment to improve the tumor localization accuracy. Radiation therapy with proton beams requires more on this accuracy because the proton beam has larger uncertainty and dramatic dose variation along the beam direction. Among all the image modalities, magnetic-resonance image (MRI) is the best for soft tissue delineation and real time motion monitoring. In this work, we investigated the behavior of the proton beam in magnetic field with Monte Carlo simulations. Methods: A proton Monte Carlo platform, TOPAS, was used for this investigation. Dose calculations were performed with this platform in a 30cmx30cmx30cm water phantom for both pencil and broad proton beams with different energies (120, 150 and 180MeV) in different magnetic fields (0.5T, 1T and 3T). The isodose distributions, dose profiles in lateral and beam direction were evaluated. The shifts of the Bragg peak in different magnetic fields for different proton energies were compared and the magnetic field effects on the characters of the dose distribution were analyzed. Results: Significant effects of magnetic field have been observed on the proton beam dose distributions, especially for magnetic field of 1T and up. The effects are more significant for higher energy proton beam because higher energy protons travel longer distance in the magnetic field. The Bragg peak shift in the lateral direction is about 38mm for 180MeV and 11mm for 120MeV proton beams in 3T magnetic field. The peak positions are retracted back for 6mm and 2mm, respectively. The effect on the beam penumbra and dose falloff at the distal edge of the Bragg peak is negligible. Conclusion: Though significant magnetic effects on dose distribution have been observed for proton beams, MRI guided proton therapy is feasible because the magnetic effects on dose is predictable and can be considered in patient dose calculation.

  12. pH- and NIR Light-Responsive Polymeric Prodrug Micelles for Hyperthermia-Assisted Site-Specific Chemotherapy to Reverse Drug Resistance in Cancer Treatment.

    Science.gov (United States)

    Li, Zuhong; Wang, Haibo; Chen, Yangjun; Wang, Yin; Li, Huan; Han, Haijie; Chen, Tingting; Jin, Qiao; Ji, Jian

    2016-05-01

    Despite the exciting advances in cancer chemotherapy over past decades, drug resistance in cancer treatment remains one of the primary reasons for therapeutic failure. IR-780 loaded pH-responsive polymeric prodrug micelles with near infrared (NIR) photothermal effect are developed to circumvent the drug resistance in cancer treatment. The polymeric prodrug micelles are stable in physiological environment, while exhibit fast doxorubicin (DOX) release in acidic condition and significant temperature elevation under NIR laser irradiation. Phosphorylcholine-based biomimetic micellar shell and acid-sensitive drug conjugation endow them with prolonged circulation time and reduced premature drug release during circulation to conduct tumor site-specific chemotherapy. The polymeric prodrug micelles combined with NIR laser irradiation could significantly enhance intracellular DOX accumulation and synergistically induce the cell apoptosis in DOX-resistant MCF-7/ADR cells. Meanwhile, the tumor site-specific chemotherapy combined with hyperthermia effect induces significant inhibition of MCF-7/ADR tumor growth in tumor-bearing mice. These results demonstrate that the well-designed IR-780 loaded polymeric prodrug micelles for hyperthermia-assisted site-specific chemotherapy present an effective approach to reverse drug resistance. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Malignant hyperthermia

    Science.gov (United States)

    ... linked with the disease Muscle biopsy Urine myoglobin (muscle protein) Treatment During an episode of MH, a medicine called ... Fluid buildup in the lungs Weak or deformed muscles (myopathy or muscular dystrophy ) When to Contact a Medical Professional If you ...

  14. Physical characteristics cannot be used to predict cooling time using cold-water immersion as a treatment for exertional hyperthermia.

    Science.gov (United States)

    Poirier, Martin P; Notley, Sean R; Flouris, Andreas D; Kenny, Glen P

    2018-03-12

    We examined if physical characteristics could be used to predict cooling time during cold water immersion (CWI, 2°C) following exertional hyperthermia (rectal temperature ≥39.5°C) in a physically heterogeneous group of men and women (n=62). Lean body mass was the only significant predictor of cooling time following CWI (R2=0.137; P<0.001); however that prediction did not provide the precision (mean residual square error: 3.18±2.28 min) required to act as a safe alternative to rectal temperature measurements.

  15. Study on brain hemodynamics function according to data of rheoencephalography during multimodality treatment of oncologic patients with the use of general controlled artificial hyperthermia with hyperglycemia or with large insulin doses

    International Nuclear Information System (INIS)

    Lysenko, E.V.

    1990-01-01

    For the first time the effect of single and multiple treatments of artificial hyperthermia (AHT) with hyperglycemia (HG) or with large insulin doses on cerebral circulation of oncologic patients is studied. Cerebral hemodynamics was studied by rheoencephalography. The conclusion is made about the unidirectional AHT effect regardless of the bacrground used. 5 refs.; 4 tabs

  16. Fast MRI-guided vacuum-assisted breast biopsy: initial experience.

    Science.gov (United States)

    Liberman, Laura; Morris, Elizabeth A; Dershaw, D David; Thornton, Cynthia M; Van Zee, Kimberly J; Tan, Lee K

    2003-11-01

    The purpose of this study was to evaluate a new method for performing MRI-guided vacuum-assisted breast biopsy in a study of lesions that had subsequent surgical excision. SUBJECTS AND METHODS. Twenty women scheduled for MRI-guided needle localization and surgical biopsy were prospectively entered in the study. MRI-guided biopsy was performed with a vacuum-assisted probe, followed by placement of a localizing clip, and then needle localization for surgical excision. Vacuum-assisted biopsy and surgical histology were correlated. Vacuum-assisted biopsy was successfully performed in 19 (95%) of the 20 women. The median size of 27 MRI-detected lesions that had biopsy was 1.0 cm (range, 0.4-6.4 cm). Cancer was present in eight (30%) of 27 lesions and in six (32%) of 19 women; among these eight cancers, five were infiltrating and three were ductal carcinoma in situ (DCIS). Among these 27 lesions, histology was benign at vacuum-assisted biopsy and at surgery in 19 (70%), cancer at vacuum-assisted biopsy in six (22%), atypical ductal hyperplasia at vacuum-assisted biopsy and DCIS at surgery in one (4%), and benign at vacuum-assisted biopsy with surgery showing microscopic DCIS that was occult at MRI in one (4%). The median time to perform vacuum-assisted biopsy of a single lesion was 35 min (mean, 35 min; range, 24-48 min). Placement of a localizing clip, attempted in 26 lesions, was successful in 25 (96%) of 26, and the clip was retrieved on specimen radiography in 22 (96%) of 23. One complication occurred: a hematoma that resolved with compression. MRI-guided vacuum-assisted biopsy is a fast, safe, and accurate alternative to surgical biopsy for breast lesions detected on MRI.

  17. Piezoelectrically Actuated Robotic System for MRI-Guided Prostate Percutaneous Therapy

    OpenAIRE

    Su, Hao; Shang, Weijian; Cole, Gregory; Li, Gang; Harrington, Kevin; Camilo, Alexander; Tokuda, Junichi; Tempany, Clare M.; Hata, Nobuhiko; Fischer, Gregory S.

    2014-01-01

    This paper presents a fully-actuated robotic system for percutaneous prostate therapy under continuously acquired live magnetic resonance imaging (MRI) guidance. The system is composed of modular hardware and software to support the surgical workflow of intra-operative MRI-guided surgical procedures. We present the development of a 6-degree-of-freedom (DOF) needle placement robot for transperineal prostate interventions. The robot consists of a 3-DOF needle driver module and a 3-DOF Cartesian...

  18. A Concentric Tube Continuum Robot with Piezoelectric Actuation for MRI-Guided Closed-Loop Targeting

    OpenAIRE

    Su, Hao; Li, Gang; Rucker, D. Caleb; Webster, Robert J.; Fischer, Gregory S.

    2016-01-01

    This paper presents the design, modeling and experimental evaluation of a magnetic resonance imaging (MRI)-compatible concentric tube continuum robotic system. This system enables MRI-guided deployment of a precurved and steerable concentric tube continuum mechanism, and is suitable for clinical applications where a curved trajectory is needed. This compact 6 degree-of-freedom (DOF) robotic system is piezoelectrically-actuated, and allows simultaneous robot motion and imaging with no visually...

  19. MRI-guided stereotactic neurosurgical procedures in a diagnostic MRI suite: Background and safe practice recommendations.

    Science.gov (United States)

    Larson, Paul S; Willie, Jon T; Vadivelu, Sudhakar; Azmi-Ghadimi, Hooman; Nichols, Amy; Fauerbach, Loretta Litz; Johnson, Helen Boehm; Graham, Denise

    2017-07-01

    The development of navigation technology facilitating MRI-guided stereotactic neurosurgery has enabled neurosurgeons to perform a variety of procedures ranging from deep brain stimulation to laser ablation entirely within an intraoperative or diagnostic MRI suite while having real-time visualization of brain anatomy. Prior to this technology, some of these procedures required multisite workflow patterns that presented significant risk to the patient during transport. For those facilities with access to this technology, safe practice guidelines exist only for procedures performed within an intraoperative MRI. There are currently no safe practice guidelines or parameters available for facilities looking to integrate this technology into practice in conventional MRI suites. Performing neurosurgical procedures in a diagnostic MRI suite does require precautionary measures. The relative novelty of technology and workflows for direct MRI-guided procedures requires consideration of safe practice recommendations, including those pertaining to infection control and magnet safety issues. This article proposes a framework of safe practice recommendations designed for assessing readiness and optimization of MRI-guided neurosurgical interventions in the diagnostic MRI suite in an effort to mitigate patient risk. The framework is based on existing clinical evidence, recommendations, and guidelines related to infection control and prevention, health care-associated infections, and magnet safety, as well as the clinical and practical experience of neurosurgeons utilizing this technology. © 2017 American Society for Healthcare Risk Management of the American Hospital Association.

  20. A Concentric Tube Continuum Robot with Piezoelectric Actuation for MRI-Guided Closed-Loop Targeting

    Science.gov (United States)

    Su, Hao; Li, Gang; Rucker, D. Caleb; Webster, Robert J.; Fischer, Gregory S.

    2017-01-01

    This paper presents the design, modeling and experimental evaluation of a magnetic resonance imaging (MRI)-compatible concentric tube continuum robotic system. This system enables MRI-guided deployment of a precurved and steerable concentric tube continuum mechanism, and is suitable for clinical applications where a curved trajectory is needed. This compact 6 degree-of-freedom (DOF) robotic system is piezoelectrically-actuated, and allows simultaneous robot motion and imaging with no visually observable image artifact. The targeting accuracy is evaluated with optical tracking system and gelatin phantom under live MRI-guidance with Root Mean Square (RMS) errors of 1.94 and 2.17 mm respectively. Furthermore, we demonstrate that the robot has kinematic redundancy to reach the same target through different paths. This was evaluated in both free space and MRI-guided gelatin phantom trails, with RMS errors of 0.48 and 0.59 mm respectively. As the first of its kind, MRI-guided targeted concentric tube needle placements with ex vivo porcine liver are demonstrated with 4.64 mm RMS error through closed-loop control of the piezoelectrically-actuated robot. PMID:26983842

  1. MRI-guided robot for needle interventions in the prostate

    NARCIS (Netherlands)

    van den Bosch, M.R.

    2011-01-01

    Magnetic resonance imaging (MRI) is applied to non-invasively visualize patient’s anatomy and tumour suspicious regions with superior soft tissue contrast. Amongst others, online MRI is valuable in the diagnostic and treatment techniques for prostate cancer. Clinical MR scanners are suitable to

  2. A robotic device for MRI-guided prostate brachytherapy

    NARCIS (Netherlands)

    Lagerburg, V.

    2008-01-01

    One of the treatment options for prostate cancer is brachytherapy with iodine-125 sources. In prostate brachytherapy a high radiation dose is delivered to the prostate with a steep dose fall off to critical surrounding organs. The implantation of the iodine sources is currently performed under

  3. MRI-guided brachytherapy for cancer of the oesophagus

    International Nuclear Information System (INIS)

    Aydin, H.; Bachmann, G.; Lieven, H. von; Sens, M.

    1993-01-01

    A method of brachytherapy treatment planning using MRI is presented. In 13 patients with inoperable squamous cell cancer of the thoracic oesophagus an intraluminal afterloading boost with MRI assistance was performed. A new type of flexible catheter was filled with 1/100 diluted Gd-DTPA and introduced into the oesophagus before performing MRI in the sagittal, coronal and transverse planes. One sagittal or coronal picture which showed the catheter tip and the residual cancer was magnified to ''life size''. The position of the catheter was corrected if necessary and the treatment volume decided. The contrast medium was then aspirated out of the catheter and a thinner afterloading catheter pushed into the outer catheter. The patient was moved immediately to the afterloading room and received the first dose of boost irradiation. This method allows much more precise brachytherapy planning since it shows the cancer and the catheter together. It is superior to localising the cancer with a barium swallow or endoscopy because MRI visualises the whole extent of the residual cancer, which can then be covered with the necessary dose. (orig.)

  4. Combined treatment of radiotherapy and local hyperthermia using 8 MHz RF-wave for advanced carcinoma of the breast

    Energy Technology Data Exchange (ETDEWEB)

    Fuwa, Nobukazu

    1988-01-01

    During the period from January 1983 through September 1986, 13 patients with carcinoma of the breast were treated with local hyperthermia combined with radiotherapy. Six patients were inoperable advanced cases and the other 7 were recurrent cases. Local heat was applied with an 8-MHz RF-capacitive heating equipment, once or twice a week after radiotherapy, for 40 approx. 60 minutes per session. Of the 6 cases with inoperable advanced lesions, 4 achieved CR and the other 2 achieved PRa (80 approx. 100 % regression), and of the 7 cases with local recurrent tumors, 3 achieved CR and the other 4 achieved PRa. As complications of the thermoradiotherapy, grade I-II skin burns were observed in 9 cases, pain around the ribs in 8 cases, mild lassitude in 2 cases, persistent tachycardia in 1 case and acute erosive gastritis in 1 case. It is worth noting that CR was achieved in these huge tumors, which can not be controlled by radiotherapy alone.

  5. MRI-guided stereotactic amygdalohippocampectomy: a single center experience

    Directory of Open Access Journals (Sweden)

    Vojtěch Z

    2015-02-01

    Full Text Available Zdenek Vojtěch,1 Hana Malíková,2 Lenka Krámská,3 Roman Liščák,4 Vilibald Vladyka41Department of Neurology, 2Department of Radiodiagnostics, 3Department of Psychology, 4Department of Stereotactic and Radiation Neurosurgery, Na Homolce Hospital, Prague, Czech RepublicBackground: This paper presents our experience of stereotactic radiofrequency amygdalohippocampectomy performed for intractable mesial temporal lobe epilepsy.Methods: The article describes the cases of 61 patients who were treated during the period from 2004 to 2010. Mean postoperative follow-up was 5.3 years. Neuropsychological results were obtained for a subset of 31 patients.Results: At their last postsurgical visit, 43 (70.5% patients were Engel class I, six (9.8% class II, nine (14.8% class III, and three (4.9% class IV. The surgery was complicated by four intracranial hematomas. One of them caused acute hydrocephalus and was treated by shunting and resolved without sequelae, while another caused transitory aphasia. The remaining hematomas were asymptomatic. There were two cases of meningitis which required antibiotic treatment. One patient committed suicide due to postoperative depression. After the procedure, we performed open epilepsy surgery and rethermolesions in three and two patients, respectively (8.2%. Patients showed increases in their mean full scale, verbal, and performance intelligence quotient (IQ scores of 4, 3, and 4 IQ points, respectively (P<0.05. Five (17.2%, four (13.8%, and four (13.3% patients improved their full scale, verbal, and performance IQ scores, respectively. No significant changes were found in memory performance, with a mean increase of 1, 3, and 0 memory quotient points in global, verbal, and visual memory, respectively (P<0.05. Global memory improved in three (10.3% patients, verbal memory in one (3.4%, and one patient (3.3% showed deterioration in visual memory.Conclusion: Stereotactic radiofrequency amygdalohippocampectomy offers a

  6. Ultrasonic system for hyperthermia

    International Nuclear Information System (INIS)

    Seppi, E.J.; Shapiro, E.G.; Zitelli, L.T.

    1985-01-01

    A system using ultrasound has been developed for hyperthermia application. It consists of a water bed containing a large ultrasound transducer array for heat application, an annular imaging transducer for alignment and treatment monitoring, and a 30-channel monitoring system for invasive temperature measurements. The heat applicator array contains 30 transducers mounted in a hexagonal configuration. Four subsets of transducers in the array can be remotely mechanically driven in such a way as to allow control of the distribution and diameter of ultrasound power at the effective focus of the array. The array can be remotely translated in three dimensions and can be rotated about its axis of symmetry. These motions allow positioning of the focal area of the array at the desired location. Each transducer of the array is powered by an individual amplifier and can be controlled in intensity and phase. The system can operate at variable ultrasound frequencies. An imaging transducer located at the center of the heat applicator array is used to collect data for ultrasound imaging and other purposes. Ultrasound images are displayed along with marks indicating the location of the heat applicator focal region for setup and for monitoring during treatment. The entire system is under computer control. This allows for operator ease in the control of the numerous parameters involved in the operation of the system

  7. MRI-guided tumor tracking in lung cancer radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Cervino, Laura I; Jiang, Steve B [Center for Advanced Radiotherapy Technology and Department of Radiation Oncology, University of California San Diego, 3960 Health Sciences Dr., La Jolla, CA 92093-0865 (United States); Du, Jiang, E-mail: lcervino@ucsd.edu [Department of Radiology, University of California San Diego, 200 West Arbor Dr., San Diego, CA 92103-8226 (United States)

    2011-07-07

    Precise tracking of lung tumor motion during treatment delivery still represents a challenge in radiation therapy. Prototypes of MRI-linac hybrid systems are being created which have the potential of ionization-free real-time imaging of the tumor. This study evaluates the performance of lung tumor tracking algorithms in cine-MRI sagittal images from five healthy volunteers. Visible vascular structures were used as targets. Volunteers performed several series of regular and irregular breathing. Two tracking algorithms were implemented and evaluated: a template matching (TM) algorithm in combination with surrogate tracking using the diaphragm (surrogate was used when the maximum correlation between the template and the image in the search window was less than specified), and an artificial neural network (ANN) model based on the principal components of a region of interest that encompasses the target motion. The mean tracking error e and the error at 95% confidence level e{sub 95} were evaluated for each model. The ANN model led to e = 1.5 mm and e{sub 95} = 4.2 mm, while TM led to e = 0.6 mm and e{sub 95} = 1.0 mm. An extra series was considered separately to evaluate the benefit of using surrogate tracking in combination with TM when target out-of-plane motion occurs. For this series, the mean error was 7.2 mm using only TM and 1.7 mm when the surrogate was used in combination with TM. Results show that, as opposed to tracking with other imaging modalities, ANN does not perform well in MR-guided tracking. TM, however, leads to highly accurate tracking. Out-of-plane motion could be addressed by surrogate tracking using the diaphragm, which can be easily identified in the images.

  8. TH-AB-BRA-02: Automated Triplet Beam Orientation Optimization for MRI-Guided Co-60 Radiotherapy

    International Nuclear Information System (INIS)

    Nguyen, D; Thomas, D; Cao, M; O’Connor, D; Lamb, J; Sheng, K

    2016-01-01

    Purpose: MRI guided Co-60 provides daily and intrafractional MRI soft tissue imaging for improved target tracking and adaptive radiotherapy. To remedy the low output limitation, the system uses three Co-60 sources at 120° apart, but using all three sources in planning is considerably unintuitive. We automate the beam orientation optimization using column generation, and then solve a novel fluence map optimization (FMO) problem while regularizing the number of MLC segments. Methods: Three patients—1 prostate (PRT), 1 lung (LNG), and 1 head-and-neck boost plan (H&NBoost)—were evaluated. The beamlet dose for 180 equally spaced coplanar beams under 0.35 T magnetic field was calculated using Monte Carlo. The 60 triplets were selected utilizing the column generation algorithm. The FMO problem was formulated using an L2-norm minimization with anisotropic total variation (TV) regularization term, which allows for control over the number of MLC segments. Our Fluence Regularized and Optimized Selection of Triplets (FROST) plans were compared against the clinical treatment plans (CLN) produced by an experienced dosimetrist. Results: The mean PTV D95, D98, and D99 differ by −0.02%, +0.12%, and +0.44% of the prescription dose between planning methods, showing same PTV dose coverage. The mean PTV homogeneity (D95/D5) was at 0.9360 (FROST) and 0.9356 (CLN). R50 decreased by 0.07 with FROST. On average, FROST reduced Dmax and Dmean of OARs by 6.56% and 5.86% of the prescription dose. The manual CLN planning required iterative trial and error runs which is very time consuming, while FROST required minimal human intervention. Conclusions: MRI guided Co-60 therapy needs the output of all sources yet suffers from unintuitive and laborious manual beam selection processes. Automated triplet orientation optimization is shown essential to overcome the difficulty and improves the dosimetry. A novel FMO with regularization provides additional controls over the number of MLC segments

  9. TH-AB-BRA-02: Automated Triplet Beam Orientation Optimization for MRI-Guided Co-60 Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, D; Thomas, D; Cao, M; O’Connor, D; Lamb, J; Sheng, K [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA (United States)

    2016-06-15

    Purpose: MRI guided Co-60 provides daily and intrafractional MRI soft tissue imaging for improved target tracking and adaptive radiotherapy. To remedy the low output limitation, the system uses three Co-60 sources at 120° apart, but using all three sources in planning is considerably unintuitive. We automate the beam orientation optimization using column generation, and then solve a novel fluence map optimization (FMO) problem while regularizing the number of MLC segments. Methods: Three patients—1 prostate (PRT), 1 lung (LNG), and 1 head-and-neck boost plan (H&NBoost)—were evaluated. The beamlet dose for 180 equally spaced coplanar beams under 0.35 T magnetic field was calculated using Monte Carlo. The 60 triplets were selected utilizing the column generation algorithm. The FMO problem was formulated using an L2-norm minimization with anisotropic total variation (TV) regularization term, which allows for control over the number of MLC segments. Our Fluence Regularized and Optimized Selection of Triplets (FROST) plans were compared against the clinical treatment plans (CLN) produced by an experienced dosimetrist. Results: The mean PTV D95, D98, and D99 differ by −0.02%, +0.12%, and +0.44% of the prescription dose between planning methods, showing same PTV dose coverage. The mean PTV homogeneity (D95/D5) was at 0.9360 (FROST) and 0.9356 (CLN). R50 decreased by 0.07 with FROST. On average, FROST reduced Dmax and Dmean of OARs by 6.56% and 5.86% of the prescription dose. The manual CLN planning required iterative trial and error runs which is very time consuming, while FROST required minimal human intervention. Conclusions: MRI guided Co-60 therapy needs the output of all sources yet suffers from unintuitive and laborious manual beam selection processes. Automated triplet orientation optimization is shown essential to overcome the difficulty and improves the dosimetry. A novel FMO with regularization provides additional controls over the number of MLC segments

  10. Feasibility study of local ultrasound hyperthermia in cancer therapy

    International Nuclear Information System (INIS)

    Jones, K.G.; Straube, W.; Emami, B.; Perez, C.A.

    1987-01-01

    This paper describes a retrospective analysis of patients treated at Washington University for recurrent or persistent cancer with Ultrasound Hyperthermia between October 1984 and June 1986. Fifteen of 102 lesions were treated during this time period with Ultrasound Hyperthermia instead of microwave hyperthermia due to the size of the lesion needing heat at depths greater than 4 cm. Also, the patients' lesion could not be implanted for interstitial microwave hyperthermia. Fourteen of the treated patients received concomitant radiotherapy, while one received concomitant Bleomycin. There were 79 total hyperthermia treatments delivered, of which 67 achieved a therapeutic temperature of 43 0 C for 60 minutes. During 15/79 treatments, patients experienced pain; of which 11/15 lead to poor heating. Only one treatment of the twelve poor treatments was secondary to technical difficulties. Complete local control was accomplished in seven patients, a partial response in four patients. The results of therapeutic heating and its relationship to the site of treatment and local control are presented, along with phantom studies of Ultrasound microwave hyperthermia reemphasizing the feasibility of using Ultrasound Hyperthermia

  11. In-bore setup and software for 3T MRI-guided transperineal prostate biopsy

    International Nuclear Information System (INIS)

    Tokuda, Junichi; Tuncali, Kemal; Song, Sang-Eun; Fedorov, Andriy; Oguro, Sota; Fennessy, Fiona M; Tempany, Clare M; Hata, Nobuhiko; Iordachita, Iulian; Lasso, Andras

    2012-01-01

    MRI-guided prostate biopsy in conventional closed-bore scanners requires transferring the patient outside the bore during needle insertion due to the constrained in-bore space, causing a safety hazard and limiting image feedback. To address this issue, we present our custom-made in-bore setup and software to support MRI-guided transperineal prostate biopsy in a wide-bore 3 T MRI scanner. The setup consists of a specially designed tabletop and a needle-guiding template with a Z-frame that gives a physician access to the perineum of the patient at the imaging position and allows the physician to perform MRI-guided transperineal biopsy without moving the patient out of the scanner. The software and Z-frame allow registration of the template, target planning and biopsy guidance. Initially, we performed phantom experiments to assess the accuracy of template registration and needle placement in a controlled environment. Subsequently, we embarked on our clinical trial (N = 10). The phantom experiments showed that the translational errors of the template registration along the right–left (RP) and anterior–posterior (AP) axes were 1.1 ± 0.8 and 1.4 ± 1.1 mm, respectively, while the rotational errors around the RL, AP and superior–inferior axes were (0.8 ± 1.0)°, (1.7 ± 1.6)° and (0.0 ± 0.0)°, respectively. The 2D root-mean-square (RMS) needle-placement error was 3 mm. The clinical biopsy procedures were safely carried out in all ten clinical cases with a needle-placement error of 5.4 mm (2D RMS). In conclusion, transperineal prostate biopsy in a wide-bore 3T scanner is feasible using our custom-made tabletop setup and software, which supports manual needle placement without moving the patient out of the magnet. (paper)

  12. MRI-Guided Percutaneous Biopsy of Mediastinal Masses Using a Large Bore Magnet: Technical Feasibility

    Energy Technology Data Exchange (ETDEWEB)

    Garnon, J., E-mail: juliengarnon@gmail.com [Nouvel Hôpital Civil, Department of Interventional Radiology (France); Ramamurthy, N., E-mail: nitin-ramamurthy@hotmail.com [Norfolk and Norwich University Hospital, Department of Radiology (United Kingdom); Caudrelier J, J., E-mail: caudjean@yahoo.fr [Nouvel Hôpital Civil, Department of Interventional Radiology (France); Erceg, G., E-mail: erceggorislav@yahoo.com; Breton, E., E-mail: ebreton@unistra.fr [ICube, University of Strasbourg, CNRS (France); Tsoumakidou, G., E-mail: gtsoumakidou@yahoo.com; Rao, P., E-mail: pramodrao@me.com; Gangi, A., E-mail: gangi@unistra.fr [Nouvel Hôpital Civil, Department of Interventional Radiology (France)

    2016-05-15

    ObjectiveTo evaluate the diagnostic accuracy and safety of magnetic resonance imaging (MRI)-guided percutaneous biopsy of mediastinal masses performed using a wide-bore high-field scanner.Materials and MethodsThis is a retrospective study of 16 consecutive patients (8 male, 8 female; mean age 74 years) who underwent MRI-guided core needle biopsy of a mediastinal mass between February 2010 and January 2014. Size and location of lesion, approach taken, time for needle placement, overall duration of procedure, and post-procedural complications were evaluated. Technical success rates and correlation with surgical pathology (where available) were assessed.ResultsTarget lesions were located in the anterior (n = 13), middle (n = 2), and posterior mediastinum (n = 1), respectively. Mean size was 7.2 cm (range 3.6–11 cm). Average time for needle placement was 9.4 min (range 3–18 min); average duration of entire procedure was 42 min (range 27–62 min). 2–5 core samples were obtained from each lesion (mean 2.6). Technical success rate was 100 %, with specimens successfully obtained in all 16 patients. There were no immediate complications. Histopathology revealed malignancy in 12 cases (4 of which were surgically confirmed), benign lesions in 3 cases (1 of which was false negative following surgical resection), and one inconclusive specimen (treated as inaccurate since repeat CT-guided biopsy demonstrated thymic hyperplasia). Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy in our study were 92.3, 100, 100, 66.7, and 87.5 %, respectively.ConclusionMRI-guided mediastinal biopsy is a safe procedure with high diagnostic accuracy, which may offer a non-ionizing alternative to CT guidance.

  13. Combined treatment of radiotherapy and local hyperthermia using 8 MHz RF-wave for advanced carcinoma of the breast

    International Nuclear Information System (INIS)

    Fuwa, Nobukazu

    1988-01-01

    During the period from January 1983 through September 1986, 13 patients with carcinoma of the breast were treated with local hyperthermia combined with radiotherapy. Six patients were inoperable advanced cases and the other 7 were recurrent cases. Local heat was applied with an 8-MHz RF-capacitive heating equipment, once or twice a week after radiotherapy, for 40 ∼ 60 minutes per session. Of the 6 cases with inoperable advanced lesions, 4 achieved CR and the other 2 achieved PRa (80 ∼ 100 % regression), and of the 7 cases with local recurrent tumors, 3 achieved CR and the other 4 achieved PRa. As complications of the thermoradiotherapy, grade I-II skin burns were observed in 9 cases, pain around the ribs in 8 cases, mild lassitude in 2 cases, persistent tachycardia in 1 case and acute erosive gastritis in 1 case. It is worth noting that CR was achieved in these huge tumors, which can not be controlled by radiotherapy alone. (author)

  14. Hyperthermia: Clinical promise and current challenges

    International Nuclear Information System (INIS)

    Kapp, D.S.

    1987-01-01

    Local-regional hyperthermia (HT) when used in conjunction with radiation therapy (XRT), has been shown in numerous clinical trials to result in considerable improvement in response rates and local tumor control rates when compared with treatment by XRT alone. Although considerable progress has been made in understanding the biological basis for hyperthermia induced cytotoxicity and radiosensitization, additional research remains in establishing the optimal treatment schedules for the clinical utilization of HT-XRT. The number of HT treatments; the sequencing of HT and XRT; the frequency of administration of HT; and the ideal temperature-time parameters all remain to be better defined for the clinical setting. The role of tumor blood flow on the thermal distributions also warrants further investigation. In addition, considerable effort is needed to improve hyperthermia equipment in order to provide more uniform therapeutic temperature distributions (temperatures ≥42.5%C). Better heating equipment is particularly needed for the treatment of deep seeted tumors. Pertinent clinical literature will be presented summarizing the clinical promise of hyperthermia and the above mentioned clinical challenges

  15. Hyperthermia and radiotherapy

    International Nuclear Information System (INIS)

    Lindholm, C.E.

    1992-01-01

    Combined hyperthermia (HT 45 min once or twice per week) and low dose radiotherapy (LDRT 30-34.5 Gy in 2-3 weeks) have been given to 182 locally recurrent or metastatic superficial tumours in 133 patients. Tumour response was analysed in 137 tumours in 100 patients. The overall complete response (CR) was 50% with a median duration (DCR) of 13±3 months. When mammary carcinoma, representing 62% of the treated tumours, were analysed, CR was 62% with a DCR of 14±4 months. In a comparative, non-randomized study, on 34 matched tumour pairs in 24 patients, treatment was given with LDRT+HT to the larger and the same LDRT to the smaller tumour, the patients acting as their own control. A significant difference in CR was obtained in favour of the combined treatment (p=0.0013 all diagnosis and p=0.0027 mammary carcinoma). There was no significant difference in DCR between the two modalities. No significant difference in CR was seen when tumours were randomely treated with HT once (CR 56%) or twice (CR 69%) per week combined with the same LDRT. Predictive factors for CR, multivariately analysed (15 parameters), in mammary carcinoma recurring in earlier irradiated regions, were; the present LDRT absorbed dose (p=0.02) and the average minimum temperature in the best HT session (p=0.03). Significant skin toxicity was seen in 28% of all the 182 heated regions. Prognostic factors for skin damage, multivariately analysed, were; the extension of the heated region (p=0.007) and the highest average maximum temperature in any of the HT sessions (p=0.04). Pain was in some way correlated to severe toxicity but was not considered to be an optimal monitor for HT as many patients with severe and moderate pain were without any serious skin reactions, while slight or no pain sometimes were associated with severe reactions. 401 refs

  16. Daily Tracking of Glioblastoma Resection Cavity, Cerebral Edema, and Tumor Volume with MRI-Guided Radiation Therapy.

    Science.gov (United States)

    Mehta, Shahil; Gajjar, Shefali R; Padgett, Kyle R; Asher, David; Stoyanova, Radka; Ford, John C; Mellon, Eric A

    2018-03-19

    Radiation therapy (RT) plays a critical role in the treatment of glioblastoma. Studies of brain imaging during RT for glioblastoma have demonstrated changes in the brain during RT. However, frequent or daily utilization of standalone magnetic resonance imaging (MRI) scans during RT have limited feasibility. The recent release of the tri-cobalt-60 MRI-guided RT (MR-IGRT) device (ViewRay MRIdian, Cleveland, OH) allows for daily brain MRI for the RT setup. Daily MRI of three postoperative patients undergoing RT and temozolomide for glioblastoma over a six-week course allowed for the identification of changes to the cavity, edema, and visible tumor on a daily basis. The volumes and dimensions of the resection cavities, edema, and T2-hyperintense tumor were measured. A general trend of daily decreases in cavity measurements was observed in all patients. For the one patient with edema, a trend of daily increases followed by a trend of daily decreases were observed. These results suggest that daily MRI could be used for onboard resimulation and adaptive RT for future fluctuations in the sizes of brain tumors, cavities, or cystic components. This could improve tumor targeting and reduce RT of healthy brain tissue.

  17. First clinical experience with a dedicated MRI-guided high-intensity focused ultrasound system for breast cancer ablation

    Energy Technology Data Exchange (ETDEWEB)

    Merckel, Laura G.; Knuttel, Floor M.; Peters, Nicky H.G.M.; Mali, Willem P.T.M.; Bosch, Maurice A.A.J. van den [University Medical Center Utrecht, Department of Radiology, HP E 01.132, Utrecht (Netherlands); Deckers, Roel; Moonen, Chrit T.W.; Bartels, Lambertus W. [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands); Dalen, Thijs van [Diakonessenhuis Utrecht, Department of Surgery, Utrecht (Netherlands); Schubert, Gerald [Philips Healthcare, Best (Netherlands); Weits, Teun [Diakonessenhuis Utrecht, Department of Radiology, Utrecht (Netherlands); Diest, Paul J. van [University Medical Center Utrecht, Department of Pathology, Utrecht (Netherlands); Vaessen, Paul H.H.B. [University Medical Center Utrecht, Department of Anesthesiology, Utrecht (Netherlands); Gorp, Joost M.H.H. van [Diakonessenhuis Utrecht, Department of Pathology, Utrecht (Netherlands)

    2016-11-15

    To assess the safety and feasibility of MRI-guided high-intensity focused ultrasound (MR-HIFU) ablation in breast cancer patients using a dedicated breast platform. Patients with early-stage invasive breast cancer underwent partial tumour ablation prior to surgical resection. MR-HIFU ablation was performed using proton resonance frequency shift MR thermometry and an MR-HIFU system specifically designed for breast tumour ablation. The presence and extent of tumour necrosis was assessed by histopathological analysis of the surgical specimen. Pearson correlation coefficients were calculated to assess the relationship between sonication parameters, temperature increase and size of tumour necrosis at histopathology. Ten female patients underwent MR-HIFU treatment. No skin redness or burns were observed in any of the patients. No correlation was found between the applied energy and the temperature increase. In six patients, tumour necrosis was observed with a maximum diameter of 3-11 mm. In these patients, the number of targeted locations was equal to the number of areas with tumour necrosis. A good correlation was found between the applied energy and the size of tumour necrosis at histopathology (Pearson = 0.76, p = 0.002). Our results show that MR-HIFU ablation with the dedicated breast system is safe and results in histopathologically proven tumour necrosis. (orig.)

  18. Evaluation of a robotic technique for transrectal MRI-guided prostate biopsies

    Energy Technology Data Exchange (ETDEWEB)

    Schouten, Martijn G. [Radboud University Nijmegen Medical Centre, Department of Radiology, Nijmegen (Netherlands); University Medical Centre Nijmegen, Department of Radiology, Nijmegen (Netherlands); Bomers, Joyce G.R.; Yakar, Derya; Huisman, Henkjan; Bosboom, Dennis; Scheenen, Tom W.J.; Fuetterer, Jurgen J. [Radboud University Nijmegen Medical Centre, Department of Radiology, Nijmegen (Netherlands); Rothgang, Eva [Pattern Recognition Lab, Friedrich-Alexander-University of Erlangen-Nuremberg, Erlangen (Germany); Center for Applied Medical Imaging, Siemens Corporate Research (Germany); Center for Applied Medical Imaging, Siemens Corporate Research, Baltimore, MD (United States); Misra, Sarthak [University of Twente, MIRA-Institute of Biomedical Technology and Technical Medicine, Enschede (Netherlands)

    2012-02-15

    To evaluate the accuracy and speed of a novel robotic technique as an aid to perform magnetic resonance image (MRI)-guided prostate biopsies on patients with cancer suspicious regions. A pneumatic controlled MR-compatible manipulator with 5 degrees of freedom was developed in-house to guide biopsies under real-time imaging. From 13 consecutive biopsy procedures, the targeting error, biopsy error and target displacement were calculated to evaluate the accuracy. The time was recorded to evaluate manipulation and procedure time. The robotic and manual techniques demonstrated comparable results regarding mean targeting error (5.7 vs 5.8 mm, respectively) and mean target displacement (6.6 vs 6.0 mm, respectively). The mean biopsy error was larger (6.5 vs 4.4 mm) when using the robotic technique, although not significant. Mean procedure and manipulation time were 76 min and 6 min, respectively using the robotic technique and 61 and 8 min with the manual technique. Although comparable results regarding accuracy and speed were found, the extended technical effort of the robotic technique make the manual technique - currently - more suitable to perform MRI-guided biopsies. Furthermore, this study provided a better insight in displacement of the target during in vivo biopsy procedures. (orig.)

  19. Evaluation of a robotic technique for transrectal MRI-guided prostate biopsies

    International Nuclear Information System (INIS)

    Schouten, Martijn G.; Bomers, Joyce G.R.; Yakar, Derya; Huisman, Henkjan; Bosboom, Dennis; Scheenen, Tom W.J.; Fuetterer, Jurgen J.; Rothgang, Eva; Misra, Sarthak

    2012-01-01

    To evaluate the accuracy and speed of a novel robotic technique as an aid to perform magnetic resonance image (MRI)-guided prostate biopsies on patients with cancer suspicious regions. A pneumatic controlled MR-compatible manipulator with 5 degrees of freedom was developed in-house to guide biopsies under real-time imaging. From 13 consecutive biopsy procedures, the targeting error, biopsy error and target displacement were calculated to evaluate the accuracy. The time was recorded to evaluate manipulation and procedure time. The robotic and manual techniques demonstrated comparable results regarding mean targeting error (5.7 vs 5.8 mm, respectively) and mean target displacement (6.6 vs 6.0 mm, respectively). The mean biopsy error was larger (6.5 vs 4.4 mm) when using the robotic technique, although not significant. Mean procedure and manipulation time were 76 min and 6 min, respectively using the robotic technique and 61 and 8 min with the manual technique. Although comparable results regarding accuracy and speed were found, the extended technical effort of the robotic technique make the manual technique - currently - more suitable to perform MRI-guided biopsies. Furthermore, this study provided a better insight in displacement of the target during in vivo biopsy procedures. (orig.)

  20. Fiber Optic Force Sensors for MRI-Guided Interventions and Rehabilitation: A Review

    Science.gov (United States)

    Iordachita, Iulian I.; Tokuda, Junichi; Hata, Nobuhiko; Liu, Xuan; Seifabadi, Reza; Xu, Sheng; Wood, Bradford; Fischer, Gregory S.

    2017-01-01

    Magnetic Resonance Imaging (MRI) provides both anatomical imaging with excellent soft tissue contrast and functional MRI imaging (fMRI) of physiological parameters. The last two decades have witnessed the manifestation of increased interest in MRI-guided minimally invasive intervention procedures and fMRI for rehabilitation and neuroscience research. Accompanying the aspiration to utilize MRI to provide imaging feedback during interventions and brain activity for neuroscience study, there is an accumulated effort to utilize force sensors compatible with the MRI environment to meet the growing demand of these procedures, with the goal of enhanced interventional safety and accuracy, improved efficacy and rehabilitation outcome. This paper summarizes the fundamental principles, the state of the art development and challenges of fiber optic force sensors for MRI-guided interventions and rehabilitation. It provides an overview of MRI-compatible fiber optic force sensors based on different sensing principles, including light intensity modulation, wavelength modulation, and phase modulation. Extensive design prototypes are reviewed to illustrate the detailed implementation of these principles. Advantages and disadvantages of the sensor designs are compared and analyzed. A perspective on the future development of fiber optic sensors is also presented which may have additional broad clinical applications. Future surgical interventions or rehabilitation will rely on intelligent force sensors to provide situational awareness to augment or complement human perception in these procedures. PMID:28652857

  1. Fiber Optic Force Sensors for MRI-Guided Interventions and Rehabilitation: A Review.

    Science.gov (United States)

    Su, Hao; Iordachita, Iulian I; Tokuda, Junichi; Hata, Nobuhiko; Liu, Xuan; Seifabadi, Reza; Xu, Sheng; Wood, Bradford; Fischer, Gregory S

    2017-04-01

    Magnetic Resonance Imaging (MRI) provides both anatomical imaging with excellent soft tissue contrast and functional MRI imaging (fMRI) of physiological parameters. The last two decades have witnessed the manifestation of increased interest in MRI-guided minimally invasive intervention procedures and fMRI for rehabilitation and neuroscience research. Accompanying the aspiration to utilize MRI to provide imaging feedback during interventions and brain activity for neuroscience study, there is an accumulated effort to utilize force sensors compatible with the MRI environment to meet the growing demand of these procedures, with the goal of enhanced interventional safety and accuracy, improved efficacy and rehabilitation outcome. This paper summarizes the fundamental principles, the state of the art development and challenges of fiber optic force sensors for MRI-guided interventions and rehabilitation. It provides an overview of MRI-compatible fiber optic force sensors based on different sensing principles, including light intensity modulation, wavelength modulation, and phase modulation. Extensive design prototypes are reviewed to illustrate the detailed implementation of these principles. Advantages and disadvantages of the sensor designs are compared and analyzed. A perspective on the future development of fiber optic sensors is also presented which may have additional broad clinical applications. Future surgical interventions or rehabilitation will rely on intelligent force sensors to provide situational awareness to augment or complement human perception in these procedures.

  2. Cellular and tissue effects of hyperthermia and radiation

    International Nuclear Information System (INIS)

    Field, S.B.

    1989-01-01

    This paper presents the idea that hyperthermia is likely to be most effective in poorly perfused regions, which is where radiotherapy and chemotherapy are least effective. The author suggests that a therapeutic gain might, therefore, be obtained by combined treatments

  3. A novel approach of fMRI-guided tractography analysis within a group: construction of an fMRI-guided tractographic atlas.

    Science.gov (United States)

    Preti, Maria Giulia; Makris, Nikos; Laganà, Maria Marcella; Papadimitriou, George; Baglio, Francesca; Griffanti, Ludovica; Nemni, Raffaello; Cecconi, Pietro; Westin, Carl-Fredrik; Baselli, Giuseppe

    2012-01-01

    Diffusion Tensor Imaging (DTI) tractography and functional Magnetic Resonance Imaging (fMRI) investigate two complementary aspects of brain networks: white matter (WM) anatomical connectivity and gray matter (GM) function. However, integration standards have yet to be defined; namely, individual fMRI-driven tractography is usually applied and only few studies address group analysis. This work proposes an efficient method of fMRI-driven tractography at group level through the creation of a tractographic atlas starting from the GM areas activated by a verbal fluency task in 11 healthy subjects. The individual tracts were registered to the MNI space. Selection ROIs derived by GM masking and dilation of group activated areas were applied to obtain the fMRI-driven subsets within tracts. An atlas of the tracts recruited among the population was obtained by selecting for each subject the fMRI-guided tracts passing through the high probability voxels (the voxels recruited by the 90% of the subjects) and merging them together. The reliability of this approach was assessed by comparing it with the probabilistic atlas previously introduced in literature. The introduced method allowed to successfully reconstruct activated tracts, which comprehended corpus callosum, left cingulum and arcuate, a small portion of the right arcuate, both cortico-spinal tracts and inferior fronto-occipital fasciculi. Moreover, it proved to give results concordant with the previously introduced probabilistic approach, allowing in addition to reconstruct 3D trajectories of the activated fibers, which appear particularly helpful in the detection of WM connections.

  4. Ultrasound-guided percutaneous treatment of hepatocellular carcinoma by radiofrequency hyperthermia with a 'cooled-tip needle'. A preliminary clinical experience.

    Science.gov (United States)

    Francica, G; Marone, G

    1999-05-01

    three recorded deaths, two were due to intrahepatic tumor diffusion. In our experience radiofrequency hyperthermia with the cooled-tip needle afforded an effective and safe percutaneous ablative method for HCC in cirrhosis and shortened treatment time.

  5. Current Status and Perspectives of Hyperthermia in Cancer Therapy

    Science.gov (United States)

    Hiraoka, Masahiro; Nagata, Yasushi; Mitsumori, Michihide; Sakamoto, Masashi; Masunaga, Shin-ichiro

    2004-08-01

    Clinical trials of hyperthermia in combination with radiation therapy or chemotherapy undertaken over the past decades in Japan have been reviewed. Originally developed heating devices were mostly used for these trials, which include RF (radiofrequency) capacitive heating devices, a microwave heating device with a lens applicator, an RF intracavitary heating device, an RF current interstitial heating device, and ferromagnetic implant heating device. Non-randomized trials for various cancers, demonstrated higher response rate in thermoradiotherapy than in radiotherapy alone. Randomized trials undertaken for esophageal cancers also demonstrated improved local response with the combined use of hyperthermia. Furthermore, the complications associated with treatment were not generally serious. These clinical results indicate the benefit of combined treatment of hyperthermia and radiotherapy for various malignancies. On the other hand, the presently available heating devices are not satisfactory from the clinical viewpoints. With the advancement of heating and thermometry technologies, hyperthermia will be more widely and safely used in the treatment of cancers.

  6. Can we settle with single-band radiometric temperature monitoring during hyperthermia treatment of chestwall recurrence of breast cancer using a dual-mode transceiving applicator?

    Energy Technology Data Exchange (ETDEWEB)

    Jacobsen, Svein [Electrical Engineering Group, Department of Physics and Technology, Faculty of Science, University of Tromsoe, N-9037 Tromsoe (Norway); Stauffer, Paul R [Radiation Oncology Department, University of California at San Francisco, San Francisco, CA 94143 (United States)

    2007-02-21

    The total thermal dose that can be delivered during hyperthermia treatments is frequently limited by temperature heterogeneities in the heated tissue volume. Reliable temperature information on the heated area is thus vital for the optimization of clinical dosimetry. Microwave radiometry has been proposed as an accurate, quick and painless temperature sensing technique for biological tissue. Advantages include the ability to sense volume-averaged temperatures from subsurface tissue non-invasively, rather than with a limited set of point measurements typical of implanted temperature probes. We present a procedure to estimate the maximum tissue temperature from a single radiometric brightness temperature which is based on a numerical simulation of 3D tissue temperature distributions induced by microwave heating at 915 MHz. The temperature retrieval scheme is evaluated against errors arising from unknown variations in thermal, electromagnetic and design model parameters. Whereas realistic deviations from base values of dielectric and thermal parameters have only marginal impact on performance, pronounced deviations in estimated maximum tissue temperature are observed for unanticipated variations of the temperature or thickness of the bolus compartment. The need to pay particular attention to these latter applicator construction parameters in future clinical implementation of the thermometric method is emphasized.

  7. Can we settle with single-band radiometric temperature monitoring during hyperthermia treatment of chestwall recurrence of breast cancer using a dual-mode transceiving applicator?

    International Nuclear Information System (INIS)

    Jacobsen, Svein; Stauffer, Paul R

    2007-01-01

    The total thermal dose that can be delivered during hyperthermia treatments is frequently limited by temperature heterogeneities in the heated tissue volume. Reliable temperature information on the heated area is thus vital for the optimization of clinical dosimetry. Microwave radiometry has been proposed as an accurate, quick and painless temperature sensing technique for biological tissue. Advantages include the ability to sense volume-averaged temperatures from subsurface tissue non-invasively, rather than with a limited set of point measurements typical of implanted temperature probes. We present a procedure to estimate the maximum tissue temperature from a single radiometric brightness temperature which is based on a numerical simulation of 3D tissue temperature distributions induced by microwave heating at 915 MHz. The temperature retrieval scheme is evaluated against errors arising from unknown variations in thermal, electromagnetic and design model parameters. Whereas realistic deviations from base values of dielectric and thermal parameters have only marginal impact on performance, pronounced deviations in estimated maximum tissue temperature are observed for unanticipated variations of the temperature or thickness of the bolus compartment. The need to pay particular attention to these latter applicator construction parameters in future clinical implementation of the thermometric method is emphasized

  8. Intraoperative MRI-guided resection of focal cortical dysplasia in pediatric patients: technique and outcomes.

    Science.gov (United States)

    Sacino, Matthew F; Ho, Cheng-Ying; Murnick, Jonathan; Tsuchida, Tammy; Magge, Suresh N; Keating, Robert F; Gaillard, William D; Oluigbo, Chima O

    2016-06-01

    OBJECTIVE Previous meta-analysis has demonstrated that the most important factor in seizure freedom following surgery for focal cortical dysplasia (FCD) is completeness of resection. However, intraoperative detection of epileptogenic dysplastic cortical tissue remains a challenge, potentially leading to a partial resection and the need for reoperation. The objective of this study was to determine the role of intraoperative MRI (iMRI) in the intraoperative detection and localization of FCD as well as its impact on surgical decision making, completeness of resection, and seizure control outcomes. METHODS The authors retrospectively reviewed the medical records of pediatric patients who underwent iMRI-assisted resection of FCD at the Children's National Health System between January 2014 and April 2015. Data reviewed included demographics, length of surgery, details of iMRI acquisition, postoperative seizure freedom, and complications. Postsurgical seizure outcome was assessed utilizing the Engel Epilepsy Surgery Outcome Scale. RESULTS Twelve consecutive pediatric patients (8 females and 4 males) underwent iMRI-guided resection of FCD lesions. The mean age at the time of surgery was 8.8 years ± 1.6 years (range 0.7 to 18.8 years), and the mean duration of follow up was 3.5 months ± 1.0 month. The mean age at seizure onset was 2.8 years ± 1.0 year (range birth to 9.0 years). Two patients had Type 1 FCD, 5 patients had Type 2A FCD, 2 patients had Type 2B FCD, and 3 patients had FCD of undetermined classification. iMRI findings impacted intraoperative surgical decision making in 5 (42%) of the 12 patients, who then underwent further exploration of the resection cavity. At the time of the last postoperative follow-up, 11 (92%) of the 12 patients were seizure free (Engel Class I). No patients underwent reoperation following iMRI-guided surgery. CONCLUSIONS iMRI-guided resection of FCD in pediatric patients precluded the need for repeat surgery. Furthermore, it resulted

  9. Shoulder-Mounted Robot for MRI-guided arthrography: Accuracy and mounting study.

    Science.gov (United States)

    Monfaredi, R; Wilson, E; Sze, R; Sharma, K; Azizi, B; Iordachita, I; Cleary, K

    2015-08-01

    A new version of our compact and lightweight patient-mounted MRI-compatible 4 degree-of-freedom (DOF) robot for MRI-guided arthrography procedures is introduced. This robot could convert the traditional two-stage arthrography procedure (fluoroscopy-guided needle insertion followed by a diagnostic MRI scan) to a one-stage procedure, all in the MRI suite. The results of a recent accuracy study are reported. A new mounting technique is proposed and the mounting stability is investigated using optical and electromagnetic tracking on an anthropomorphic phantom. Five volunteer subjects including 2 radiologists were asked to conduct needle insertion in 4 different random positions and orientations within the robot's workspace and the displacement of the base of the robot was investigated during robot motion and needle insertion. Experimental results show that the proposed mounting method is stable and promising for clinical application.

  10. Towards Clinically Optimized MRI-guided Surgical Manipulator for Minimally Invasive Prostate Percutaneous Interventions: Constructive Design*

    Science.gov (United States)

    Eslami, Sohrab; Fischer, Gregory S.; Song, Sang-Eun; Tokuda, Junichi; Hata, Nobuhiko; Tempany, Clare M.; Iordachita, Iulian

    2013-01-01

    This paper undertakes the modular design and development of a minimally invasive surgical manipulator for MRI-guided transperineal prostate interventions. Severe constraints for the MRI-compatibility to hold the minimum artifact on the image quality and dimensions restraint of the bore scanner shadow the design procedure. Regarding the constructive design, the manipulator kinematics has been optimized and the effective analytical needle workspace is developed and followed by proposing the workflow for the manual needle insertion. A study of the finite element analysis is established and utilized to improve the mechanism weaknesses under some inevitable external forces to ensure the minimum structure deformation. The procedure for attaching a sterile plastic drape on the robot manipulator is discussed. The introduced robotic manipulator herein is aimed for the clinically prostate biopsy and brachytherapy applications. PMID:24683502

  11. ADPRT inhibitors and hyperthermia as radiosensitizers

    International Nuclear Information System (INIS)

    Jonsson, G.G.

    1985-01-01

    Hyperthermia given in combination with gamma radiation has given considerable improvement in the therapeutic results for treatment of malignant tumors. The mechanism behind the hyperthermia effect is probably operative at the tissue level as well as at the molecular level. The metabolism of NAD + in relation to the activity of the chromosomal enzyme ADP-ribosyl transferase (ADPRT) has been studied as a possible molecular mechanism for this effect. The ADPRT activity was measured after radiosensitization with both hyperthermia and nicotinamide, which is a potent inhibitor of ADPRT. The results indicate that hyperthermia can improve the effect of radiotherapy by reducing the supply of NAD + , which is a co-substrate for ADPRT, while nicotinamide functions as a radiosensitizing agent by direct inhibition of the enzyme. The hypothesis is discussed in the thesis where inhibition of ADPRT might increase the radiosensitivity because the radiation-induced DNA damage can not be repaired with normal efficiency. The function of nicotinamide as a radiosensitizer was verified by studies on C3H mice with transplanted spontaneous mammary tumors. Because nicotinamide is not toxic, it seems quite attractive to test this vitamin as a radiosensitizing agent against human tumors. (251 refs.) (author)

  12. MRI-guided robotic system for transperineal prostate interventions: proof of principle

    International Nuclear Information System (INIS)

    Van den Bosch, Michiel R; Moman, Maaike R; Van Vulpen, Marco; Battermann, Jan J; Lagendijk, Jan J W; Moerland, Marinus A; Duiveman, Ed; Van Schelven, Leonard J; De Leeuw, Hendrik

    2010-01-01

    In this study, we demonstrate the proof of principle of the University Medical Center Utrecht (UMCU) robot dedicated to magnetic resonance imaging (MRI)-guided interventions in patients. The UMCU robot consists of polymers and non-ferromagnetic materials. For transperineal prostate interventions, it can be placed between the patient's legs inside a closed bore 1.5T MR scanner. The robot can manually be translated and rotated resulting in five degrees of freedom. It contains a pneumatically driven tapping device to automatically insert a needle stepwise into the prostate using a controller unit outside the scanning room. To define the target positions and to verify the needle insertion point and the needle trajectory, a high-resolution 3D balanced steady state free precession (bSSFP) scan that provides a T2/T1-weighted contrast is acquired. During the needle insertion fast 2D bSSFP images are generated to track the needle on-line. When the target position is reached, the radiation oncologist manually places a fiducial gold marker (small seed) at this location. In total two needle trajectories are used to place all markers. Afterwards, a high-resolution 3D bSSFP scan is acquired to visualize the fiducial gold markers. Four fiducial gold markers were placed transperineally into the prostate of a patient with a clinical stage T3 prostate cancer. In the generated scans, it was possible to discriminate the patient's anatomy, the needle and the markers. All markers were delivered inside the prostate. The procedure time was 1.5 h. This study proves that MRI-guided needle placement and seed delivery in the prostate with the UMCU robot are feasible. (note)

  13. In-bore transrectal MRI-guided prostate biopsies: Are there risk factors for complications?

    Energy Technology Data Exchange (ETDEWEB)

    Meier-Schroers, Michael, E-mail: michael.meier@ukb.uni-bonn.de [Department of Radiology, University of Bonn, Sigmund-Freud-Str 25, 53127 Bonn (Germany); Homsi, Rami, E-mail: rami.homsi@ukb.uni-bonn.de [Department of Radiology, University of Bonn, Sigmund-Freud-Str 25, 53127 Bonn (Germany); Kukuk, Guido, E-mail: guido.kukuk@ukb.uni-bonn.de [Department of Radiology, University of Bonn, Sigmund-Freud-Str 25, 53127 Bonn (Germany); Wolter, Karsten, E-mail: karsten.wolter@ukb.uni-bonn.de [Department of Radiology, University of Bonn, Sigmund-Freud-Str 25, 53127 Bonn (Germany); Decker, Georges, E-mail: georges.decker@ukb.uni-bonn.de [Department of Radiology, University of Bonn, Sigmund-Freud-Str 25, 53127 Bonn (Germany); Fischer, Stefan, E-mail: stefan.fischer@ukb.uni-bonn.de [Department of Radiology, University of Bonn, Sigmund-Freud-Str 25, 53127 Bonn (Germany); Marx, Christian, E-mail: christian.marx@ukb.uni-bonn.de [Department of Radiology, University of Bonn, Sigmund-Freud-Str 25, 53127 Bonn (Germany); Schmeel, Frederic Carsten, E-mail: carsten.schmeel@ukb.uni-bonn.de [Department of Radiology, University of Bonn, Sigmund-Freud-Str 25, 53127 Bonn (Germany); Block, Wolfgang, E-mail: wolfgang.block@ukb.uni-bonn.de [Department of Radiology, University of Bonn, Sigmund-Freud-Str 25, 53127 Bonn (Germany); Sprinkart, Alois Martin, E-mail: sprinkart@uni-bonn.de [Department of Radiology, University of Bonn, Sigmund-Freud-Str 25, 53127 Bonn (Germany); Traeber, Frank, E-mail: frank.traeber@ukb.uni-bonn.de [Department of Radiology, University of Bonn, Sigmund-Freud-Str 25, 53127 Bonn (Germany); Schild, Hans Heinz, E-mail: hans.schild@ukb.uni-bonn.de [Department of Radiology, University of Bonn, Sigmund-Freud-Str 25, 53127 Bonn (Germany); Willinek, Winfried, E-mail: w.willinek@bk-trier.de [Department of Radiology, Neuroradiology, Sonography and Nuclear Medicine, Hospital of the Barmherzige Brüder Trier, Nordallee 1, 54292 Trier (Germany)

    2016-12-15

    Purpose: To systematically analyze risk factors for complications of in-bore transrectal MRI-guided prostate biopsies (MRGB). Materials and methods: 90 patients, who were scheduled for MRGB were included for this study. Exclusion criteria were coagulation disorders, therapy with anticoagulant drugs, and acute infections of the urinary and the lower gastrointestinal tract. Directly after, one week and one year after the biopsy, we assessed biopsy related complications (e.g. hemorrhages or signs of prostatitis). Differences between patients with and without complications were analyzed regarding possible risk factors: age, prostate volume, number of taken samples, biopsy duration, biopsy of more than one lesion, diabetes, arterial hypertension, hemorrhoids, benign prostate hyperplasia, carcinoma or prostatitis (according to histopathological analysis), and lesion localization. Complications were classified according to the Clavien-Dindo classification. Results: We observed 15 grade I complications in 90 biopsies (16.7%) with slight hematuria in 9 cases (10%), minor vasovagal reactions in 4 cases (4.4%), and urinary retention and positioning-related facial dysesthesia in 1 case each (1.1%). One patient showed acute prostatitis requiring antibiotics as the only grade II complication (1.1%). There were no adverse events that occurred later than one week. Complications grade III or higher such as pelvic abscesses, urosepsis or severe hemorrhages were not seen. There were no significant associations between the assessed risk factors and biopsy-related complications. Conclusion: In-bore transrectal MRI-guided prostate biopsies can be considered safe procedures in the diagnosis of prostate cancer with very low complication rates. There seem to be no risk factors for complications.

  14. Diagnostic Accuracy of MRI-guided Percutaneous Transthoracic Needle Biopsy of Solitary Pulmonary Nodules

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shangang, E-mail: 1198685580@qq.com [University of Jinan-Shandong Academy of Medical Science, Department of Radiation Oncology, Shandong Cancer Hospital and Institute, School of Medicine and Life Sciences (China); Li, Chengli, E-mail: chenglilichina@yeah.net [Shandong University, Department of Interventional MRI, Shandong Medical Imaging Research Institute (China); Yu, Xuejuan, E-mail: yuxuejuan2011@126.com [University of Jinan-Shandong Academy of Medical Science, Department of Radiation Oncology, Shandong Cancer Hospital and Institute, School of Medicine and Life Sciences (China); Liu, Ming, E-mail: mingliuyxs@163.com [Shandong University, Department of Interventional MRI, Shandong Medical Imaging Research Institute (China); Fan, Tingyong, E-mail: FTY681105@sohu.com; Chen, Dong, E-mail: 857984870@qq.com; Zhang, Pinliang, E-mail: zhangpinliang@163.com; Ren, Ruimei, E-mail: liusg708@qq.com [University of Jinan-Shandong Academy of Medical Science, Department of Radiation Oncology, Shandong Cancer Hospital and Institute, School of Medicine and Life Sciences (China)

    2015-04-15

    ObjectiveThe purpose of our study was to evaluate the diagnostic accuracy of MRI-guided percutaneous transthoracic needle biopsy (PTNB) of solitary pulmonary nodules (SPNs).MethodsRetrospective review of 69 patients who underwent MR-guided PTNB of SPNs was performed. Each case was reviewed for complications. The final diagnosis was established by surgical pathology of the nodule or clinical and imaging follow-up. Pneumothorax rate and diagnostic accuracy were compared between two groups according to nodule diameter (≤2 vs. >2 cm) using χ{sup 2} chest and Fisher’s exact test, respectively.ResultsThe success rate of single puncture was 95.6 %. Twelve (17.4 %) patients had pneumothorax, with 1 (1.4 %) requiring chest tube insertion. Mild hemoptysis occurred in 7 (7.2 %) patients. All of the sample material was sufficient for histological diagnostic evaluation. Pathological analysis of biopsy specimens showed 46 malignant, 22 benign, and 1 nondiagnostic nodule. The final diagnoses were 49 malignant nodules and 20 benign nodules basing on postoperative histopathology and clinical follow-up data. One nondiagnostic sample was excluded from calculating diagnostic performance. A sensitivity, specificity, accuracy, positive predictive value, and negative predictive value in diagnosing SPNs were 95.8, 100, 97.0, 100, and 90.9 %, respectively. Pneumothorax rate, diagnostic sensitivity, and accuracy were not significantly different between the two groups (P > 0.05).ConclusionsMRI-guided PTNB is safe, feasible, and high accurate diagnostic technique for pathologic diagnosis of pulmonary nodules.

  15. MRI-guided robotic system for transperineal prostate interventions: proof of principle

    Energy Technology Data Exchange (ETDEWEB)

    Van den Bosch, Michiel R; Moman, Maaike R; Van Vulpen, Marco; Battermann, Jan J; Lagendijk, Jan J W; Moerland, Marinus A [Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht (Netherlands); Duiveman, Ed; Van Schelven, Leonard J [Medical Technology and Clinical Physics, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht (Netherlands); De Leeuw, Hendrik [Image Sciences Institute, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht (Netherlands)], E-mail: M.R.vandenBosch@umcutrecht.nl

    2010-03-07

    In this study, we demonstrate the proof of principle of the University Medical Center Utrecht (UMCU) robot dedicated to magnetic resonance imaging (MRI)-guided interventions in patients. The UMCU robot consists of polymers and non-ferromagnetic materials. For transperineal prostate interventions, it can be placed between the patient's legs inside a closed bore 1.5T MR scanner. The robot can manually be translated and rotated resulting in five degrees of freedom. It contains a pneumatically driven tapping device to automatically insert a needle stepwise into the prostate using a controller unit outside the scanning room. To define the target positions and to verify the needle insertion point and the needle trajectory, a high-resolution 3D balanced steady state free precession (bSSFP) scan that provides a T2/T1-weighted contrast is acquired. During the needle insertion fast 2D bSSFP images are generated to track the needle on-line. When the target position is reached, the radiation oncologist manually places a fiducial gold marker (small seed) at this location. In total two needle trajectories are used to place all markers. Afterwards, a high-resolution 3D bSSFP scan is acquired to visualize the fiducial gold markers. Four fiducial gold markers were placed transperineally into the prostate of a patient with a clinical stage T3 prostate cancer. In the generated scans, it was possible to discriminate the patient's anatomy, the needle and the markers. All markers were delivered inside the prostate. The procedure time was 1.5 h. This study proves that MRI-guided needle placement and seed delivery in the prostate with the UMCU robot are feasible. (note)

  16. In-bore transrectal MRI-guided prostate biopsies: Are there risk factors for complications?

    International Nuclear Information System (INIS)

    Meier-Schroers, Michael; Homsi, Rami; Kukuk, Guido; Wolter, Karsten; Decker, Georges; Fischer, Stefan; Marx, Christian; Schmeel, Frederic Carsten; Block, Wolfgang; Sprinkart, Alois Martin; Traeber, Frank; Schild, Hans Heinz; Willinek, Winfried

    2016-01-01

    Purpose: To systematically analyze risk factors for complications of in-bore transrectal MRI-guided prostate biopsies (MRGB). Materials and methods: 90 patients, who were scheduled for MRGB were included for this study. Exclusion criteria were coagulation disorders, therapy with anticoagulant drugs, and acute infections of the urinary and the lower gastrointestinal tract. Directly after, one week and one year after the biopsy, we assessed biopsy related complications (e.g. hemorrhages or signs of prostatitis). Differences between patients with and without complications were analyzed regarding possible risk factors: age, prostate volume, number of taken samples, biopsy duration, biopsy of more than one lesion, diabetes, arterial hypertension, hemorrhoids, benign prostate hyperplasia, carcinoma or prostatitis (according to histopathological analysis), and lesion localization. Complications were classified according to the Clavien-Dindo classification. Results: We observed 15 grade I complications in 90 biopsies (16.7%) with slight hematuria in 9 cases (10%), minor vasovagal reactions in 4 cases (4.4%), and urinary retention and positioning-related facial dysesthesia in 1 case each (1.1%). One patient showed acute prostatitis requiring antibiotics as the only grade II complication (1.1%). There were no adverse events that occurred later than one week. Complications grade III or higher such as pelvic abscesses, urosepsis or severe hemorrhages were not seen. There were no significant associations between the assessed risk factors and biopsy-related complications. Conclusion: In-bore transrectal MRI-guided prostate biopsies can be considered safe procedures in the diagnosis of prostate cancer with very low complication rates. There seem to be no risk factors for complications.

  17. Radiofrequency hyperthermia for advanced malignant liver tumors

    International Nuclear Information System (INIS)

    Nagata, Y.; Okuno, Y.; Mitsumori, M.; Akuta, K.; Nishimura, Y.; Masunaga, S.; Kanamori, S.; Fujishiro, M.; Hiraoka, M.; Takahashi, M.; Abe, M.

    1996-01-01

    Purpose: To evaluate thermometry and the clinical results of radiofrequency (RF) thermotherapy for advanced malignant liver tumors. Materials and Methods One-hundred and seventy-three patients with malignant liver tumors treated between 1983 and 1995 underwent hyperthermia. Surgery were contraindicated in all patients. The 173 tumors consisted of 114 hepatocellular carcinomas(HCCs), and 59 non-HCCs(45 metastatic liver tumors and 12 cholangiocarcinomas). Eight MHz RF capacitive heating equipment was used for hyperthermia. Two opposing 25-cm or 30-cm electrodes were generally used for heating liver tumors. Our standard protocol was to administer hyperthermia 40-50 minutes twice a week to a total of 8 sessions. Temperature of the liver tumor was measured by microthermocouples. In each patient, a single catheter was inserted into the liver tumor through the normal liver. Transcatheter arterial embolization, radiotherapy, immunotherapy, and chemotherapy were combined with hyperthermia depending on the patient's liver function and tumor location. The therapeutic efficacy was evaluated by the change in tumor size assessed by computed tomography (CT) three or four months after the completion of treatment. Results One-hundred and forty (81%) of 173 patients underwent hyperthermia more than 4 times. Thermometry could be performed in 77(55%) of these 140 patients. Neither systolic nor diastolic blood pressure changed significantly after hyperthermia. However, pulse rate significantly increased from 82.8 ± 1.1 to 96.5 ± 1.3 beats/min. Only 21 patients (11%) showed a decrease in pulse rate after hyperthermia. Body temperature increased from 36.3 ±0.1 to 37.4±0.2 after hyperthermia. Sequelae of hyperthermia included focal fat burning in 20 (12%), gastric ulceration in 4 (2%), and liver necrosis in 1(1%). Sequelae of thermometry were severe peritoneal pain in 7 (11%), intraperitoneal hematoma in 1(1%), and pneumothorax in one (1%) patient. The maximal tumor temperature

  18. Accuracy of applicator tip reconstruction in MRI-guided interstitial 192Ir-high-dose-rate brachytherapy of liver tumors

    International Nuclear Information System (INIS)

    Wybranski, Christian; Eberhardt, Benjamin; Fischbach, Katharina; Fischbach, Frank; Walke, Mathias; Hass, Peter; Röhl, Friedrich-Wilhelm; Kosiek, Ortrud; Kaiser, Mandy; Pech, Maciej; Lüdemann, Lutz; Ricke, Jens

    2015-01-01

    Background and purpose: To evaluate the reconstruction accuracy of brachytherapy (BT) applicators tips in vitro and in vivo in MRI-guided 192 Ir-high-dose-rate (HDR)-BT of inoperable liver tumors. Materials and methods: Reconstruction accuracy of plastic BT applicators, visualized by nitinol inserts, was assessed in MRI phantom measurements and in MRI 192 Ir-HDR-BT treatment planning datasets of 45 patients employing CT co-registration and vector decomposition. Conspicuity, short-term dislocation, and reconstruction errors were assessed in the clinical data. The clinical effect of applicator reconstruction accuracy was determined in follow-up MRI data. Results: Applicator reconstruction accuracy was 1.6 ± 0.5 mm in the phantom measurements. In the clinical MRI datasets applicator conspicuity was rated good/optimal in ⩾72% of cases. 16/129 applicators showed not time dependent deviation in between MRI/CT acquisition (p > 0.1). Reconstruction accuracy was 5.5 ± 2.8 mm, and the average image co-registration error was 3.1 ± 0.9 mm. Vector decomposition revealed no preferred direction of reconstruction errors. In the follow-up data deviation of planned dose distribution and irradiation effect was 6.9 ± 3.3 mm matching the mean co-registration error (6.5 ± 2.5 mm; p > 0.1). Conclusion: Applicator reconstruction accuracy in vitro conforms to AAPM TG 56 standard. Nitinol-inserts are feasible for applicator visualization and yield good conspicuity in MRI treatment planning data. No preferred direction of reconstruction errors were found in vivo

  19. SU-C-BRA-01: Interactive Auto-Segmentation for Bowel in Online Adaptive MRI-Guided Radiation Therapy by Using a Multi-Region Labeling Algorithm

    International Nuclear Information System (INIS)

    Lu, Y; Chen, I; Kashani, R; Wan, H; Maughan, N; Muccigrosso, D; Parikh, P

    2016-01-01

    Purpose: In MRI-guided online adaptive radiation therapy, re-contouring of bowel is time-consuming and can impact the overall time of patients on table. The study aims to auto-segment bowel on volumetric MR images by using an interactive multi-region labeling algorithm. Methods: 5 Patients with locally advanced pancreatic cancer underwent fractionated radiotherapy (18–25 fractions each, total 118 fractions) on an MRI-guided radiation therapy system with a 0.35 Tesla magnet and three Co-60 sources. At each fraction, a volumetric MR image of the patient was acquired when the patient was in the treatment position. An interactive two-dimensional multi-region labeling technique based on graph cut solver was applied on several typical MRI images to segment the large bowel and small bowel, followed by a shape based contour interpolation for generating entire bowel contours along all image slices. The resulted contours were compared with the physician’s manual contouring by using metrics of Dice coefficient and Hausdorff distance. Results: Image data sets from the first 5 fractions of each patient were selected (total of 25 image data sets) for the segmentation test. The algorithm segmented the large and small bowel effectively and efficiently. All bowel segments were successfully identified, auto-contoured and matched with manual contours. The time cost by the algorithm for each image slice was within 30 seconds. For large bowel, the calculated Dice coefficients and Hausdorff distances (mean±std) were 0.77±0.07 and 13.13±5.01mm, respectively; for small bowel, the corresponding metrics were 0.73±0.08and 14.15±4.72mm, respectively. Conclusion: The preliminary results demonstrated the potential of the proposed algorithm in auto-segmenting large and small bowel on low field MRI images in MRI-guided adaptive radiation therapy. Further work will be focused on improving its segmentation accuracy and lessening human interaction.

  20. SU-C-BRA-01: Interactive Auto-Segmentation for Bowel in Online Adaptive MRI-Guided Radiation Therapy by Using a Multi-Region Labeling Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Y; Chen, I; Kashani, R; Wan, H; Maughan, N; Muccigrosso, D; Parikh, P [Washington University School of Medicine, Saint Louis, MO (United States)

    2016-06-15

    Purpose: In MRI-guided online adaptive radiation therapy, re-contouring of bowel is time-consuming and can impact the overall time of patients on table. The study aims to auto-segment bowel on volumetric MR images by using an interactive multi-region labeling algorithm. Methods: 5 Patients with locally advanced pancreatic cancer underwent fractionated radiotherapy (18–25 fractions each, total 118 fractions) on an MRI-guided radiation therapy system with a 0.35 Tesla magnet and three Co-60 sources. At each fraction, a volumetric MR image of the patient was acquired when the patient was in the treatment position. An interactive two-dimensional multi-region labeling technique based on graph cut solver was applied on several typical MRI images to segment the large bowel and small bowel, followed by a shape based contour interpolation for generating entire bowel contours along all image slices. The resulted contours were compared with the physician’s manual contouring by using metrics of Dice coefficient and Hausdorff distance. Results: Image data sets from the first 5 fractions of each patient were selected (total of 25 image data sets) for the segmentation test. The algorithm segmented the large and small bowel effectively and efficiently. All bowel segments were successfully identified, auto-contoured and matched with manual contours. The time cost by the algorithm for each image slice was within 30 seconds. For large bowel, the calculated Dice coefficients and Hausdorff distances (mean±std) were 0.77±0.07 and 13.13±5.01mm, respectively; for small bowel, the corresponding metrics were 0.73±0.08and 14.15±4.72mm, respectively. Conclusion: The preliminary results demonstrated the potential of the proposed algorithm in auto-segmenting large and small bowel on low field MRI images in MRI-guided adaptive radiation therapy. Further work will be focused on improving its segmentation accuracy and lessening human interaction.

  1. Hyperthermia, a modality in the wings

    Directory of Open Access Journals (Sweden)

    Szasz A

    2007-01-01

    Full Text Available Hyperthermia is a heat-treatment. It is widely used in various medical fields and has a well-recognized effect in oncology. Its effect is achieved by overheating of the targeted tissues. It is an ancient treatment and a promising physical approach with lack of acceptance by the serious medical use. To accept the method we need strong proofs and stable, reproducible treatment quality, but we are limited by biological, physical/technical and physiological problems. However, the main point - I believe - is the incorrect characterization and unrealistic expectations from this capable method. The temperature concept of the quality assurance guidelines has to be replaced by the heat-dose sensitive characterization, pointing the essence of the hyperthermia method.

  2. Time course of late rectal- and urinary bladder side effects after MRI-guided adaptive brachytherapy for cervical cancer

    Energy Technology Data Exchange (ETDEWEB)

    Georg, P.; Georg, D.; Poetter, R.; Doerr, W. [Medical University Vienna/ AKH Wien (Austria). Dept. of Radiooncology; Medical University Vienna (Austria). Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology; Medical University Vienna/ AKH Wien (Austria). Comprehensive Cancer Centre; Boni, A.; Ghabuous, A. [Medical University Vienna/ AKH Wien (Austria). Dept. of Radiooncology; Goldner, G.; Schmid, M.P. [Medical University Vienna/ AKH Wien (Austria). Dept. of Radiooncology; Medical University Vienna/ AKH Wien (Austria). Comprehensive Cancer Centre

    2013-07-15

    Background and purpose: To analyze the time course of late rectal- and urinary bladder complications after brachytherapy for cervical cancer and to compare the incidence- and prevalence rates thereof. Patients and methods: A total of 225 patients were treated with external-beam radiotherapy (EBRT) and magnetic resonance imaging (MRI)-guided brachytherapy with or without chemotherapy. Late side effects were assessed prospectively using the Late Effects in Normal Tissue - Subjective, Objective, Management and Analytic (LENT/SOMA) scale. The parameters analyzed were time to onset, duration, actuarial incidence- (occurrence of new side effects during a defined time period) and prevalence rates (side effects existing at a defined time point). Results: Median follow-up was 44 months. Side effects (grade 1-4) in rectum and bladder were present in 31 and 49 patients, 14 and 27 months (mean time to onset) after treatment, respectively. All rectal and 76 % of bladder side effects occurred within 3 years after radiotherapy. Mean duration of rectal events was 19 months; 81 % resolved within 3 years of their initial diagnosis. Mean duration of bladder side effects was 20 months; 61 % resolved within 3 years. The 3- and 5-year actuarial complication rates were 16 and 19 % in rectum and 18 and 28 % in bladder, respectively. The corresponding prevalence rates were 9 and 2 % (rectum) and 18 and 21 % (bladder), respectively. Conclusion: Late side effects after cervical cancer radiotherapy are partially reversible, but their time course is organ-dependent. The combined presentation of incidence- and prevalence rates provides the most comprehensive information. (orig.)

  3. Time course of late rectal- and urinary bladder side effects after MRI-guided adaptive brachytherapy for cervical cancer

    International Nuclear Information System (INIS)

    Georg, P.; Georg, D.; Poetter, R.; Doerr, W.; Medical University Vienna; Medical University Vienna/ AKH Wien; Boni, A.; Ghabuous, A.; Goldner, G.; Schmid, M.P.; Medical University Vienna/ AKH Wien

    2013-01-01

    Background and purpose: To analyze the time course of late rectal- and urinary bladder complications after brachytherapy for cervical cancer and to compare the incidence- and prevalence rates thereof. Patients and methods: A total of 225 patients were treated with external-beam radiotherapy (EBRT) and magnetic resonance imaging (MRI)-guided brachytherapy with or without chemotherapy. Late side effects were assessed prospectively using the Late Effects in Normal Tissue - Subjective, Objective, Management and Analytic (LENT/SOMA) scale. The parameters analyzed were time to onset, duration, actuarial incidence- (occurrence of new side effects during a defined time period) and prevalence rates (side effects existing at a defined time point). Results: Median follow-up was 44 months. Side effects (grade 1-4) in rectum and bladder were present in 31 and 49 patients, 14 and 27 months (mean time to onset) after treatment, respectively. All rectal and 76 % of bladder side effects occurred within 3 years after radiotherapy. Mean duration of rectal events was 19 months; 81 % resolved within 3 years of their initial diagnosis. Mean duration of bladder side effects was 20 months; 61 % resolved within 3 years. The 3- and 5-year actuarial complication rates were 16 and 19 % in rectum and 18 and 28 % in bladder, respectively. The corresponding prevalence rates were 9 and 2 % (rectum) and 18 and 21 % (bladder), respectively. Conclusion: Late side effects after cervical cancer radiotherapy are partially reversible, but their time course is organ-dependent. The combined presentation of incidence- and prevalence rates provides the most comprehensive information. (orig.)

  4. Nanotechnology in hyperthermia cancer therapy: From fundamental principles to advanced applications.

    Science.gov (United States)

    Beik, Jaber; Abed, Ziaeddin; Ghoreishi, Fatemeh S; Hosseini-Nami, Samira; Mehrzadi, Saeed; Shakeri-Zadeh, Ali; Kamrava, S Kamran

    2016-08-10

    In this work, we present an in-depth review of recent breakthroughs in nanotechnology for hyperthermia cancer therapy. Conventional hyperthermia methods do not thermally discriminate between the target and the surrounding normal tissues, and this non-selective tissue heating can lead to serious side effects. Nanotechnology is expected to have great potential to revolutionize current hyperthermia methods. To find an appropriate place in cancer treatment, all nanotechnology-based hyperthermia methods and their risks/benefits must be thoroughly understood. In this review paper, we extensively examine and compare four modern nanotechnology-based hyperthermia methods. For each method, the possible physical mechanisms of heat generation and enhancement due to the presence of nanoparticles are explained, and recent in vitro and in vivo studies are reviewed and discussed. Nano-Photo-Thermal Therapy (NPTT) and Nano-Magnetic Hyperthermia (NMH) are reviewed as the two first exciting approaches for targeted hyperthermia. The third novel hyperthermia method, Nano-Radio-Frequency Ablation (NaRFA) is discussed together with the thermal effects of novel nanoparticles in the presence of radiofrequency waves. Finally, Nano-Ultrasound Hyperthermia (NUH) is described as the fourth modern method for cancer hyperthermia. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Luminescence properties of Sm"3"+ doped YPO_4: Effect of solvent, heat-treatment, Ca"2"+/W"6"+-co-doping and its hyperthermia application

    International Nuclear Information System (INIS)

    Dutta, Dimple P.; Ningthoujam, R. S.; Tyagi, A. K.

    2012-01-01

    Sm"3"+ doped YPO_4 spherical nanoparticles are prepared by wet chemical route. Pure YPO_4 shows the tetragonal phase, which is stable up to 900 °C, whereas pure SmPO_4 shows the phase transition from hexagonal to monoclinic when heated above 800 °C. The (2-10 at.%) Sm"3"+ doped YPO_4 shows the mixture of phases of tetragonal and hexagonal, which transform to the tetragonal phase above 800 °C. Infra-red study could distinguish confined water in the pore of hexagonal phase from water present on the surface of particles. Luminescence intensities of Sm"3"+ at 564, 601 and 645 nm are weak in case of as-prepared samples because of high non-radiative rate arising from the H_2O molecules present in pores of hexagonal lattice. The intensities increase for samples heated up to 900 °C because of increase of extent of radiative rate. Luminescence lifetime increases with increase of heat-treatment up to 900 °C. When solvent of as-prepared sample was changed from the H_2O to D_2O, 5 times enhancement in luminescence intensity is observed, which can be ascribed to the lower vibration energy of D-O over H-O, which is near to Sm"3"+. When Y"3"+ and P"5"+ ions are substituted by Ca"3"+ and W"3"+ up to 3 at.%, there is an enhancement of luminescence. In order to use them as bio-labeling in drug delivery for hyperthermia applications, hybrid of Fe_3O_4@YPO_4:7Sm is prepared and heating up to 45 °C is observed under AC magnetic field.

  6. Improvement of the matching speed of AIMS for development of an automatic totally tuning system for hyperthermia treatment using a resonant cavity applicator.

    Science.gov (United States)

    Shindo, Y; Kato, K; Tsuchiya, K; Hirashima, T; Suzuki, M

    2009-01-01

    In this paper, we discuss the improvement of the speed of AIMS (Automatic Impedance Matching System) to automatically make impedance matching for a re-entrant resonant cavity applicator for non-invasive deep brain tumors hyperthermia treatments. We have already discussed the effectiveness of the heating method using the AIMS, with experiments of heating agar phantoms. However, the operating time of AIMS was about 30 minutes. To develop the ATT System (Automatic Totally Tuning System) including the automatic frequency tuning system, we must improve this problem. Because, when using the ATTS, the AIMS is used repeatedly to find the resonant frequency. In order to improve the speed of impedance matching, we developed the new automatic impedance matching system program (AIMS2). In AIMS, the stepping motors were connected to the impedance matching unit's dials. These dials were turned to reduce the reflected power. AIMS consists of two phases: all range searching and detailed searching. We focused on the three factors affecting the operating speed and improved them. The first factor is the interval put between the turning of the motors and AD converter. The second factor is how the steps of the motor when operating all range searching. The third factor is the starting position of the motor when detail searching. We developed the simple ATT System (ATT-beta) based on the AIMS2. To evaluate the developed AIMS2 and ATT- beta, experiments with an agar phantom were performed. From these results, we found that the operating time of the AIMS2 is about 4 minutes, which was approximately 12% of AIMS. From ATT-beta results, it was shown that it is possible to tune frequency and automatically match impedance with the program based on the AIMS2.

  7. The relevance of MRI for patient modeling in head and neck hyperthermia treatment planning: A comparison of CT and CT-MRI based tissue segmentation on simulated temperature

    International Nuclear Information System (INIS)

    Verhaart, René F.; Paulides, Margarethus M.; Fortunati, Valerio; Walsum, Theo van; Veenland, Jifke F.; Verduijn, Gerda M.; Lugt, Aad van der

    2014-01-01

    Purpose: In current clinical practice, head and neck (H and N) hyperthermia treatment planning (HTP) is solely based on computed tomography (CT) images. Magnetic resonance imaging (MRI) provides superior soft-tissue contrast over CT. The purpose of the authors’ study is to investigate the relevance of using MRI in addition to CT for patient modeling in H and N HTP. Methods: CT and MRI scans were acquired for 11 patients in an immobilization mask. Three observers manually segmented on CT, MRI T1 weighted (MRI-T1w), and MRI T2 weighted (MRI-T2w) images the following thermo-sensitive tissues: cerebrum, cerebellum, brainstem, myelum, sclera, lens, vitreous humor, and the optical nerve. For these tissues that are used for patient modeling in H and N HTP, the interobserver variation of manual tissue segmentation in CT and MRI was quantified with the mean surface distance (MSD). Next, the authors compared the impact of CT and CT and MRI based patient models on the predicted temperatures. For each tissue, the modality was selected that led to the lowest observer variation and inserted this in the combined CT and MRI based patient model (CT and MRI), after a deformable image registration. In addition, a patient model with a detailed segmentation of brain tissues (including white matter, gray matter, and cerebrospinal fluid) was created (CT and MRI db ). To quantify the relevance of MRI based segmentation for H and N HTP, the authors compared the predicted maximum temperatures in the segmented tissues (T max ) and the corresponding specific absorption rate (SAR) of the patient models based on (1) CT, (2) CT and MRI, and (3) CT and MRI db . Results: In MRI, a similar or reduced interobserver variation was found compared to CT (maximum of median MSD in CT: 0.93 mm, MRI-T1w: 0.72 mm, MRI-T2w: 0.66 mm). Only for the optical nerve the interobserver variation is significantly lower in CT compared to MRI (median MSD in CT: 0.58 mm, MRI-T1w: 1.27 mm, MRI-T2w: 1.40 mm). Patient

  8. The relevance of MRI for patient modeling in head and neck hyperthermia treatment planning: A comparison of CT and CT-MRI based tissue segmentation on simulated temperature

    Energy Technology Data Exchange (ETDEWEB)

    Verhaart, René F., E-mail: r.f.verhaart@erasmusmc.nl; Paulides, Margarethus M. [Hyperthermia Unit, Department of Radiation Oncology, Erasmus MC - Cancer Institute, Groene Hilledijk 301, Rotterdam 3008 AE (Netherlands); Fortunati, Valerio; Walsum, Theo van; Veenland, Jifke F. [Biomedical Imaging Group of Rotterdam, Department of Medical Informatics and Radiology, Erasmus MC, Dr. Molewaterplein 50/60, Rotterdam 3015 GE (Netherlands); Verduijn, Gerda M. [Department of Radiation Oncology, Erasmus MC - Cancer Institute, Groene Hilledijk 301, Rotterdam 3008 AE (Netherlands); Lugt, Aad van der [Department of Radiology, Erasmus MC, Dr. Molewaterplein 50/60, Rotterdam 3015 GE (Netherlands)

    2014-12-15

    Purpose: In current clinical practice, head and neck (H and N) hyperthermia treatment planning (HTP) is solely based on computed tomography (CT) images. Magnetic resonance imaging (MRI) provides superior soft-tissue contrast over CT. The purpose of the authors’ study is to investigate the relevance of using MRI in addition to CT for patient modeling in H and N HTP. Methods: CT and MRI scans were acquired for 11 patients in an immobilization mask. Three observers manually segmented on CT, MRI T1 weighted (MRI-T1w), and MRI T2 weighted (MRI-T2w) images the following thermo-sensitive tissues: cerebrum, cerebellum, brainstem, myelum, sclera, lens, vitreous humor, and the optical nerve. For these tissues that are used for patient modeling in H and N HTP, the interobserver variation of manual tissue segmentation in CT and MRI was quantified with the mean surface distance (MSD). Next, the authors compared the impact of CT and CT and MRI based patient models on the predicted temperatures. For each tissue, the modality was selected that led to the lowest observer variation and inserted this in the combined CT and MRI based patient model (CT and MRI), after a deformable image registration. In addition, a patient model with a detailed segmentation of brain tissues (including white matter, gray matter, and cerebrospinal fluid) was created (CT and MRI{sub db}). To quantify the relevance of MRI based segmentation for H and N HTP, the authors compared the predicted maximum temperatures in the segmented tissues (T{sub max}) and the corresponding specific absorption rate (SAR) of the patient models based on (1) CT, (2) CT and MRI, and (3) CT and MRI{sub db}. Results: In MRI, a similar or reduced interobserver variation was found compared to CT (maximum of median MSD in CT: 0.93 mm, MRI-T1w: 0.72 mm, MRI-T2w: 0.66 mm). Only for the optical nerve the interobserver variation is significantly lower in CT compared to MRI (median MSD in CT: 0.58 mm, MRI-T1w: 1.27 mm, MRI-T2w: 1.40 mm

  9. The relevance of MRI for patient modeling in head and neck hyperthermia treatment planning: a comparison of CT and CT-MRI based tissue segmentation on simulated temperature.

    Science.gov (United States)

    Verhaart, René F; Fortunati, Valerio; Verduijn, Gerda M; van der Lugt, Aad; van Walsum, Theo; Veenland, Jifke F; Paulides, Margarethus M

    2014-12-01

    In current clinical practice, head and neck (H&N) hyperthermia treatment planning (HTP) is solely based on computed tomography (CT) images. Magnetic resonance imaging (MRI) provides superior soft-tissue contrast over CT. The purpose of the authors' study is to investigate the relevance of using MRI in addition to CT for patient modeling in H&N HTP. CT and MRI scans were acquired for 11 patients in an immobilization mask. Three observers manually segmented on CT, MRI T1 weighted (MRI-T1w), and MRI T2 weighted (MRI-T2w) images the following thermo-sensitive tissues: cerebrum, cerebellum, brainstem, myelum, sclera, lens, vitreous humor, and the optical nerve. For these tissues that are used for patient modeling in H&N HTP, the interobserver variation of manual tissue segmentation in CT and MRI was quantified with the mean surface distance (MSD). Next, the authors compared the impact of CT and CT and MRI based patient models on the predicted temperatures. For each tissue, the modality was selected that led to the lowest observer variation and inserted this in the combined CT and MRI based patient model (CT and MRI), after a deformable image registration. In addition, a patient model with a detailed segmentation of brain tissues (including white matter, gray matter, and cerebrospinal fluid) was created (CT and MRIdb). To quantify the relevance of MRI based segmentation for H&N HTP, the authors compared the predicted maximum temperatures in the segmented tissues (Tmax) and the corresponding specific absorption rate (SAR) of the patient models based on (1) CT, (2) CT and MRI, and (3) CT and MRIdb. In MRI, a similar or reduced interobserver variation was found compared to CT (maximum of median MSD in CT: 0.93 mm, MRI-T1w: 0.72 mm, MRI-T2w: 0.66 mm). Only for the optical nerve the interobserver variation is significantly lower in CT compared to MRI (median MSD in CT: 0.58 mm, MRI-T1w: 1.27 mm, MRI-T2w: 1.40 mm). Patient models based on CT (Tmax: 38.0 °C) and CT and MRI

  10. Investigation properties of superparamagnetic nanoparticles and magnetic field-dependent hyperthermia therapy

    Science.gov (United States)

    Hedayatnasab, Z.; Abnisa, F.; Daud, W. M. A. Wan

    2018-03-01

    The application of superparamagnetic nanoparticles as heating agents in hyperthermia therapy has made a therapeutic breakthrough in cancer treatment. The high efficiency of this magnetic hyperthermia therapy has derived from a great capability of superparamagnetic nanoparticles to generate focused heat in inaccessible tumors being effectively inactivated. The main challenges of this therapy are the improvement of the induction heating power of superparamagnetic nanoparticles and the control of the hyperthermia temperature in a secure range of 42 °C to 47 °C, at targeted area. The variation of these hyperthermia properties is principally dependent on the magnetic nanoparticles as well as the magnetic field leading to enhance the efficiency of magnetic hyperthermia therapy at targeted area and also avoid undue heating to healthy cells. The present study evaluates the magnetic hyperthermia therapy through the determination of superparamagnetic nanoparticles properties and magnetic field’ parameters.

  11. Effects of Radiofrequency Induced local Hyperthermia on Normal Canine Liver

    International Nuclear Information System (INIS)

    Suh, Chang Ok; Loh, John J. K.; Seong, Jin Sil

    1991-01-01

    In order to assess the effects of radiofrequency-induced local hyperthermia on the normal liver, histopathologic findings and biochemical changes after localized hyperthermia in canine liver were studied. Hyperthermia was externally administered using the Thermotron RF-8 (Yamamoto Vinyter Co., Japan; Capacitive type heating machine) with parallel opposed electrodes. Thirteen dogs were used and allocated into one control group (N=3) and two treatment groups according to the treatment temperature. Group I (N=5) was heated with 42.5±0.5.deg.C for 30 minutes, and Group(N=5) was heated with 45±0.5.deg.C for 15-30 minutes. Samples of liver tissue were obtained through a needle biopsy immediately after hyperthermia and 7, 14 and 28 days after treatment and examined for SGOT, SGPT and alkaline phosphatase. Although SGOT and SGPT were elevated after hyperthermia in both groups (three of five in each group), there was no liver cell necrosis or hyperthermia related mortality in Group I. A hydropic swelling of hepatocytes was prominent histologic finding. Hyperthermia with 45.deg.C for 30 minutes was fatal and showed extensive liver cell necrosis. In conclusion, liver damage day heat of 42.5±0.5.deg.C for 30 minutes is reversible, and liver damage by heat of 45±0.5.deg.C for 30 minutes can be fatal or irreversible. However, these results cannot be applied directly to human trial. Therefore, in order to apply hyperthermic treatment on human liver tumor safely, close observation of temperature with proper thermometry is mandatory. Hyperthermic treatment should be confined to the tumor area while sparing a normal liver as much as possible

  12. TU-EF-210-02: MRg Hyperthermia

    International Nuclear Information System (INIS)

    Chopra, R.

    2015-01-01

    The use of therapeutic ultrasound to provide targeted therapy is an active research area that has a broad application scope. The invited talks in this session will address currently implemented strategies and protocols for both hyperthermia and ablation applications using therapeutic ultrasound. The role of both ultrasound and MRI in the monitoring and assessment of these therapies will be explored in both pre-clinical and clinical applications. Katherine Ferrara: High Intensity Focused Ultrasound, Drug Delivery, and Immunotherapy Rajiv Chopra: Translating Localized Doxorubicin Delivery to Pediatric Oncology using MRI-guided HIFU Elisa Konofagou: Real-time Ablation Monitoring and Lesion Quantification using Harmonic Motion Imaging Keyvan Farahani: AAPM Task Groups in Interventional Ultrasound Imaging and Therapy Learning Objectives: Understand the role of ultrasound in localized drug delivery and the effects of immunotherapy when used in conjunction with ultrasound therapy. Understand potential targeted drug delivery clinical applications including pediatric oncology. Understand the technical requirements for performing targeted drug delivery. Understand how radiation-force approaches can be used to both monitor and assess high intensity focused ultrasound ablation therapy. Understand the role of AAPM task groups in ultrasound imaging and therapies. Chopra: Funding from Cancer Prevention and Research Initiative of Texas (CPRIT), Award R1308 Evelyn and M.R. Hudson Foundation; Research Support from Research Contract with Philips Healthcare; COI are Co-founder of FUS Instruments Inc Ferrara: Supported by NIH, UCDavis and California (CIRM and BHCE) Farahani: In-kind research support from Philips Healthcare

  13. TU-EF-210-02: MRg Hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, R. [UT Southwestern Medical Ctr at Dallas (United States)

    2015-06-15

    The use of therapeutic ultrasound to provide targeted therapy is an active research area that has a broad application scope. The invited talks in this session will address currently implemented strategies and protocols for both hyperthermia and ablation applications using therapeutic ultrasound. The role of both ultrasound and MRI in the monitoring and assessment of these therapies will be explored in both pre-clinical and clinical applications. Katherine Ferrara: High Intensity Focused Ultrasound, Drug Delivery, and Immunotherapy Rajiv Chopra: Translating Localized Doxorubicin Delivery to Pediatric Oncology using MRI-guided HIFU Elisa Konofagou: Real-time Ablation Monitoring and Lesion Quantification using Harmonic Motion Imaging Keyvan Farahani: AAPM Task Groups in Interventional Ultrasound Imaging and Therapy Learning Objectives: Understand the role of ultrasound in localized drug delivery and the effects of immunotherapy when used in conjunction with ultrasound therapy. Understand potential targeted drug delivery clinical applications including pediatric oncology. Understand the technical requirements for performing targeted drug delivery. Understand how radiation-force approaches can be used to both monitor and assess high intensity focused ultrasound ablation therapy. Understand the role of AAPM task groups in ultrasound imaging and therapies. Chopra: Funding from Cancer Prevention and Research Initiative of Texas (CPRIT), Award R1308 Evelyn and M.R. Hudson Foundation; Research Support from Research Contract with Philips Healthcare; COI are Co-founder of FUS Instruments Inc Ferrara: Supported by NIH, UCDavis and California (CIRM and BHCE) Farahani: In-kind research support from Philips Healthcare.

  14. Atlas-based deformable image registration for MRI-guided prostate radiation therapy

    International Nuclear Information System (INIS)

    Dowling, J.; Fripp, J.; Salvado, O.; Lambert, J.; Denham, J.W.; Capp, A.; Grer, P.B.; Parker, J.

    2010-01-01

    Full text: To develop atlas-based deformable image registration methods to automatically segment organs and map electron densities to pelvic MRI scans for MRI-guided radiation therapy. Methods An MRT pelvic atlas and corresponding CT atlas were developed based on whole pelvic T 2 MRI scans and CT scans for 39 patients. Expert manual segmentations on both MRI and CT scans were obtained. The atlas was deformably registered to the individual patient MRI scans for automatic prostate, rectum, bladder and bone segmentation. These were compared to the manual segmentations using the Dice overlap coefficient. The same deformation vectors were then applied to the CT-atlas to produce pseudo-CT scans that correspond to the patient MRI scan anatomy but are populated with Hounsfield units. The original patient plan was recalculated on the pseudo-CT and compared to the original CT plan and bulk density plans on the MRI scans. Results Dice coefficient results were high (>0.8) for bone and prostate but lower (<0.7) for bladder and rectum which exhibit greater changes in shape and volume. Doses calculated on pseudo-CT scans were within 3% of original patient plans. Two sources of discrepancy were found; MR anatomy differences from CT due to patient setup differences at the MR scanner. and Hounsfield unit differences for bone in the pseudo-CT from original CT. Patient setup will be adressed with a

  15. MRI-guided focused ultrasound thalamotomy in non-ET tremor syndromes.

    Science.gov (United States)

    Fasano, Alfonso; Llinas, Maheleth; Munhoz, Renato P; Hlasny, Eugen; Kucharczyk, Walter; Lozano, Andres M

    2017-08-22

    To report the 6-month single-blinded results of unilateral thalamotomy with MRI-guided focused ultrasound (MRgFUS) in patients with tremors other than essential tremor. Three patients with tremor due to Parkinson disease, 2 with dystonic tremor in the context of cervicobrachial dystonia and writer's cramp, and 1 with dystonia gene-associated tremor underwent MRgFUS targeting the ventro-intermedius nucleus (Vim) of the dominant hemisphere. The primary endpoint was the reduction of lateralized items of the Tremor Rating Scale of contralateral hemibody assessed by a blinded rater. All patients achieved a statistically significant, immediate, and sustained improvement of the contralateral tremor score by 42.2%, 52.0%, 55.9%, and 52.9% at 1 week and 1, 3, and 6 months after the procedure, respectively. All patients experienced transient side effects and 2 patients experienced persistent side effects at the time of last evaluation: hemitongue numbness and hemiparesis with hemihypoesthesia. Vim MRgFUS is a promising, incision-free, but nevertheless invasive technique to effectively treat tremors other than essential tremor. Future studies on larger samples and longer follow-up will further define its effectiveness and safety. NCT02252380. This study provides Class IV evidence that for patients with tremor not caused by essential tremor, MRgFUS of the Vim improves the tremor of the contralateral hemibody at 6 months. © 2017 American Academy of Neurology.

  16. Positioning device for MRI-guided high intensity focused ultrasound system

    Energy Technology Data Exchange (ETDEWEB)

    Damianou, Christakis [Frederick Institute of Technology (FIT), Limassol (Cyprus); MEDSONIC, LTD, Limassol (Cyprus); Ioannides, Kleanthis [Polikliniki Igia, Limassol (Cyprus); Milonas, Nicos [Frederick Institute of Technology (FIT), Limassol (Cyprus)

    2008-04-15

    A prototype magnetic resonance imaging (MRI)- compatible positioning device was used to move an MRI-guided high intensity focused ultrasound (HIFU) transducer. The positioning device has three user-controlled degrees of freedom that allow access to various targeted lesions. The positioning device was designed and fabricated using construction materials selected for compatibility with high magnetic fields and fast switching magnetic field gradients encountered inside MRI scanners. The positioning device incorporates only MRI compatible materials such as piezoelectric motors, plastic sheets, brass screws, plastic pulleys and timing belts. The HIFU/MRI system includes the multiple subsystems (a) HIFU system, (b) MR imaging, (c) Positioning device (robot) and associate drivers, (d) temperature measurement, (e) cavitation detection, (f) MRI compatible camera, and (g) Soft ware. The MRI compatibility of the system was successfully demonstrated in a clinical high-field MRI scanner. The ability of the robot to accurately move the transducer thus creating discrete and overlapping lesions in biological tissue was tested successfully. A simple, cost effective, portable positioning device has been developed which can be used in virtually any clinical MRI scanner since it can be sited on the scanner's table. The propagation of HIFU can use either a lateral or superior-inferior approach. Discrete and large lesions were created successfully with reproducible results. (orig.)

  17. Piezoelectrically Actuated Robotic System for MRI-Guided Prostate Percutaneous Therapy

    Science.gov (United States)

    Su, Hao; Shang, Weijian; Cole, Gregory; Li, Gang; Harrington, Kevin; Camilo, Alexander; Tokuda, Junichi; Tempany, Clare M.; Hata, Nobuhiko; Fischer, Gregory S.

    2014-01-01

    This paper presents a fully-actuated robotic system for percutaneous prostate therapy under continuously acquired live magnetic resonance imaging (MRI) guidance. The system is composed of modular hardware and software to support the surgical workflow of intra-operative MRI-guided surgical procedures. We present the development of a 6-degree-of-freedom (DOF) needle placement robot for transperineal prostate interventions. The robot consists of a 3-DOF needle driver module and a 3-DOF Cartesian motion module. The needle driver provides needle cannula translation and rotation (2-DOF) and stylet translation (1-DOF). A custom robot controller consisting of multiple piezoelectric motor drivers provides precision closed-loop control of piezoelectric motors and enables simultaneous robot motion and MR imaging. The developed modular robot control interface software performs image-based registration, kinematics calculation, and exchanges robot commands and coordinates between the navigation software and the robot controller with a new implementation of the open network communication protocol OpenIGTLink. Comprehensive compatibility of the robot is evaluated inside a 3-Tesla MRI scanner using standard imaging sequences and the signal-to-noise ratio (SNR) loss is limited to 15%. The image deterioration due to the present and motion of robot demonstrates unobservable image interference. Twenty-five targeted needle placements inside gelatin phantoms utilizing an 18-gauge ceramic needle demonstrated 0.87 mm root mean square (RMS) error in 3D Euclidean distance based on MRI volume segmentation of the image-guided robotic needle placement procedure. PMID:26412962

  18. TU-AB-202-06: Quantitative Evaluation of Deformable Image Registration in MRI-Guided Adaptive Radiation Therapy

    International Nuclear Information System (INIS)

    Mooney, K; Zhao, T; Green, O; Mutic, S; Yang, D; Duan, Y; Zhang, M

    2016-01-01

    Purpose: To assess the performance of the deformable image registration algorithm used for MRI-guided adaptive radiation therapy using image feature analysis. Methods: MR images were collected from five patients treated on the MRIdian (ViewRay, Inc., Oakwood Village, OH), a three head Cobalt-60 therapy machine with an 0.35 T MR system. The images were acquired immediately prior to treatment with a uniform 1.5 mm resolution. Treatment sites were as follows: head/neck, lung, breast, stomach, and bladder. Deformable image registration was performed using the ViewRay software between the first fraction MRI and the final fraction MRI, and the DICE similarity coefficient (DSC) for the skin contours was reported. The SIFT and Harris feature detection and matching algorithms identified point features in each image separately, then found matching features in the other image. The target registration error (TRE) was defined as the vector distance between matched features on the two image sets. Each deformation was evaluated based on comparison of average TRE and DSC. Results: Image feature analysis produced between 2000–9500 points for evaluation on the patient images. The average (± standard deviation) TRE for all patients was 3.3 mm (±3.1 mm), and the passing rate of TRE<3 mm was 60% on the images. The head/neck patient had the best average TRE (1.9 mm±2.3 mm) and the best passing rate (80%). The lung patient had the worst average TRE (4.8 mm±3.3 mm) and the worst passing rate (37.2%). DSC was not significantly correlated with either TRE (p=0.63) or passing rate (p=0.55). Conclusions: Feature matching provides a quantitative assessment of deformable image registration, with a large number of data points for analysis. The TRE of matched features can be used to evaluate the registration of many objects throughout the volume, whereas DSC mainly provides a measure of gross overlap. We have a research agreement with ViewRay Inc.

  19. SU-G-JeP2-03: Automatic Quantification of MLC Positional Accuracy in An MRI Guided Radiotherapy System

    International Nuclear Information System (INIS)

    Li, X; Studenski, M; Yang, F; Dogan, N; Lamichhane, N; Padgett, K

    2016-01-01

    Purpose: MRI-guided-radiotherapy (MRIGRT) systems lack many features of traditional Linac based RT systems and specialized tests need to be developed to evaluate MLC performance. This work describes automatic tools for the analysis of positional accuracy of an MLC equipped MRIGRT system. Methods: This MLC analysis tool was developed for the MRIdian™ RT system which has three Co-60 equipped treatment heads each with a double focused MLC containing 30 leaf pairs, leaf thickness is 1.05cm defined at isocenter (SAD 105 cm). For MLC positional analysis a picket fence test was performed using a 25.4cm × 25.4cm Gafchromic™ RTQA2 film placed between 5cm solidwater and a 30cm × 30cm × 1cm jigwire phantom with seven embedded parallel metal strips 4cm apart. A plan was generated to deliver 2Gy per field and seven 23.1cm × 2cm fields centered over each wire in the phantom. For each leaf pair the center of the radiation profile was determined by fitting the horizontal profile with a Gaussian model and determining the center of the FWHM. This was compared with the metal strip location to determine any deviation. The following metrics were used to evaluate the deviations per gantry angle including maximum, minimum, mean, Kurtosis, and skewness. Results: The identified maximum/mean leaf deviations are, 1.32/0.55 mm for gantry 0°, 1.59/0.76 mm for gantry 90°, and 1.19/0.39 mm for gantry 270°. The percentage of leaf deviation less than 1mm are 90.0% at 0°, 74.6% at 90°, and 97.0% at 270°. Kurtosis/skewness of the leaf deviation are 2.41/0.14 at 0°, 2.53/0.23 at 90°, 3.33/0.83 at 270°, respectively. Conclusion: This work presents an automatic tool for evaluation of the MLC position accuracy of the MRIdian™ radiotherapy system which can be used to benchmark the performance of the MLC system for each treatment head and track the results longitudinally.

  20. TU-AB-202-06: Quantitative Evaluation of Deformable Image Registration in MRI-Guided Adaptive Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Mooney, K; Zhao, T; Green, O; Mutic, S; Yang, D [Washington University School of Medicine, Saint Louis, MO (United States); Duan, Y [University of Missouri, Columbia, Missouri (United States); Zhang, M [Oregon Health and Science University, Portland, Oregon (United States)

    2016-06-15

    Purpose: To assess the performance of the deformable image registration algorithm used for MRI-guided adaptive radiation therapy using image feature analysis. Methods: MR images were collected from five patients treated on the MRIdian (ViewRay, Inc., Oakwood Village, OH), a three head Cobalt-60 therapy machine with an 0.35 T MR system. The images were acquired immediately prior to treatment with a uniform 1.5 mm resolution. Treatment sites were as follows: head/neck, lung, breast, stomach, and bladder. Deformable image registration was performed using the ViewRay software between the first fraction MRI and the final fraction MRI, and the DICE similarity coefficient (DSC) for the skin contours was reported. The SIFT and Harris feature detection and matching algorithms identified point features in each image separately, then found matching features in the other image. The target registration error (TRE) was defined as the vector distance between matched features on the two image sets. Each deformation was evaluated based on comparison of average TRE and DSC. Results: Image feature analysis produced between 2000–9500 points for evaluation on the patient images. The average (± standard deviation) TRE for all patients was 3.3 mm (±3.1 mm), and the passing rate of TRE<3 mm was 60% on the images. The head/neck patient had the best average TRE (1.9 mm±2.3 mm) and the best passing rate (80%). The lung patient had the worst average TRE (4.8 mm±3.3 mm) and the worst passing rate (37.2%). DSC was not significantly correlated with either TRE (p=0.63) or passing rate (p=0.55). Conclusions: Feature matching provides a quantitative assessment of deformable image registration, with a large number of data points for analysis. The TRE of matched features can be used to evaluate the registration of many objects throughout the volume, whereas DSC mainly provides a measure of gross overlap. We have a research agreement with ViewRay Inc.

  1. Radiotherapy and local hyperthermia plus androgen suppression in locally advanced prostate cancer

    International Nuclear Information System (INIS)

    Maluta, S.; Marciai, N.; Gabbani, M.; Palazzi, M.; Dall'Oglio, S.; Grandinetti, A.

    2005-01-01

    Full text: In advanced prostatic cancer, hyperthermia may be useful in order to enhance irradiation efficacy so to avoid delivering of too high dose of radiotherapy which increases acute and late sequelae. A multi-centric phase II study is warranted to give hyperthermia a level 3 evidence in prostate cancer treatment. A randomized phase III study to demonstrate efficacy of hyperthermia is not available because of the optimal results obtained by using radiotherapy combined with androgen suppression. To evaluate hyperthermia gain, LHT should be combined with radiotherapy alone in patients refusing androgen suppression or affected by hormone refractory prostate carcinoma (HRPC). Patients with HRPC have multiple possibilities of treatment improving performance status and median survival, as chemotherapy regimens, and new agents. All these treatments modalities need to be confirmed by phase III trials. Also hyperthermia may be considered among these promising approaches. (author)

  2. Imaging and modification of the tumor vascular barrier for improvement in magnetic nanoparticle uptake and hyperthermia treatment efficacy

    Science.gov (United States)

    Hoopes, P. Jack; Petryk, Alicia A.; Tate, Jennifer A.; Savellano, Mark S.; Strawbridge, Rendall R.; Giustini, Andrew J.; Stan, Radu V.; Gimi, Barjor; Garwood, Michael

    2013-02-01

    The predicted success of nanoparticle based cancer therapy is due in part to the presence of the inherent leakiness of the tumor vascular barrier, the so called enhanced permeability and retention (EPR) effect. Although the EPR effect is present in varying degrees in many tumors, it has not resulted in the consistent level of nanoparticle-tumor uptake enhancement that was initially predicted. Magnetic/iron oxide nanoparticles (mNPs) have many positive qualities, including their inert/nontoxic nature, the ability to be produced in various sizes, the ability to be activated by a deeply penetrating and nontoxic magnetic field resulting in cell-specific cytotoxic heating, and the ability to be successfully coated with a wide variety of functional coatings. However, at this time, the delivery of adequate numbers of nanoparticles to the tumor site via systemic administration remains challenging. Ionizing radiation, cisplatinum chemotherapy, external static magnetic fields and vascular disrupting agents are being used to modify the tumor environment/vasculature barrier to improve mNP uptake in tumors and subsequently tumor treatment. Preliminary studies suggest use of these modalities, individually, can result in mNP uptake improvements in the 3-10 fold range. Ongoing studies show promise of even greater tumor uptake enhancement when these methods are combined. The level and location of mNP/Fe in blood and normal/tumor tissue is assessed via histopathological methods (confocal, light and electron microscopy, histochemical iron staining, fluorescent labeling, TEM) and ICP-MS. In order to accurately plan and assess mNP-based therapies in clinical patients, a noninvasive and quantitative imaging technique for the assessment of mNP uptake and biodistribution will be necessary. To address this issue, we examined the use of computed tomography (CT), magnetic resonance imaging (MRI), and Sweep Imaging With Fourier Transformation (SWIFT), an MRI technique which provides a

  3. FDTD analysis of a noninvasive hyperthermia system for brain tumors.

    Science.gov (United States)

    Yacoob, Sulafa M; Hassan, Noha S

    2012-08-14

    Hyperthermia is considered one of the new therapeutic modalities for cancer treatment and is based on the difference in thermal sensitivity between healthy tissues and tumors. During hyperthermia treatment, the temperature of the tumor is raised to 40-45°C for a definite period resulting in the destruction of cancer cells. This paper investigates design, modeling and simulation of a new non-invasive hyperthermia applicator system capable of effectively heating deep seated as well as superficial brain tumors using inexpensive, simple, and easy to fabricate components without harming surrounding healthy brain tissues. The proposed hyperthermia applicator system is composed of an air filled partial half ellipsoidal chamber, a patch antenna, and a head model with an embedded tumor at an arbitrary location. The irradiating antenna is placed at one of the foci of the hyperthermia chamber while the center of the brain tumor is placed at the other focus. The finite difference time domain (FDTD) method is used to compute both the SAR patterns and the temperature distribution in three different head models due to two different patch antennas at a frequency of 915 MHz. The obtained results suggest that by using the proposed noninvasive hyperthermia system it is feasible to achieve sufficient and focused energy deposition and temperature rise to therapeutic values in deep seated as well as superficial brain tumors without harming surrounding healthy tissue. The proposed noninvasive hyperthermia system proved suitable for raising the temperature in tumors embedded in the brain to therapeutic values by carefully selecting the systems components. The operator of the system only needs to place the center of the brain tumor at a pre-specified location and excite the antenna at a single frequency of 915 MHz. Our study may provide a basis for a clinical applicator prototype capable of heating brain tumors.

  4. FDTD analysis of a noninvasive hyperthermia system for brain tumors

    Directory of Open Access Journals (Sweden)

    Yacoob Sulafa M

    2012-08-01

    Full Text Available Abstract Background Hyperthermia is considered one of the new therapeutic modalities for cancer treatment and is based on the difference in thermal sensitivity between healthy tissues and tumors. During hyperthermia treatment, the temperature of the tumor is raised to 40–45°C for a definite period resulting in the destruction of cancer cells. This paper investigates design, modeling and simulation of a new non-invasive hyperthermia applicator system capable of effectively heating deep seated as well as superficial brain tumors using inexpensive, simple, and easy to fabricate components without harming surrounding healthy brain tissues. Methods The proposed hyperthermia applicator system is composed of an air filled partial half ellipsoidal chamber, a patch antenna, and a head model with an embedded tumor at an arbitrary location. The irradiating antenna is placed at one of the foci of the hyperthermia chamber while the center of the brain tumor is placed at the other focus. The finite difference time domain (FDTD method is used to compute both the SAR patterns and the temperature distribution in three different head models due to two different patch antennas at a frequency of 915 MHz. Results The obtained results suggest that by using the proposed noninvasive hyperthermia system it is feasible to achieve sufficient and focused energy deposition and temperature rise to therapeutic values in deep seated as well as superficial brain tumors without harming surrounding healthy tissue. Conclusions The proposed noninvasive hyperthermia system proved suitable for raising the temperature in tumors embedded in the brain to therapeutic values by carefully selecting the systems components. The operator of the system only needs to place the center of the brain tumor at a pre-specified location and excite the antenna at a single frequency of 915 MHz. Our study may provide a basis for a clinical applicator prototype capable of heating brain tumors.

  5. Magnetic hyperthermia with hard-magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Kashevsky, Bronislav E., E-mail: bekas@itmo.by [A.V Luikov Heat and Mass Transfer Institute, Belarus Academy of Sciences, P. Brovka str. 15, Minsk 220072 (Belarus); Kashevsky, Sergey B.; Korenkov, Victor S. [A.V Luikov Heat and Mass Transfer Institute, Belarus Academy of Sciences, P. Brovka str. 15, Minsk 220072 (Belarus); Istomin, Yuri P. [N. N. Alexandrov National Cancer Center of Belarus, Lesnoy-2, Minsk 223040 (Belarus); Terpinskaya, Tatyana I.; Ulashchik, Vladimir S. [Institute of Physiology, Belarus Academy of Sciences, Akademicheskaya str. 28, Minsk 220072 (Belarus)

    2015-04-15

    Recent clinical trials of magnetic hyperthermia have proved, and even hardened, the Ankinson-Brezovich restriction as upon magnetic field conditions applicable to any site of human body. Subject to this restriction, which is harshly violated in numerous laboratory and small animal studies, magnetic hyperthermia can relay on rather moderate heat source, so that optimization of the whole hyperthermia system remains, after all, the basic problem predetermining its clinical perspectives. We present short account of our complex (theoretical, laboratory and small animal) studies to demonstrate that such perspectives should be related with the hyperthermia system based on hard-magnetic (Stoner–Wohlfarth type) nanoparticles and strong low-frequency fields rather than with superparamagnetic (Brownian or Neél) nanoparticles and weak high-frequency fields. This conclusion is backed by an analytical evaluation of the maximum absorption rates possible under the field restriction in the ideal hard-magnetic (Stoner–Wohlarth) and the ideal superparamagnetic (single relaxation time) systems, by theoretical and experimental studies of the dynamic magnetic hysteresis in suspensions of movable hard-magnetic particles, by producing nanoparticles with adjusted coercivity and suspensions of such particles capable of effective energy absorption and intratumoral penetration, and finally, by successful treatment of a mice model tumor under field conditions acceptable for whole human body. - Highlights: • Hard-magnetic nanoparticles are shown superior for hyperthetmia to superparamagnetic. • Optimal system parameters are found from magnetic reversal model in movable particle. • Penetrating suspension of HM particles with aggregation-independent SAR is developed. • For the first time, mice with tumors are healed in AC field acceptable for human body.

  6. Outcomes after environmental hyperthermia.

    Science.gov (United States)

    LoVecchio, Frank; Pizon, Anthony F; Berrett, Christopher; Balls, Adam

    2007-05-01

    This study was conducted to describe the characteristics and outcomes of patients who presented to the emergency department (ED) with presumed environmental hyperthermia. A retrospective chart review was performed in 2 institutions with patients who were seen in the ED and had a discharge diagnosis of hyperthermia, heat stroke, heat exhaustion, or heat cramps. Exclusion criteria were an alternative diagnosis potentially explaining the hyperthermia (pneumonia, etc). Research assistants, who were blinded to the purpose of the study, performed a systematic chart review after a structured training session. If necessary, a third reviewer acted as a tiebreaker. Data regarding patient demographics, comorbidities, vital signs, laboratory results, and short-term outcome were collected. Data were analyzed with Excel and STATA software. We enrolled 52 patients with a mean age of 42.6 years (range, 0.4-81 years) from August 1, 2003 to August 31, 2005. The mean high daily temperature was 103.6 degrees F (range, 88-118 degrees F). At presentation, the mean body temperature was 105.1 degrees F (range, 100.2-111.2 degrees F) and the Glasgow Coma Scale score was less than 14 in 36 (69.2%) patients. Laboratory results demonstrated that 21 (40.4%) patients had a creatinine level of more than 1.5 mg/dL, 35 (67.3%) patients had a creatine kinase (CK) of more than 200 U/L, 30 patients (57.7%) had a prothrombin time of more than 13 seconds, 29 (55.8%) patients had an aspartate aminotransferase (AST) of more than 45 U/L, and only 3 patients (5.7%) had a glucose of less than 60 mg/dL. Ethanol or illicit drugs were involved in 18 (34.6%) cases. The mean hospital stay was 4.7 days (range, 1-30 days), and there were 15 deaths (28.8%). A kappa score for interreviewer reliability was 0.69. Major limitations were the retrospective nature and lack of homogeneity in patient evaluation and test ordering. Hyperthermic patients with higher initial temperatures, hypotension, or low Glasgow Coma Scale

  7. Early experience in the combination of regional hyperthermia and radiotherapy

    International Nuclear Information System (INIS)

    Howard, G.C.W.; Bleehen, N.M.

    1987-01-01

    An annular array of radiative radiofrequency applicators (APA) has been developed by the BSD Corporation, Salt Lake City (USA) which has been shown to be capable of deep heating. The BSD 1000 clinical hyperthermia system has been installed at Cambridge for 18 months and a pilot study has been performed to assess the feasibility of pelvic regional hyperthermia in the treatment of extensive pelvic malignancy. The study confirms published data that the APA is capable of heating at depth within the pelvis. Therapeutic temperatures may be reached in the majority of treatments but are difficult to maintain due to acute toxicity. Steering of the area of maximal energy deposition may improve treatments considerably. A randomised trial is now being designed to assess whether the synergism between radiation and hyperthermia seen in superficial lesions can be demonstrated in tumours occurring in the pelvis. (orig./MG)

  8. Genetics Home Reference: malignant hyperthermia

    Science.gov (United States)

    ... 1722-30. Review. Citation on PubMed Litman RS, Rosenberg H. Malignant hyperthermia: update on susceptibility testing. JAMA. ... 27(10):977-89. Review. Citation on PubMed Rosenberg H, Davis M, James D, Pollock N, Stowell ...

  9. Hyperthermia and fatigue

    DEFF Research Database (Denmark)

    Nybo, Lars

    2008-01-01

    The present review addresses mechanisms of importance for hyperthermia-induced fatigue during short intense activities and prolonged exercise in the heat. Inferior performance during physical activities with intensities that elicit maximal oxygen uptake is to a large extent related to perturbation...... of the cardiovascular function, which eventually reduces arterial oxygen delivery to the exercising muscles. Accordingly, aerobic energy turnover is impaired and anaerobic metabolism provokes peripheral fatigue. In contrast, metabolic disturbances of muscle homeostasis are less important during prolonged exercise...... in the heat, because increased oxygen extraction compensates for the reduction in systemic blood flow. The decrease in endurance seems to involve changes in the function of the central nervous system (CNS) that lead to fatigue. The CNS fatigue appears to be influenced by neurotransmitter activity...

  10. Stability analysis of a deterministic dose calculation for MRI-guided radiotherapy

    Science.gov (United States)

    Zelyak, O.; Fallone, B. G.; St-Aubin, J.

    2018-01-01

    Modern effort in radiotherapy to address the challenges of tumor localization and motion has led to the development of MRI guided radiotherapy technologies. Accurate dose calculations must properly account for the effects of the MRI magnetic fields. Previous work has investigated the accuracy of a deterministic linear Boltzmann transport equation (LBTE) solver that includes magnetic field, but not the stability of the iterative solution method. In this work, we perform a stability analysis of this deterministic algorithm including an investigation of the convergence rate dependencies on the magnetic field, material density, energy, and anisotropy expansion. The iterative convergence rate of the continuous and discretized LBTE including magnetic fields is determined by analyzing the spectral radius using Fourier analysis for the stationary source iteration (SI) scheme. The spectral radius is calculated when the magnetic field is included (1) as a part of the iteration source, and (2) inside the streaming-collision operator. The non-stationary Krylov subspace solver GMRES is also investigated as a potential method to accelerate the iterative convergence, and an angular parallel computing methodology is investigated as a method to enhance the efficiency of the calculation. SI is found to be unstable when the magnetic field is part of the iteration source, but unconditionally stable when the magnetic field is included in the streaming-collision operator. The discretized LBTE with magnetic fields using a space-angle upwind stabilized discontinuous finite element method (DFEM) was also found to be unconditionally stable, but the spectral radius rapidly reaches unity for very low-density media and increasing magnetic field strengths indicating arbitrarily slow convergence rates. However, GMRES is shown to significantly accelerate the DFEM convergence rate showing only a weak dependence on the magnetic field. In addition, the use of an angular parallel computing strategy

  11. Corrigendum to "Stability analysis of a deterministic dose calculation for MRI-guided radiotherapy".

    Science.gov (United States)

    Zelyak, Oleksandr; Fallone, B Gino; St-Aubin, Joel

    2018-03-12

    Modern effort in radiotherapy to address the challenges of tumor localization and motion has led to the development of MRI guided radiotherapy technologies. Accurate dose calculations must properly account for the effects of the MRI magnetic fields. Previous work has investigated the accuracy of a deterministic linear Boltzmann transport equation (LBTE) solver that includes magnetic field, but not the stability of the iterative solution method. In this work, we perform a stability analysis of this deterministic algorithm including an investigation of the convergence rate dependencies on the magnetic field, material density, energy, and anisotropy expansion. The iterative convergence rate of the continuous and discretized LBTE including magnetic fields is determined by analyzing the spectral radius using Fourier analysis for the stationary source iteration (SI) scheme. The spectral radius is calculated when the magnetic field is included (1) as a part of the iteration source, and (2) inside the streaming-collision operator. The non-stationary Krylov subspace solver GMRES is also investigated as a potential method to accelerate the iterative convergence, and an angular parallel computing methodology is investigated as a method to enhance the efficiency of the calculation. SI is found to be unstable when the magnetic field is part of the iteration source, but unconditionally stable when the magnetic field is included in the streaming-collision operator. The discretized LBTE with magnetic fields using a space-angle upwind stabilized discontinuous finite element method (DFEM) was also found to be unconditionally stable, but the spectral radius rapidly reaches unity for very low density media and increasing magnetic field strengths indicating arbitrarily slow convergence rates. However, GMRES is shown to significantly accelerate the DFEM convergence rate showing only a weak dependence on the magnetic field. In addition, the use of an angular parallel computing strategy

  12. Stability analysis of a deterministic dose calculation for MRI-guided radiotherapy.

    Science.gov (United States)

    Zelyak, O; Fallone, B G; St-Aubin, J

    2017-12-14

    Modern effort in radiotherapy to address the challenges of tumor localization and motion has led to the development of MRI guided radiotherapy technologies. Accurate dose calculations must properly account for the effects of the MRI magnetic fields. Previous work has investigated the accuracy of a deterministic linear Boltzmann transport equation (LBTE) solver that includes magnetic field, but not the stability of the iterative solution method. In this work, we perform a stability analysis of this deterministic algorithm including an investigation of the convergence rate dependencies on the magnetic field, material density, energy, and anisotropy expansion. The iterative convergence rate of the continuous and discretized LBTE including magnetic fields is determined by analyzing the spectral radius using Fourier analysis for the stationary source iteration (SI) scheme. The spectral radius is calculated when the magnetic field is included (1) as a part of the iteration source, and (2) inside the streaming-collision operator. The non-stationary Krylov subspace solver GMRES is also investigated as a potential method to accelerate the iterative convergence, and an angular parallel computing methodology is investigated as a method to enhance the efficiency of the calculation. SI is found to be unstable when the magnetic field is part of the iteration source, but unconditionally stable when the magnetic field is included in the streaming-collision operator. The discretized LBTE with magnetic fields using a space-angle upwind stabilized discontinuous finite element method (DFEM) was also found to be unconditionally stable, but the spectral radius rapidly reaches unity for very low-density media and increasing magnetic field strengths indicating arbitrarily slow convergence rates. However, GMRES is shown to significantly accelerate the DFEM convergence rate showing only a weak dependence on the magnetic field. In addition, the use of an angular parallel computing strategy

  13. Magnetization curves of sintered heavy tungsten alloys for applications in MRI-guided radiotherapy

    International Nuclear Information System (INIS)

    Kolling, Stefan; Oborn, Bradley M.; Keall, Paul J.; Horvat, Joseph

    2014-01-01

    Purpose: Due to the current interest in MRI-guided radiotherapy, the magnetic properties of the materials commonly used in radiotherapy are becoming increasingly important. In this paper, measurement results for the magnetization (BH) curves of a range of sintered heavy tungsten alloys used in radiation shielding and collimation are presented. Methods: Sintered heavy tungsten alloys typically contain >90 % tungsten and 0 and the BH curve derived. Results: The iron content of the alloys was found to play a dominant role, directly influencing the magnetizationM and thus the nonlinearity of the BH curve. Generally, the saturation magnetization increased with increasing iron content of the alloy. Furthermore, no measurable magnetization was found for all alloys without iron content, despite containing up to 6% of nickel. For two samples from different manufacturers but with identical quoted nominal elemental composition (95% W, 3.5% Ni, 1.5% Fe), a relative difference in the magnetization of 11%–16% was measured. Conclusions: The measured curves show that the magnetic properties of sintered heavy tungsten alloys strongly depend on the iron content, whereas the addition of nickel in the absence of iron led to no measurable effect. Since a difference in the BH curves for two samples with identical quoted nominal composition from different manufacturers was observed, measuring of the BH curve for each individual batch of heavy tungsten alloys is advisable whenever accurate knowledge of the magnetic properties is crucial. The obtained BH curves can be used in FEM simulations to predict the magnetic impact of sintered heavy tungsten alloys

  14. Navigated MRI-guided liver biopsies in a closed-bore scanner: experience in 52 patients.

    Science.gov (United States)

    Moche, Michael; Heinig, Susann; Garnov, Nikita; Fuchs, Jochen; Petersen, Tim-Ole; Seider, Daniel; Brandmaier, Philipp; Kahn, Thomas; Busse, Harald

    2016-08-01

    To evaluate clinical effectiveness and diagnostic efficiency of a navigation device for MR-guided biopsies of focal liver lesions in a closed-bore scanner. In 52 patients, 55 biopsies were performed. An add-on MR navigation system with optical instrument tracking was used for image guidance and biopsy device insertion outside the bore. Fast control imaging allowed visualization of the true needle position at any time. The biopsy workflow and procedure duration were recorded. Histological analysis and clinical course/outcome were used to calculate sensitivity, specificity and diagnostic accuracy. Fifty-four of 55 liver biopsies were performed successfully with the system. No major and four minor complications occurred. Mean tumour size was 23 ± 14 mm and the skin-to-target length ranged from 22 to 177 mm. In 39 cases, access path was double oblique. Sensitivity, specificity and diagnostic accuracy were 88 %, 100 % and 92 %, respectively. The mean procedure time was 51 ± 12 min, whereas the puncture itself lasted 16 ± 6 min. On average, four control scans were taken. Using this navigation device, biopsies of poorly visible and difficult accessible liver lesions could be performed safely and reliably in a closed-bore MRI scanner. The system can be easily implemented in clinical routine workflow. • Targeted liver biopsies could be reliably performed in a closed-bore MRI. • The navigation system allows for image guidance outside of the scanner bore. • Assisted MRI-guided biopsies are helpful for focal lesions with a difficult access. • Successful integration of the method in clinical workflow was shown. • Subsequent system installation in an existing MRI environment is feasible.

  15. Extracting Visual Evoked Potentials from EEG Data Recorded During fMRI-guided Transcranial Magnetic Stimulation

    Science.gov (United States)

    Sadeh, Boaz; Yovel, Galit

    2014-01-01

    Transcranial Magnetic Stimulation (TMS) is an effective method for establishing a causal link between a cortical area and cognitive/neurophysiological effects. Specifically, by creating a transient interference with the normal activity of a target region and measuring changes in an electrophysiological signal, we can establish a causal link between the stimulated brain area or network and the electrophysiological signal that we record. If target brain areas are functionally defined with prior fMRI scan, TMS could be used to link the fMRI activations with evoked potentials recorded. However, conducting such experiments presents significant technical challenges given the high amplitude artifacts introduced into the EEG signal by the magnetic pulse, and the difficulty to successfully target areas that were functionally defined by fMRI. Here we describe a methodology for combining these three common tools: TMS, EEG, and fMRI. We explain how to guide the stimulator's coil to the desired target area using anatomical or functional MRI data, how to record EEG during concurrent TMS, how to design an ERP study suitable for EEG-TMS combination and how to extract reliable ERP from the recorded data. We will provide representative results from a previously published study, in which fMRI-guided TMS was used concurrently with EEG to show that the face-selective N1 and the body-selective N1 component of the ERP are associated with distinct neural networks in extrastriate cortex. This method allows us to combine the high spatial resolution of fMRI with the high temporal resolution of TMS and EEG and therefore obtain a comprehensive understanding of the neural basis of various cognitive processes. PMID:24893706

  16. Extracting visual evoked potentials from EEG data recorded during fMRI-guided transcranial magnetic stimulation.

    Science.gov (United States)

    Sadeh, Boaz; Yovel, Galit

    2014-05-12

    Transcranial Magnetic Stimulation (TMS) is an effective method for establishing a causal link between a cortical area and cognitive/neurophysiological effects. Specifically, by creating a transient interference with the normal activity of a target region and measuring changes in an electrophysiological signal, we can establish a causal link between the stimulated brain area or network and the electrophysiological signal that we record. If target brain areas are functionally defined with prior fMRI scan, TMS could be used to link the fMRI activations with evoked potentials recorded. However, conducting such experiments presents significant technical challenges given the high amplitude artifacts introduced into the EEG signal by the magnetic pulse, and the difficulty to successfully target areas that were functionally defined by fMRI. Here we describe a methodology for combining these three common tools: TMS, EEG, and fMRI. We explain how to guide the stimulator's coil to the desired target area using anatomical or functional MRI data, how to record EEG during concurrent TMS, how to design an ERP study suitable for EEG-TMS combination and how to extract reliable ERP from the recorded data. We will provide representative results from a previously published study, in which fMRI-guided TMS was used concurrently with EEG to show that the face-selective N1 and the body-selective N1 component of the ERP are associated with distinct neural networks in extrastriate cortex. This method allows us to combine the high spatial resolution of fMRI with the high temporal resolution of TMS and EEG and therefore obtain a comprehensive understanding of the neural basis of various cognitive processes.

  17. Theranostic Gd(III)-lipid microbubbles for MRI-guided focused ultrasound surgery.

    Science.gov (United States)

    Feshitan, Jameel A; Vlachos, Fotis; Sirsi, Shashank R; Konofagou, Elisa E; Borden, Mark A

    2012-01-01

    We have synthesized a biomaterial consisting of Gd(III) ions chelated to lipid-coated, size-selected microbubbles for utility in both magnetic resonance and ultrasound imaging. The macrocyclic ligand DOTA-NHS was bound to PE headgroups on the lipid shell of pre-synthesized microbubbles. Gd(III) was then chelated to DOTA on the microbubble shell. The reaction temperature was optimized to increase the rate of Gd(III) chelation while maintaining microbubble stability. ICP-OES analysis of the microbubbles determined a surface density of 7.5 × 10(5) ± 3.0 × 10(5) Gd(III)/μm(2) after chelation at 50 °C. The Gd(III)-bound microbubbles were found to be echogenic in vivo during high-frequency ultrasound imaging of the mouse kidney. The Gd(III)-bound microbubbles also were characterized by magnetic resonance imaging (MRI) at 9.4 T by a spin-echo technique and, surprisingly, both the longitudinal and transverse proton relaxation rates were found to be roughly equal to that of no-Gd(III) control microbubbles and saline. However, the relaxation rates increased significantly, and in a dose-dependent manner, after sonication was used to fragment the Gd(III)-bound microbubbles into non-gas-containing lipid bilayer remnants. The longitudinal (r(1)) and transverse (r(2)) molar relaxivities were 4.0 ± 0.4 and 120 ± 18 mM(-1)s(-1), respectively, based on Gd(III) content. The Gd(III)-bound microbubbles may find application in the measurement of cavitation events during MRI-guided focused ultrasound therapy and to track the biodistribution of shell remnants. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Combined effects of hyperthermia and radiation in cultured mammalian cells

    International Nuclear Information System (INIS)

    Ben-Hur, E.; Elkind, M.M.; Riklis, E.

    1977-01-01

    Hyperthermia (temperatures of 39 0 C or higher) enhances the killing of mammalian cells by ionizing radiation (fission-spectrum neutrons and x-rays). The nature and the magnitude of the enhanced radiation killing varies with temperature and for a fixed temperature during irradiation, the enhanced lethality varies inversely with dose rate. For temperatures up to 41 0 C, dose fractionation measurements indicate that hyperthermia inhibits the repair of sublethal damage. At higher temperatures, the expression of potentially lethal damage is enhanced. Since the effect of heat is greatest in cells irradiated during DNA synthesis, the radiation age-response pattern is flattened by hyperthermia. In addition to the enhanced cell killing described above, three other features of the effect of hyperthermia are important in connection with the radiation treatment of cancer. The first is that heat selectively sensitizes S-phase cells to radiation. The second is that it takes radiation survivors 10 to 20 hrs after a modest heat treatment to recover their ability to repair sublethal damage. And the third is that hyperthermia reduces the magnitude of the oxygen enhancement ratio. Thus, heat if applied selectively, could significantly increase the margin of damage between tumors and normal tissues

  19. Covalent DNA-protein crosslinking occurs after hyperthermia and radiation

    International Nuclear Information System (INIS)

    Cress, A.E.; Bowden, G.T.

    1983-01-01

    Covalent DNA-protein crosslinks occur in exponentially growing mouse leukemia cells (L1210) after exposure to ionizing radiation. The amount of DNA-protein crosslinks as measured by a filter binding assay is dose dependent upon X irradiation. Although hyperthermia and radiation in combination are synergistic with respect to cell lethality, the combination does not result in an increase of DNA-protein crosslinks when assayed immediately following treatments. Hyperthermia (43 degrees C/15 min) given prior to radiation does not alter the radiation dose dependency of the amount of initial crosslinking. In addition, the amount of DNA-protein crosslinking produced by heat plus radiation is independent of the length of heating the cells at 43 degrees C. The DNA-protein crosslinks produced by 50-Gy X ray alone are removed after 2 hr at 37 degrees C. However, if hyperthermia (43 degrees C/15 min) is given prior to 100-Gy X ray, the removal of DNA-protein crosslinks is delayed until 4.0 hr after radiation. Phospho-serine and phospho-threonine bonds are not produced with either radiation or the combination of hyperthermia plus radiation as judged by the resistance of the bonds to guanidine hydrochloride. However, hyperthermia plus radiation causes an increase in phosphate to nitrogen type bonding. These results show that radiation alone causes covalent DNA-protein crosslinks. Hyperthermia in combination with radiation does not increase the total amount of the crosslinks but delays the removal of the crosslinks and alters the distribution of the types of chemical bonding. These data suggest that the synergistic action on hyperthermia with radiation is more related to the rate of removal and the type of chemical bonding involved in the covalent DNA-protein crosslinks rather than the amount of DNA-protein crosslinks

  20. The Dartmouth Center for Cancer Nanotechnology Excellence: magnetic hyperthermia.

    Science.gov (United States)

    Baker, Ian; Fiering, Steve N; Griswold, Karl E; Hoopes, P Jack; Kekalo, Katerina; Ndong, Christian; Paulsen, Keith; Petryk, Alicea A; Pogue, Brian; Shubitidze, Fridon; Weaver, John

    2015-01-01

    The Dartmouth Center for Cancer Nanotechnology Excellence - one of nine funded by the National Cancer Institute as part of the Alliance for Nanotechnology in Cancer - focuses on the use of magnetic nanoparticles for cancer diagnostics and hyperthermia therapy. It brings together a diverse team of engineers and biomedical researchers with expertise in nanomaterials, molecular targeting, advanced biomedical imaging and translational in vivo studies. The goal of successfully treating cancer is being approached by developing nanoparticles, conjugating them with Fabs, hyperthermia treatment, immunotherapy and sensing treatment response.

  1. Recognizing and managing a malignant hyperthermia crisis: guidelines from the European Malignant Hyperthermia Group

    DEFF Research Database (Denmark)

    Glahn, K P E; Ellis, F R; Halsall, P J

    2010-01-01

    Survival from a malignant hyperthermia (MH) crisis is highly dependent on early recognition and prompt action. MH crises are very rare and an increasing use of total i.v. anaesthesia is likely to make it even rarer, leading to the potential risk of reduced awareness of MH. In addition, dantrolene....... The guidelines consist of two textboxes: Box 1 on recognizing MH and Box 2 on the treatment of an MH crisis....

  2. Distortion-free diffusion MRI using an MRI-guided Tri-Cobalt 60 radiotherapy system: Sequence verification and preliminary clinical experience.

    Science.gov (United States)

    Gao, Yu; Han, Fei; Zhou, Ziwu; Cao, Minsong; Kaprealian, Tania; Kamrava, Mitchell; Wang, Chenyang; Neylon, John; Low, Daniel A; Yang, Yingli; Hu, Peng

    2017-10-01

    Monitoring tumor response during the course of treatment and adaptively modifying treatment plan based on tumor biological feedback may represent a new paradigm for radiotherapy. Diffusion MRI has shown great promises in assessing and predicting tumor response to radiotherapy. However, the conventional diffusion-weighted single-shot echo-planar-imaging (DW-ssEPI) technique suffers from limited resolution, severe distortion, and possibly inaccurate ADC at low field strength. The purpose of this work was to develop a reliable, accurate and distortion-free diffusion MRI technique that is practicable for longitudinal tumor response evaluation and adaptive radiotherapy on a 0.35 T MRI-guided radiotherapy system. A diffusion-prepared turbo spin echo readout (DP-TSE) sequence was developed and compared with the conventional diffusion-weighted single-shot echo-planar-imaging sequence on a 0.35 T MRI-guided radiotherapy system (ViewRay). A spatial integrity phantom was used to quantitate and compare the geometric accuracy of the two diffusion sequences for three orthogonal orientations. The apparent diffusion coefficient (ADC) accuracy was evaluated on a diffusion phantom under both 0 °C and room temperature to cover a diffusivity range between 0.40 × 10 -3 and 2.10 × 10 -3 mm 2 /s. Ten room temperature measurements repeated on five different days were conducted to assess the ADC reproducibility of DP-TSE. Two glioblastoma (GBM) and six sarcoma patients were included to examine the in vivo feasibility. The target registration error (TRE) was calculated to quantitate the geometric accuracy where structural CT or MR images were co-registered to the diffusion images as references. ADC maps from DP-TSE and DW-ssEPI were calculated and compared. A tube phantom was placed next to patients not treated on ViewRay, and ADCs of this reference tube were also compared. The proposed DP-TSE passed the spatial integrity test (< 1 mm within 100 mm radius and < 2 mm within 175 mm radius

  3. Comparative evaluation of combined irradiation and hyperthermia versus irradiation alone

    International Nuclear Information System (INIS)

    Sawas-Dimopoulou, C.; Iordanou, I.; Uzunoglu, N.; Dardoufas, K.; Kouloulias, V.; Maris, T.; Kotaridis, S.

    1994-01-01

    Controvesy remains as to the treatment schedule producing better results in combined hyperthermia and X-ray therapy. Our experience concerning combined therapy of the solid tumour Walker carcinoma is reported. Male Wistar rats were submitted to treatment on the ninth day after transplantation of the tumour. Two groups of rats received either a therapeutic X-ray dose of 800 cGy by a 6-MeV linear accelerator (Mevatron, Siemens) or treatment by 432 MHz of microwaves with continuous control of tumour tissue temperature to 44±1 C for 45 min. Another group of rats was submitted to a combined treatment, with X-ray therapy preceding hyperthermia by 24 h. The last group of animals constituted the control rats. Greater tumour regression and longer survival times were obtained with the combined treatment. The gain factor for survival time was equal to 1.85 after combined treatment compared with 1.30 after X-ray therapy and 1.05 after hyperthermia. In conclusion, the results suggest that in the above schedule of combined treatment, hyperthermia applied to a solid tumour 24 h after a single dose of X-rays enhances the beneficial effect of therapy. (orig.)

  4. Hybrid Approach for Biliary Interventions Employing MRI-Guided Bile Duct Puncture with Near-Real-Time Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Wybranski, Christian, E-mail: Christian.Wybranski@uk-koeln.de [University Hospital of Cologne, Department of Diagnostic and Interventional Radiology (Germany); Pech, Maciej [Otto-von-Guericke University Medical School, Department of Radiology and Nuclear Medicine (Germany); Lux, Anke [Otto-von-Guericke University Medical School, Institute of Biometry and Medical Informatics (Germany); Ricke, Jens; Fischbach, Frank; Fischbach, Katharina [Otto-von-Guericke University Medical School, Department of Radiology and Nuclear Medicine (Germany)

    2017-06-15

    ObjectiveTo assess the feasibility of a hybrid approach employing MRI-guided bile duct (BD) puncture for subsequent fluoroscopy-guided biliary interventions in patients with non-dilated (≤3 mm) or dilated BD (≥3 mm) but unfavorable conditions for ultrasonography (US)-guided BD puncture.MethodsA total of 23 hybrid interventions were performed in 21 patients. Visualization of BD and puncture needles (PN) in the interventional MR images was rated on a 5-point Likert scale by two radiologists. Technical success, planning time, BD puncture time and positioning adjustments of the PN as well as technical success of the biliary intervention and complication rate were recorded.ResultsVisualization even of third-order non-dilated BD and PN was rated excellent by both radiologists with good to excellent interrater agreement. MRI-guided BD puncture was successful in all cases. Planning and BD puncture times were 1:36 ± 2.13 (0:16–11:07) min. and 3:58 ± 2:35 (1:11–9:32) min. Positioning adjustments of the PN was necessary in two patients. Repeated capsular puncture was not necessary in any case. All biliary interventions were completed successfully without major complications.ConclusionA hybrid approach which employs MRI-guided BD puncture for subsequent fluoroscopy-guided biliary intervention is feasible in clinical routine and yields high technical success in patients with non-dilated BD and/or unfavorable conditions for US-guided puncture. Excellent visualization of BD and PN in near-real-time interventional MRI allows successful cannulation of the BD.

  5. MRI-guided percutaneous cryoablation of renal tumors: Use of external manual displacement of adjacent bowel loops

    International Nuclear Information System (INIS)

    Tuncali, Kemal; Morrison, Paul R.; Tatli, Servet; Silverman, Stuart G.

    2006-01-01

    Purpose: We sought to investigate retrospectively the safety and effectiveness of using external hand compression to displace adjacent bowel loops during MRI-guided percutaneous cryoablation of renal tumors. Materials and methods: Fourteen patients (six women, eight men; mean age: 72 years) with 15 renal tumors (mean diameter: 2.4 cm; range: 1.4-4.6 cm) adjacent to bowel were treated with MRI-guided percutaneous cryoablation during which bowel was displaced manually. Bowel loop of concern was ascending colon (n 5), descending colon (n = 8), descending colon and small bowel (n = 1), ascending colon and small bowel (n = 1). To analyze effectiveness of the maneuver, mean distance between tumor margin and bowel before and after the maneuver were compared and analyzed using paired Student's t-test. Minimum distance between iceball edge and adjacent bowel with external manual displacement during freezing was also measured. Safety was assessed by analyzing post-procedural MR imaging for adjacent bowel wall thickening and focal fluid collections as well as patients' clinical and imaging follow-up. Results: Mean distance between tumor margin and closest adjacent bowel increased from 0.8 cm (range: 0-2 cm) before external manual compression to 2.6 cm (range: 1.6-4.1 cm) with manual displacement (p < 0.01). Mean minimum distance between iceball edge and closest adjacent bowel during the procedures was 1.6 cm (range: 0.5-3.5 cm). No evidence of bowel injury was encountered. Twelve of 15 tumors had follow-up (mean: 10 months) that showed no tumor recurrence. Conclusion: MRI-guided percutaneous cryoablation of renal tumors adjacent to bowel can be done safely and effectively using external hand compression to displace bowel loops

  6. Improved survival in rats with glioma using MRI-guided focused ultrasound and microbubbles to disrupt the blood-brain barrier and deliver Doxil

    Science.gov (United States)

    Aryal, Muna; Zhi Zhang, Yong; Vykhodtseva, Natalia; Park, Juyoung; Power, Chanikarn; McDannold, Nathan

    2012-02-01

    Blood-brain-barrier (BBB) limits the transportation of most neuropeptides, proteins (enzymes, antibodies), chemotherapeutic agents, and genes that have therapeutic potential for the treatment of brain diseases. Different methods have been used to overcome this limitation, but they are invasive, non-targeted, or require the development of new drugs. We have developed a method that uses MRI-guided focused ultrasound (FUS) combined with circulating microbubbles to temporarily open BBB in and around brain tumors to deliver chemotherapy agents. Here, we tested whether this noninvasive technique could enhance the effectiveness of a chemotherapy agent (Doxil). Using 690 kHz FUS transducer and microbubble (Definity), we induced BBB disruption in intracranially-implanted 9L glioma tumors in rat's brain in three weekly sessions. Animals who received BBB disruption and Doxil had a median survival time of 34.5 days, which was significantly longer than that found in control animals which is 16, 18.5, 21 days who received no treatment, BBB disruption only and Doxil only respectively This work demonstrates that FUS technique has promise in overcoming barriers to drug delivery, which are particularly stark in the brain due to the BBB.

  7. Magnetic Hyperthermia and Radiation Therapy: Radiobiological Principles and Current Practice †

    Directory of Open Access Journals (Sweden)

    Spiridon V. Spirou

    2018-06-01

    Full Text Available Hyperthermia, though by itself generally non-curative for cancer, can significantly increase the efficacy of radiation therapy, as demonstrated by in vitro, in vivo, and clinical results. Its limited use in the clinic is mainly due to various practical implementation difficulties, the most important being how to adequately heat the tumor, especially deep-seated ones. In this work, we first review the effects of hyperthermia on tissue, the limitations of radiation therapy and the radiobiological rationale for combining the two treatment modalities. Subsequently, we review the theory and evidence for magnetic hyperthermia that is based on magnetic nanoparticles, its advantages compared with other methods of hyperthermia, and how it can be used to overcome the problems associated with traditional techniques of hyperthermia.

  8. MRI-guided Wire Localization Surgical Biopsy in an Adolescent Patient with a Difficult to Diagnose Case of Lymphoma

    International Nuclear Information System (INIS)

    Thompson, Scott M.; Gorny, Krzysztof R.; Jondal, Danielle E.; Rech, Karen L.; Mardini, Samir; Woodrum, David A.

    2017-01-01

    A 17-year-old previously healthy female presented with a progressive soft tissue infiltrative process involving the neck and thorax. Extensive diagnostic evaluation including multiple imaging, laboratory, and biopsy studies was nondiagnostic. Due to an urgent need to establish a diagnosis and several previous nondiagnostic biopsies, she was referred to interventional radiology for MRI-guided wire localization immediately prior to open surgical biopsy. Under general anesthesia, wires were placed in the areas of increased T2 signal within the bilateral splenius capitis muscles using intermittent MRI-guidance followed by immediate surgical biopsy down to the wires. Pathology confirmed the diagnosis of diffuse large B-cell lymphoma.

  9. MRI-guided Wire Localization Surgical Biopsy in an Adolescent Patient with a Difficult to Diagnose Case of Lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Scott M., E-mail: Thompson.scott@mayo.edu; Gorny, Krzysztof R.; Jondal, Danielle E. [Mayo Clinic College of Medicine, Department of Radiology (United States); Rech, Karen L. [Mayo Clinic College of Medicine, Department of Laboratory Medicine and Pathology (United States); Mardini, Samir [Mayo Clinic College of Medicine, Division of Plastic and Reconstructive Surgery, Department of Surgery (United States); Woodrum, David A. [Mayo Clinic College of Medicine, Division of Vascular and Interventional Radiology, Department of Radiology (United States)

    2017-01-15

    A 17-year-old previously healthy female presented with a progressive soft tissue infiltrative process involving the neck and thorax. Extensive diagnostic evaluation including multiple imaging, laboratory, and biopsy studies was nondiagnostic. Due to an urgent need to establish a diagnosis and several previous nondiagnostic biopsies, she was referred to interventional radiology for MRI-guided wire localization immediately prior to open surgical biopsy. Under general anesthesia, wires were placed in the areas of increased T2 signal within the bilateral splenius capitis muscles using intermittent MRI-guidance followed by immediate surgical biopsy down to the wires. Pathology confirmed the diagnosis of diffuse large B-cell lymphoma.

  10. Targeting therapy-resistant cancer stem cells by hyperthermia

    DEFF Research Database (Denmark)

    Oei, A L; Vriend, L E M; Krawczyk, P M

    2017-01-01

    Eradication of all malignant cells is the ultimate but challenging goal of anti-cancer treatment; most traditional clinically-available approaches fail because there are cells in a tumour that either escape therapy or become therapy-resistant. A subpopulation of cancer cells, the cancer stem cells...... are limited. Here, we argue that hyperthermia - a therapeutic approach based on local heating of a tumour - is potentially beneficial for targeting CSCs in solid tumours. First, hyperthermia has been described to target cells in hypoxic and nutrient-deprived tumour areas where CSCs reside and ionising...

  11. Hyperthermia, immunity and metastases

    International Nuclear Information System (INIS)

    Lopatin, V.F.

    1983-01-01

    The analysis of literature data concerning local hyperthermia effects shows that temperatures over 41-42 deg C (in the whole tumor volume), causing tumor growth inhibition and cell injury, can change antigenic nature of a malignant tissue. The tumor injured by thermal effect is able probably the full length of time of injured tissue resorption to maintain at a sufficiently high level antitumoral immunity and lay obstacles to emergence of metastases or even cause regression of those tumoral foci which have not been exposed to direct effect of the injuring agent. The facts of tumoral foci regression take place also upon radiation effect which is associated as well with participation of immune mechanisms. In.experiments with animals an essential increase of immunogenic character of malignant cells exposed to ionizing radiation effect has been observed. It follows that radiation injury of tumoral tissue as well as thermal one is able to stimulate antitumoral immunity and reduce the probability of emergence of metastases. But in case of radiotherapy immunosuppression effect of ionizing radiation (at the expense of inhibition of proliferation and death of immunocompetent cells) can essentially overlap immunostimulating effect related to the changes in antigenic character of tumoral cells

  12. Enhancement of immunological activity after mild hyperthermia

    International Nuclear Information System (INIS)

    Noguchi, Kenichi; Hasegawa, Takeo; Takahashi, Tohru

    2002-01-01

    At present, hyperthermia is clinically very important as interdisciplinary therapeutic method, and studies are being performed on combined effects with surgical treatment, radiotherapy, chemotherapy and gene therapy for the treatment of malignant tumors. We evaluated the effects of hyperthermia under temperature of 42.5C and demonstrated that the activation of immunological response is increased and anti-tumor effect cabn be obtained in this studies. We used animals were C3H mice (male,7W) bearing SCC-VII tumor on femur skin. Then, the mice were divided to 10 mice in each group, and only femur region was immersed in warm water for thermal treatment. Also we measured the tumor growth, changes of blood cell fraction and NK cell activity. The results of the present study confirmed: (1) Anti-tumor effect can be given by thermal treatment at relatively mild temperature (mild temperature at 39C-42C); (2) The increase of neutrophils is dependent on the quantity of heat added; (3) Immunological response of monocytes and lymphocytes is associated with it; (4) Activity of the immunological potency as a whole such as activation of NK cells was also confirmed

  13. Numerical modeling for an electric-field hyperthermia applicator

    Science.gov (United States)

    Wu, Te-Kao; Chou, C. K.; Chan, K. W.; Mcdougall, J.

    1993-01-01

    Hyperthermia, in conjunction with radiation and chemotherapy for treatment of cancers, is an area of current concern. Experiments have shown that hyperthermia can increase the potency of many chemotherapy drugs and the effectiveness of radiation for treating cancer. A combination of whole body or regional hyperthermia with chemotherapy or radiation should improve treatment results. Conventional methods for inducing whole body hyperthermia, such as exposing a patient in a radiant cabinet or under a hot water blanket, conduct heat very slowly from the skin to the body core. Thus a more efficient system, such as the three-plate electric-field hyperthermia applicator (EHA), is developed. This three-plate EHA has one top plate over and two lower plates beneath the patient. It is driven at 27.12 MHz with 500 Watts through a matching circuit. Using this applicator, a 50 kg pig was successfully heated to 42 C within 45 minutes. However, phantom and animal studies have indicated non-uniform heating near the side of the body. In addition, changes in the size and distance between the electrode plates can affect the heating (or electromagnetic field) pattern. Therefore, numerical models using the method of moments (MOM) or the finite difference time domain (FDTD) technique are developed to optimize the heating pattern of this EHA before it is used for human trials. The accuracy of the numerical modeling has been achieved by the good agreement between the MOM and FDTD results for the three-plate EHA without a biological body. The versatile FDTD technique is then applied to optimize the EHA design with a human body. Both the numerical and measured data in phantom blocks will be presented. The results of this study will be used to design an optimized system for whole body or regional hyperthermia.

  14. Improving efficacy of hyperthermia in oncology by exploiting biological mechanisms

    DEFF Research Database (Denmark)

    van den Tempel, Nathalie; Horsman, Michael R; Kanaar, Roland

    2016-01-01

    It has long been established that hyperthermia increases the therapeutic benefit of radiation and chemotherapy in cancer treatment. During the last few years there have been substantial technical improvements in the sources used to apply and measure heat, which greatly increases enthusiasm for th...

  15. Synthesis, characterization and hemolysis studies of Zn{sub (1−x)}Ca{sub x}Fe{sub 2}O{sub 4} ferrites synthesized by sol-gel for hyperthermia treatment applications

    Energy Technology Data Exchange (ETDEWEB)

    Jasso-Terán, Rosario Argentina, E-mail: arg.jasso@gmail.com; Cortés-Hernández, Dora Alicia; Sánchez-Fuentes, Héctor Javier; Reyes-Rodríguez, Pamela Yajaira; León-Prado, Laura Elena de; Escobedo-Bocardo, José Concepción; Almanza-Robles, José Manuel

    2017-04-01

    The synthesis of Zn{sub (1−x)}Ca{sub x}Fe{sub 2}O{sub 4} nanoparticles, x=0, 0.25, 0.50, 0.75 and 1.0, was performed by sol-gel method followed by a heat treatment at 400 °C for 30 min. These ferrites showed nanometric sizes and nearly superparamagnetic behavior. The Zn{sub 0.50}Ca{sub 0.50}Fe{sub 2}O{sub 4} and CaFe{sub 2}O{sub 4} ferrites presented a size within the range of 12–14 nm and appropriate heating ability for hyperthermia applications. Hemolysis testing demonstrated that Zn{sub 0.50}Ca{sub 0.50}Fe{sub 2}O{sub 4} ferrite was not cytotoxic when using 10 mg of ferrite/mL of solution. According to the results obtained, Zn{sub 0.50}Ca{sub 0.50}Fe{sub 2}O{sub 4} is a potential material for cancer treatment by magnetic hyperthermia therapy. - Highlights: • The synthesis of Zn{sub (1−x)}Ca{sub x}Fe{sub 2}O{sub 4} ferrites was performed by sol-gel method. • CaFe{sub 2}O{sub 4} and Zn{sub 0.50}Ca{sub 0.}50Fe{sub 2}O{sub 4} ferrites showed heating ability. • The Zn{sub 0.50}Ca{sub 0.50}Fe{sub 2}O{sub 4} ferrite demonstrated to be no hemolytic.

  16. Signal-inducing bone cements for MRI-guided spinal cementoplasty: evaluation of contrast-agent-based polymethylmethacrylate cements

    International Nuclear Information System (INIS)

    Bail, Hermann Josef; Tsitsilonis, Serafim; Wichlas, Florian; Sattig, Christoph; Papanikolaou, Ioannis; Teichgraeber, Ulf Karl Mart

    2012-01-01

    The purpose of this work is to evaluate two signal-inducing bone cements for MRI-guided spinal cementoplasty. The bone cements were made of polymethylmethacrylate (PMMA, 5 ml monomeric, 12 g polymeric) and gadoterate meglumine as a contrast agent (CA, 0-40 μl) with either saline solution (NaCl, 2-4 ml) or hydroxyapatite bone substitute (HA, 2-4 ml). The cement's signal was assessed in an open 1-Tesla MR scanner, with T1W TSE and fast interventional T1W TSE pulse sequences, and the ideal amount of each component was determined. The compressive and bending strength for different amounts of NaCl and HA were evaluated. The cement's MRI signal depended on the concentration of CA, the amount of NaCl or HA, and the pulse sequence. The signal peaks were recorded between 1 and 10 μl CA per ml NaCl or HA, and were higher in fast T1W TSE than in T1W TSE images. The NaCl-PMMA-CA cements had a greater MRI signal intensity and compressive strength; the HA-PMMA-CA cements had a superior bending strength. Concerning the MR signal and biomechanical properties, these cements would permit MRI-guided cementoplasty. Due to its higher signal and greater compressive strength, the NaCl-PMMA-CA compound appears to be superior to the HA-PMMA-CA compound. (orig.)

  17. Clinically Relevant Pharmacological Strategies That Reverse MDMA-Induced Brain Hyperthermia Potentiated by Social Interaction.

    Science.gov (United States)

    Kiyatkin, Eugene A; Ren, Suelynn; Wakabayashi, Ken T; Baumann, Michael H; Shaham, Yavin

    2016-01-01

    MDMA-induced hyperthermia is highly variable, unpredictable, and greatly potentiated by the social and environmental conditions of recreational drug use. Current strategies to treat pathological MDMA-induced hyperthermia in humans are palliative and marginally effective, and there are no specific pharmacological treatments to counteract this potentially life-threatening condition. Here, we tested the efficacy of mixed adrenoceptor blockers carvedilol and labetalol, and the atypical antipsychotic clozapine, in reversing MDMA-induced brain and body hyperthermia. We injected rats with a moderate non-toxic dose of MDMA (9 mg/kg) during social interaction, and we administered potential treatment drugs after the development of robust hyperthermia (>2.5 °C), thus mimicking the clinical situation of acute MDMA intoxication. Brain temperature was our primary focus, but we also simultaneously recorded temperatures from the deep temporal muscle and skin, allowing us to determine the basic physiological mechanisms of the treatment drug action. Carvedilol was modestly effective in attenuating MDMA-induced hyperthermia by moderately inhibiting skin vasoconstriction, and labetalol was ineffective. In contrast, clozapine induced a marked and immediate reversal of MDMA-induced hyperthermia via inhibition of brain metabolic activation and blockade of skin vasoconstriction. Our findings suggest that clozapine, and related centrally acting drugs, might be highly effective for reversing MDMA-induced brain and body hyperthermia in emergency clinical situations, with possible life-saving results.

  18. Modification of radiation damage in CHO cells by hyperthermia at 40 and 450C

    International Nuclear Information System (INIS)

    Henle, K.J.; Leeper, D.B.

    1977-01-01

    Low hyperthermia at 40 0 C either before or after X irradiation did not alter the slope of the radiation dose-cell survival curve but reduced the D/sub q/ from 145 to 41 or to 0 rad for a pre- or postirradiation incubation period of 2 hr at 40 0 C, respectively. In contrast, hyperthermia at 45 0 C increased the slope of the radiation survival curve by a factor of 1.7 for a radiation pretreatment of 10 min at 45 0 C, but only by 1.3 for the same treatment immediately after irradiation. The corresponding D/sub q/'s were 262 and 138 rad, respectively. A combination of 45 and 40 0 C hyperthermia (10 min at 45 0 C + 2 hr at 40 0 C + X) resulted in a superposition of the individual effects of 45 or 40 0 C hyperthermia on the radiation survival curve. In addition, the radiation survival curve was shifted downward by a factor of three due to the potentiation of 45 0 C hyperthermia damage by postincubation at 40 0 C. Repair of sublethal radiation damage was completely suppressed during incubation at 40 following hyperthermia at 45 0 C. However, when cells were returned to 37 0 C, even after 6 hr at 40 following 45 0 C hyperthermia, the capacity to accumulate and repair sublethal radiation damage was immediately restored. These findings imply that the hyperthermia damage from low or high temperatures interacts differentially with radiation damage. Low hyperthermia at 40 0 C may affect principally the radiation repair system, whereas 45 0 C hyperthermia probably alters the radiation target more severely than the repair system

  19. Covalent DNA-protein crosslinking occurs after hyperthermia and radiation

    International Nuclear Information System (INIS)

    Cress, A.E.; Bowden, G.T.

    1983-01-01

    Covalent DNA-protein crosslinks occur in exponentially growing mouse leukemia cells (L1210) after exposure to ionizing radiation. The amount of DNA-protein crosslinks as measured by a filter binding assay is dose dependent upon x irradiation. Although hyperthermia and radiation in combination are synergistic with respect to cell lethality, the combination does not result in an increase of DNA-protein crosslinks when assayed immediately following treatments. Hyperthermia (43 0 C/15 min) given prior to radiation dose not alter the radiation dose dependency of the amount of initial crosslinking. In addition, the amount of DNA-protein crosslinking produced by heat plus radiation is independent of the length of heating the cells at 43 0 C. The DNA-protein crosslinks produced y 50-Gy x ray alone are removed after 2 hr at 37 0 C. However, if hyperthermia (43 0 C/15 min) is given prior to 100-Gy x ray, the removal of DNA-protein crosslinks is delayed until 4.0 hr after radiation. Phospho-serine and phospho-threonine bonds are not produced with either radiation or the combination of hyperthermia plus radiation as judged by the resistance of the bonds to guanidine hydrochloride. However, hyperthermia plus radiation causes an increase in phosphate to nitrogen type bonding. These results show that radiation alone causes covalent DNA-protein crosslinks. Hyperthermia in combination with radiation does not increase the total amount of the crosslinks but delays the removal of the crosslinks and alters the distribution of the types of chemical bonding

  20. On the temperature control in self-controlling hyperthermia therapy

    Energy Technology Data Exchange (ETDEWEB)

    Ebrahimi, Mahyar, E-mail: ebrahimi_m@mehr.sharif.ir

    2016-10-15

    In self-controlling hyperthermia therapy, once the desired temperature is reached, the heat generation ceases and overheating is prevented. In order to design a system that generates sufficient heat without thermal ablation of surrounding healthy tissue, a good understanding of temperature distribution and its change with time is imperative. This study is conducted to extend our understanding about the heat generation and transfer, temperature distribution and temperature rise pattern in the tumor and surrounding tissue during self-controlling magnetic hyperthermia. A model consisting of two concentric spheres that represents the tumor and its surrounding tissue is considered and temperature change pattern and temperature distribution in tumor and surrounding tissue are studied. After describing the model and its governing equations and constants precisely, a typical numerical solution of the model is presented. Then it is showed that how different parameters like Curie temperature of nanoparticles, magnetic field amplitude and nanoparticles concentration can affect the temperature change pattern during self-controlling magnetic hyperthermia. The model system herein discussed can be useful to gain insight on the self-controlling magnetic hyperthermia while applied to cancer treatment in real scenario and can be useful for treatment strategy determination. - Highlights: • Temperature change pattern in tumor and surrounding tissue are studied. • The model system herein can be useful for treatment strategy determination. • In the work described herein, emphasis is on the effect of low Curie temperature. • If the equilibrium temperature can be tuned appropriately, the stay time will be infinite.

  1. On the temperature control in self-controlling hyperthermia therapy

    International Nuclear Information System (INIS)

    Ebrahimi, Mahyar

    2016-01-01

    In self-controlling hyperthermia therapy, once the desired temperature is reached, the heat generation ceases and overheating is prevented. In order to design a system that generates sufficient heat without thermal ablation of surrounding healthy tissue, a good understanding of temperature distribution and its change with time is imperative. This study is conducted to extend our understanding about the heat generation and transfer, temperature distribution and temperature rise pattern in the tumor and surrounding tissue during self-controlling magnetic hyperthermia. A model consisting of two concentric spheres that represents the tumor and its surrounding tissue is considered and temperature change pattern and temperature distribution in tumor and surrounding tissue are studied. After describing the model and its governing equations and constants precisely, a typical numerical solution of the model is presented. Then it is showed that how different parameters like Curie temperature of nanoparticles, magnetic field amplitude and nanoparticles concentration can affect the temperature change pattern during self-controlling magnetic hyperthermia. The model system herein discussed can be useful to gain insight on the self-controlling magnetic hyperthermia while applied to cancer treatment in real scenario and can be useful for treatment strategy determination. - Highlights: • Temperature change pattern in tumor and surrounding tissue are studied. • The model system herein can be useful for treatment strategy determination. • In the work described herein, emphasis is on the effect of low Curie temperature. • If the equilibrium temperature can be tuned appropriately, the stay time will be infinite.

  2. SU-F-J-125: Effects of Couch Position Variability On Dosimetric Accuracy with An MRI-Guided Co-60 Radiation Therapy Machine

    Energy Technology Data Exchange (ETDEWEB)

    Chow, P; Thomas, D; Agazaryan, N; Cao, M; Low, D; Yang, Y; Lamb, J [UCLA, Los Angeles, CA (United States)

    2016-06-15

    Purpose: Magnetic resonance imaging (MRI) guidance in radiation therapy brings real-time imaging and adaptive planning into the treatment vault where it can account for interfraction and intrafraction movement of soft tissue. The only commercially-available MRI-guided radiation therapy device is a three-head 60Co and MRI system with an integrated treatment planning system (TPS). An up to 20% attenuation of the beam by the couch is well modeled in the TPS. However, variations in the patient’s day-to-day position introduce discrepancies in the actual couch position relative its location as modeled in the treatment plan. For this reason, our institution avoids plans with beams that pass through or near the couch edges. This study looks at plans without restriction on beam angles and investigates the effects of couch shift by simulating shifts of the couch relative to the patient, in order to determine whether couch edge avoidance restrictions can be lifted. Methods: A total of 27 plans from 23 patients were investigated. Couch shifts of 1 and 2 cm were introduced in combinations of lateral and vertical direction to simulate variations in patient positioning on the couch giving 16 shifted plans per reference plan. The shift values of 1 and 2 cm were based on shifts recorded in 320 treatment fractions. Results: Measured couch attenuation versus TPS modeled agreed within 2.1%. Planning Target Volume (PTV) D95 changed less than 1% for 1 and 2 cm couch shifts in only the x-direction and less than 3% for all directions. Conclusion: The dosimetry of all plans with shifts up to ±2 cm was within reasonable clinical tolerances. Robustness of a plan to couch shifts can be tested in the TPS. Inclusion of beams traversing the couch edges should be considered if an improvement in plan quality or delivery time can be achieved.

  3. Extended Remediation of Sleep Deprived-Induced Working Memory Deficits Using fMRI-guided Transcranial Magnetic Stimulation

    Science.gov (United States)

    Luber, Bruce; Steffener, Jason; Tucker, Adrienne; Habeck, Christian; Peterchev, Angel V.; Deng, Zhi-De; Basner, Robert C.; Stern, Yaakov; Lisanby, Sarah H.

    2013-01-01

    Study Objectives: We attempted to prevent the development of working memory (WM) impairments caused by sleep deprivation using fMRI-guided repetitive transcranial magnetic stimulation (rTMS). Novel aspects of our fMRI-guided rTMS paradigm included the use of sophisticated covariance methods to identify functional networks in imaging data, and the use of fMRI-targeted rTMS concurrent with task performance to modulate plasticity effects over a longer term. Design: Between-groups mixed model. Setting: TMS, MRI, and sleep laboratory study. Participants: 27 subjects (13 receiving Active rTMS, and 14 Sham) completed the sleep deprivation protocol, with another 21 (10 Active, 11 Sham) non-sleep deprived subjects run in a second experiment. Interventions: Our previous covariance analysis had identified a network, including occipital cortex, which demonstrated individual differences in resilience to the deleterious effects of sleep deprivation on WM performance. Five Hz rTMS was applied to left lateral occipital cortex while subjects performed a WM task during 4 sessions over the course of 2 days of total sleep deprivation. Measurements and Results: At the end of the sleep deprivation period, Sham sleep deprived subjects exhibited degraded performance in the WM task. In contrast, those receiving Active rTMS did not show the slowing and lapsing typical in sleep deprivation, and instead performed similarly to non- sleep deprived subjects. Importantly, the Active sleep deprivation group showed rTMS-induced facilitation of WM performance a full 18 hours after the last rTMS session. Conclusions: Over the course of sleep deprivation, these results indicate that rTMS applied concurrently with WM task performance affected neural circuitry involved in WM to prevent its full impact. Citation: Luber B; Steffener J; Tucker A; Habeck C; Peterchev AV; Deng ZD; Basner RC; Stern Y; Lisanby SH. Extended remediation of sleep deprived-induced working memory deficits using fMRI-guided

  4. The application of hyperthermia in regional chemotherapy.

    Science.gov (United States)

    Di Filippo, F; Anzà, M; Rossi, C R; Cavaliere, F; Botti, C; Lise, M; Garinei, R; Giannarelli, D; Vasselli, S; Zupi, G; Cavaliere, R

    1998-01-01

    To evaluate the role of hyperthermia combined with chemotherapy in the loco-regional treatment of tumors, a retrospective analysis was done with 228 limb melanoma patients treated with hyperthermic antiblastic perfusion (HAP). A series of treatment- and tumor-related prognostic factors was analyzed to establish their influence on tumor response, loco-regional control, and survival. Concerning tumor response, the logistic model showed that the number of lesions and the minimal tumor temperature (min T) maintained their individual predictive values (P < 0.000001 and P = 0.04, respectively). For loco-regional control, only the number of lesions had a significant predictive value. No direct correlation was found between the treatment-related variables and loco-regional control. However, the 5-year survival rate was significantly higher for patients who achieved a complete response (CR) (51.5%, P = 0.0033) as compared to those who did not (33.3%), providing indirect evidence of the role of the treatment. Multivariate analysis showed that both disease-free and overall survival are strongly influenced by numerous clinical variables and the min T always maintained its significance. When analyzing the subgroup of 119 patients evaluable for tumor response, the Cox model selected the tumor response as the dominant factor for both disease-free and overall survival. These data seem to demonstrate that the optimization of treatment parameters is crucial in determining the CR rate, which, in turn, positively affects the disease outcome. HAP is the treatment of choice for recurrent limb melanoma, and hyperthermia plays an important role in exploiting the efficacy of this technique.

  5. A thermocouple thermometry system for ultrasound hyperthermia

    International Nuclear Information System (INIS)

    Ozarka, M.; Gharakhani, A.; Magin, R.; Cain, C.

    1984-01-01

    A thermometry system designed to be used in the treatment of cancer by ultrasound hyperthermia is described. The system monitors tumor temperatures using 16 type T (copper-constantan) thermocouples and is controlled by a 12 MHz Intel 8031 microcomputer. An analog circuit board contains the thermocouple amplifiers, an analog multiplexer, scaling circuitry, and an analog to digital converter. A digital board contains the Intel 8031, program memory, data memory, as well as circuitry for control and data communications. Communication with the hyperthermia system control computer is serially by RS-232 with selectable baud rate. Since the thermocouple amplifiers may have slight differences in gain and offset, a calibrated offset is added to a lookup table value to obtain the proper display temperature to within +- 0.1 0 C. The calibration routine, implemented in software, loads a nonvolatile random access memory chip with the proper offset values based on the outputs of each thermocouple channel at known temperatures which bracket a range of interest

  6. Heating efficiency in magnetic nanoparticle hyperthermia

    International Nuclear Information System (INIS)

    Deatsch, Alison E.; Evans, Benjamin A.

    2014-01-01

    Magnetic nanoparticles for hyperthermic treatment of cancers have gained significant attention in recent years. In magnetic hyperthermia, three independent mechanisms result in thermal energy upon stimulation: Néel relaxation, Brownian relaxation, and hysteresis loss. The relative contribution of each is strongly dependent on size, shape, crystalline anisotropy, and degree of aggregation or agglomeration of the nanoparticles. We review the effects of each of these physical mechanisms in light of recent experimental studies and suggest routes for progress in the field. Particular attention is given to the influence of the collective behaviors of nanoparticles in suspension. A number of recent studies have probed the effect of nanoparticle concentration on heating efficiency and have reported superficially contradictory results. We contextualize these studies and show that they consistently indicate a decrease in magnetic relaxation time with increasing nanoparticle concentration, in both Brownian- and Néel-dominated regimes. This leads to a predictable effect on heating efficiency and alleviates a significant source of confusion within the field. - Highlights: • Magnetic nanoparticle hyperthermia. • Heating depends on individual properties and collective properties. • We review recent studies with respect to loss mechanisms. • Collective behavior is a key source of confusion in the field. • We contextualize recent studies to elucidate consistencies and alleviate confusion

  7. Clinical outcome following a low-suspicion multiparametric prostate MRI or benign MRI-guided biopsy to detect prostate cancer

    DEFF Research Database (Denmark)

    Boesen, Lars; Nørgaard, Nis; Løgager, Vibeke

    2017-01-01

    follow-up [132/156 (85%)] had decreasing levels of prostate-specific-antigen and could be monitored in primary care. CONCLUSION: A low-suspicion MRI in men with prior negative systematic biopsies has a high negative predictive value in ruling out longer term significant cancer. Therefore, immediate...... repeated biopsies are of limited clinical value and could be avoided even if prostate-specific-antigen levels are persistently elevated.......PURPOSE: To assess the future risk of detecting significant prostate cancer following either a low-suspicion MRI or suspicious MRI with benign MRI-guided biopsies in men with prior negative systematic biopsies. MATERIALS AND METHODS: 289 prospectively enrolled men underwent MRI followed by repeated...

  8. Full automatic fiducial marker detection on coil arrays for accurate instrumentation placement during MRI guided breast interventions

    Science.gov (United States)

    Filippatos, Konstantinos; Boehler, Tobias; Geisler, Benjamin; Zachmann, Harald; Twellmann, Thorsten

    2010-02-01

    With its high sensitivity, dynamic contrast-enhanced MR imaging (DCE-MRI) of the breast is today one of the first-line tools for early detection and diagnosis of breast cancer, particularly in the dense breast of young women. However, many relevant findings are very small or occult on targeted ultrasound images or mammography, so that MRI guided biopsy is the only option for a precise histological work-up [1]. State-of-the-art software tools for computer-aided diagnosis of breast cancer in DCE-MRI data offer also means for image-based planning of biopsy interventions. One step in the MRI guided biopsy workflow is the alignment of the patient position with the preoperative MR images. In these images, the location and orientation of the coil localization unit can be inferred from a number of fiducial markers, which for this purpose have to be manually or semi-automatically detected by the user. In this study, we propose a method for precise, full-automatic localization of fiducial markers, on which basis a virtual localization unit can be subsequently placed in the image volume for the purpose of determining the parameters for needle navigation. The method is based on adaptive thresholding for separating breast tissue from background followed by rigid registration of marker templates. In an evaluation of 25 clinical cases comprising 4 different commercial coil array models and 3 different MR imaging protocols, the method yielded a sensitivity of 0.96 at a false positive rate of 0.44 markers per case. The mean distance deviation between detected fiducial centers and ground truth information that was appointed from a radiologist was 0.94mm.

  9. MRI follow-up after concordant, histologically benign diagnosis of breast lesions sampled by MRI-guided biopsy.

    Science.gov (United States)

    Li, Jie; Dershaw, D David; Lee, Carol H; Kaplan, Jennifer; Morris, Elizabeth A

    2009-09-01

    Follow-up MRI can be useful to confirm a benign diagnosis after MRI-guided breast biopsy. This retrospective study was undertaken to evaluate appropriate timing and imaging interpretation for the initial follow-up MRI when a benign, concordant histology is obtained using MRI-guided breast biopsy. Retrospective review was performed of 177 lesions visualized only by MRI in 172 women who underwent 9-gauge, vacuum-assisted core biopsy and marker placement with imaging-concordant benign histology. All underwent follow-up MRI within 12 months. Timing of the follow-up study, change in size, results of second biopsy if performed, and distance of localizing marker to the lesion on the follow-up study were recorded. At initial follow-up, 155 lesions were decreased or gone, 14 lesions were stable, and eight were enlarged. Seventeen (9.6%, 17/177) lesions underwent a second biopsy, including six enlarging, 10 stable, and one decreasing. Of these, four were malignant. Enlargement was seen in two carcinomas at 6 and 12 months. Two carcinomas, one stable at 2 months and another stable at 3 and 11 months, were rebiopsied because of suspicion of a missed lesion in the former and worrisome mammographic and sonographic changes in the latter. The distance of the marker from the lesion on follow-up did not correlate with biopsy accuracy. Follow-up MRI did not detect missed cancers because of lesion enlargement before 6 months after biopsy; two of four missed cancers were stable. The localizing marker can deploy away from the target despite successful sampling.

  10. Effects of hyperthermia, radiotherapy and thermoradiotherapy on tumor microvasculature

    International Nuclear Information System (INIS)

    Fujiwara, Kouji

    1987-01-01

    The therapeutic effects of hyperthermia (immersion of tumor-bearing leg in a water bath at 46 deg C for 60 min), radiotherapy (500 rad or 1000 rad) and thermoradiotherapy on VX-2 tumors of the rabbits were studied morphologically. Especially, vascular morphological changes and vascular permeability to ferritin after treatment were investigated by electron microscopy. As assessed by decrease in tumor volume, local hyperthermia potentiated the destructive effect of radiotherapy. The light microscopic pictures invariably suggested prolonged necrotic tendency of tumor cells following thermoradiotherapy. Electron microscopically, 1 day and 3 days after thermoradiotherapy, small blood vessels in the tumors showed swelling and protrusion of endothelial cells in the lumen. Similar morphological changes were obtained only at 3 days after radiotherapy. When vascular permeability to ferritin was examined by electron microscopy, an increase in tumor vascular permeability was occured at 1 day after hyperthermia or thermoradiotherapy, while at 3 days after radiotherapy. These results suggest that the early reaction of tumor microvasculature may be a contributing factor to delayed cell death in tumors after hyperthermia or thermoradiotherapy. (author)

  11. Effects of hyperthermia on the hamster immune system

    International Nuclear Information System (INIS)

    Gangavalli, R.; Cain, C.A.; Tompkins, W.A.F.

    1984-01-01

    In previous studies, the authors have shown that hyperthermia can enhance antibody-complement chytotoxicity of hamster and human tumor cells. Moreover, whole body microwave exposure of hamsters resulted in activation of peritoneal macrophages to a viricidal state and transient suppression of natural killer (NK) cell activity. In this study, the authors compare the effects of whole body heating by microwaves or by an environmental chamber (hot air) on the hamster immune system. Microwave exposure (25mW/cm/sup 2/; 1 hr) caused viricidal activation of peritoneal macrophages which resulted in restriction of vaccinia and vesicular stomatitis virs (VSV) growth. However, heating in an environmental chamber (41 0 C; 1 hr) did not activate macrophages to a viricidal state. Both microwave and hot air hyperthermia caused significant augmentation of antibody producing spleen cell response to sheep red blood cells (SRBC), using the Jerne hymolytic plaque assay, four days post exposure and immunization with SRBC. Natural killer spleen cell cytotoxicity was suppressed by microwave and hot air hyperthermia showing that NK lymphocytes are extremely sensitive to changes in temperature. These alterations in cellular immune response due to hyperthermia could be of significance in treatment of tumors and viral infections

  12. Clinical study of suppository delivery of 5-fluorouracil and pathological effects on metastatic lymph nodes caused by preoperative combined treatment with radiation, intraluminal hyperthermia and 5-fluorouracil suppository in rectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tamura, Takaaki [Kyoto Prefectural Univ. of Medicine (Japan)

    1997-11-01

    Preoperative combined treatment with radiation, intraluminal hyperthermia, and 5-fluorouracil (5-FU) suppository has been reported effective in shrinking locally advanced rectal cancers and facilitating subsequent surgery. Suppository and intravenous 5-FU administration were compared with respect to tissue concentrations in rectal cancer cases. Just before the operation patients received 100 mg of 5-FU via suppository or intravenously. Portal and systemic blood, tumor tissue, normal mucosa and muscle layer separately at 5, 10, 15 cm in the oral direction from the tumor and the pararectal lymph node were harvested for high-performance liquid chromatography determination of 5-FU concentrations. Rectal 5-FU concentrations were significantly higher in the suppository cases compared with the intravenously administrated ones. Suppository distributed more 5-FU at pararectal lymph nodes than intravenous injection. This fact revealed 5-FU suppositories to be a useful drug delivery system for rectal cancer. The pathological effects on metastatic lymph nodes caused by combined treatment were evaluated in 22 cases. Normal lymph nodes showed congestion only. Fibrotic and necrotic changes were characteristic of damaged metastatic areas. In 6 cases (27.3%), no metastatic cells were detected on fibrotically changed areas. The down staging of the lymph node metastatic factor was carried out by preoperative combined treatment. High concentrations of 5-FU at mucosa could suggest the usefulness of 5-FU suppository administration just before operation for prevention of suture-line implantation. (author)

  13. Clinical study of suppository delivery of 5-fluorouracil and pathological effects on metastatic lymph nodes caused by preoperative combined treatment with radiation, intraluminal hyperthermia and 5-fluorouracil suppository in rectal cancer

    International Nuclear Information System (INIS)

    Tamura, Takaaki

    1997-01-01

    Preoperative combined treatment with radiation, intraluminal hyperthermia, and 5-fluorouracil (5-FU) suppository has been reported effective in shrinking locally advanced rectal cancers and facilitating subsequent surgery. Suppository and intravenous 5-FU administration were compared with respect to tissue concentrations in rectal cancer cases. Just before the operation patients received 100 mg of 5-FU via suppository or intravenously. Portal and systemic blood, tumor tissue, normal mucosa and muscle layer separately at 5, 10, 15 cm in the oral direction from the tumor and the pararectal lymph node were harvested for high-performance liquid chromatography determination of 5-FU concentrations. Rectal 5-FU concentrations were significantly higher in the suppository cases compared with the intravenously administrated ones. Suppository distributed more 5-FU at pararectal lymph nodes than intravenous injection. This fact revealed 5-FU suppositories to be a useful drug delivery system for rectal cancer. The pathological effects on metastatic lymph nodes caused by combined treatment were evaluated in 22 cases. Normal lymph nodes showed congestion only. Fibrotic and necrotic changes were characteristic of damaged metastatic areas. In 6 cases (27.3%), no metastatic cells were detected on fibrotically changed areas. The down staging of the lymph node metastatic factor was carried out by preoperative combined treatment. High concentrations of 5-FU at mucosa could suggest the usefulness of 5-FU suppository administration just before operation for prevention of suture-line implantation. (author)

  14. MRI-Guided Intervention for Breast Lesions Using the Freehand Technique in a 3.0-T Closed-Bore MRI Scanner: Feasibility and Initial Results

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hye Young [Department of Radiology, Gyeongsang National University Hospital, Jinju 660-702 (Korea, Republic of); Kim, Sun Mi; Jang, Mijung; Yun, Bo La [Department of Radiology, Seoul National University Bundang Hospital, Seongnam 463-707 (Korea, Republic of); Kim, Sung-Won; Kang, Eunyoung [Department of Surgery, Seoul National University Bundang Hospital, Seongnam 463-707 (Korea, Republic of); Park, So Yeon [Department of Pathology, Seoul National University Bundang Hospital, Seongnam 463-707 (Korea, Republic of); Moon, Woo Kyung [Department of Radiology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul 110-744 (Korea, Republic of); Ko, Eun Sook [Department of Radiology, Samsung Medical Center, Seoul 135-710 (Korea, Republic of)

    2013-07-01

    To report the feasibility of magnetic resonance imaging (MRI)-guided intervention for diagnosing suspicious breast lesions detectable by MRI only, using the freehand technique with a 3.0-T closed-bore MRI scanner. Five women with 5 consecutive MRI-only breast lesions underwent MRI-guided intervention: 3 underwent MRI-guided needle localization and 2, MRI-guided vacuum-assisted biopsy. The interventions were performed in a 3.0-T closed-bore MRI system using a dedicated phased-array breast coil with the patients in the prone position; the freehand technique was used. Technical success and histopathologic outcome were analyzed. MRI showed that four lesions were masses (mean size, 11.5 mm; range, 7-18 mm); and 1, a nonmass-like enhancement (maximum diameter, 21 mm). The locations of the lesions with respect to the breast with index cancer were as follows: different quadrant, same breast - 3 cases; same quadrant, same breast - 1 case; and contralateral breast - 1 case. Histopathologic evaluation of the lesions treated with needle localization disclosed perilobular hemangioma, fibrocystic change, and fibroadenomatous change. The lesions treated with vacuum-assisted biopsy demonstrated a radial scar and atypical apocrine hyperplasia. Follow-up MRI after 2-7 months (mean, 4.6 months) confirmed complete lesion removal in all cases. MRI-guided intervention for breast lesions using the freehand technique with a 3.0-T closed-bore MRI scanner is feasible and accurate for diagnosing MRI-only lesions.

  15. Lobular neoplasia detected in MRI-guided core biopsy carries a high risk for upgrade: a study of 63 cases from four different institutions

    Science.gov (United States)

    Khoury, Thaer; Kumar, Prasanna R; Li, Zaibo; Karabakhtsian, Rouzan G; Sanati, Souzan; Chen, Xiwei; Wang, Dan; Liu, Song; Reig, Beatriu

    2017-01-01

    There are certain criteria to recommend surgical excision for lobular neoplasia diagnosed in mammographically detected core biopsy. The aims of this study are to explore the rate of upgrade of lobular neoplasia detected in magnetic resonance imaging (MRI)-guided biopsy and to investigate the clinicopathological and radiological features that could predict upgrade. We reviewed 1655 MRI-guided core biopsies yielding 63 (4%) cases of lobular neoplasia. Key clinical features were recorded. MRI findings including mass vs non-mass enhancement and the reason for biopsy were also recorded. An upgrade was defined as the presence of invasive carcinoma or ductal carcinoma in situ in subsequent surgical excision. The overall rate of lobular neoplasia in MRI-guided core biopsy ranged from 2 to 7%, with an average of 4%. A total of 15 (24%) cases had an upgrade, including 5 cases of invasive carcinoma and 10 cases of ductal carcinoma in situ. Pure lobular neoplasia was identified in 34 cases, 11 (32%) of which had upgrade. In this group, an ipsilateral concurrent or past history of breast cancer was found to be associated with a higher risk of upgrade (6/11, 55%) than contralateral breast cancer (1 of 12, 8%; P = 0.03). To our knowledge, this is the largest series of lobular neoplasia diagnosed in MRI-guided core biopsy. The incidence of lobular neoplasia is relatively low. Lobular neoplasia detected in MRI-guided biopsy carries a high risk for upgrade warranting surgical excision. However, more cases from different types of institutions are needed to verify our results. PMID:26564004

  16. MRI-Guided Intervention for Breast Lesions Using the Freehand Technique in a 3.0-T Closed-Bore MRI Scanner: Feasibility and Initial Results

    International Nuclear Information System (INIS)

    Choi, Hye Young; Kim, Sun Mi; Jang, Mijung; Yun, Bo La; Kim, Sung-Won; Kang, Eunyoung; Park, So Yeon; Moon, Woo Kyung; Ko, Eun Sook

    2013-01-01

    To report the feasibility of magnetic resonance imaging (MRI)-guided intervention for diagnosing suspicious breast lesions detectable by MRI only, using the freehand technique with a 3.0-T closed-bore MRI scanner. Five women with 5 consecutive MRI-only breast lesions underwent MRI-guided intervention: 3 underwent MRI-guided needle localization and 2, MRI-guided vacuum-assisted biopsy. The interventions were performed in a 3.0-T closed-bore MRI system using a dedicated phased-array breast coil with the patients in the prone position; the freehand technique was used. Technical success and histopathologic outcome were analyzed. MRI showed that four lesions were masses (mean size, 11.5 mm; range, 7-18 mm); and 1, a nonmass-like enhancement (maximum diameter, 21 mm). The locations of the lesions with respect to the breast with index cancer were as follows: different quadrant, same breast - 3 cases; same quadrant, same breast - 1 case; and contralateral breast - 1 case. Histopathologic evaluation of the lesions treated with needle localization disclosed perilobular hemangioma, fibrocystic change, and fibroadenomatous change. The lesions treated with vacuum-assisted biopsy demonstrated a radial scar and atypical apocrine hyperplasia. Follow-up MRI after 2-7 months (mean, 4.6 months) confirmed complete lesion removal in all cases. MRI-guided intervention for breast lesions using the freehand technique with a 3.0-T closed-bore MRI scanner is feasible and accurate for diagnosing MRI-only lesions

  17. Hyperthermia stimulates HIV-1 replication.

    Directory of Open Access Journals (Sweden)

    Ferdinand Roesch

    Full Text Available HIV-infected individuals may experience fever episodes. Fever is an elevation of the body temperature accompanied by inflammation. It is usually beneficial for the host through enhancement of immunological defenses. In cultures, transient non-physiological heat shock (42-45°C and Heat Shock Proteins (HSPs modulate HIV-1 replication, through poorly defined mechanisms. The effect of physiological hyperthermia (38-40°C on HIV-1 infection has not been extensively investigated. Here, we show that culturing primary CD4+ T lymphocytes and cell lines at a fever-like temperature (39.5°C increased the efficiency of HIV-1 replication by 2 to 7 fold. Hyperthermia did not facilitate viral entry nor reverse transcription, but increased Tat transactivation of the LTR viral promoter. Hyperthermia also boosted HIV-1 reactivation in a model of latently-infected cells. By imaging HIV-1 transcription, we further show that Hsp90 co-localized with actively transcribing provirus, and this phenomenon was enhanced at 39.5°C. The Hsp90 inhibitor 17-AAG abrogated the increase of HIV-1 replication in hyperthermic cells. Altogether, our results indicate that fever may directly stimulate HIV-1 replication, in a process involving Hsp90 and facilitation of Tat-mediated LTR activity.

  18. Magnetomotive Optical Coherence Elastography for Magnetic Hyperthermia Dosimetry Based on Dynamic Tissue Biomechanics

    Science.gov (United States)

    Huang, Pin-Chieh; Pande, Paritosh; Ahmad, Adeel; Marjanovic, Marina; Spillman, Darold R.; Odintsov, Boris; Boppart, Stephen A.

    2016-01-01

    Magnetic nanoparticles (MNPs) have been used in many diagnostic and therapeutic biomedical applications over the past few decades to enhance imaging contrast, steer drugs to targets, and treat tumors via hyperthermia. Optical coherence tomography (OCT) is an optical biomedical imaging modality that relies on the detection of backscattered light to generate high-resolution cross-sectional images of biological tissue. MNPs have been utilized as imaging contrast and perturbative mechanical agents in OCT in techniques called magnetomotive OCT (MM-OCT) and magnetomotive elastography (MM-OCE), respectively. MNPs have also been independently used for magnetic hyperthermia treatments, enabling therapeutic functions such as killing tumor cells. It is well known that the localized tissue heating during hyperthermia treatments result in a change in the biomechanical properties of the tissue. Therefore, we propose a novel dosimetric technique for hyperthermia treatment based on the viscoelasticity change detected by MM-OCE, further enabling the theranostic function of MNPs. In this paper, we first review the basic principles and applications of MM-OCT, MM-OCE, and magnetic hyperthermia, and present new preliminary results supporting the concept of MM-OCE-based hyperthermia dosimetry. PMID:28163565

  19. TU-H-BRA-08: The Design and Characteristics of a Novel Compact Linac-Based MRI Guided Radiation Therapy (MR-IGRT) System

    International Nuclear Information System (INIS)

    Mutic, S; Low, D; Chmielewski, T; Fought, G; Hernandez, M; Kawrakow, I; Sharma, A; Shvartsman, S; Dempsey, J

    2016-01-01

    Purpose: To describe the design and characteristics of a novel linac-based MRI guided radiation therapy system that addresses RF and magnetic field interference and that can be housed in conventional radiotherapy vaults. Methods: The MR-IGRT system will provide simultaneous MR imaging combined with both simple (3D) and complex (IMRT, SBRT, SRS) techniques. The system is a combination of a) double-donut split solenoidal superconducting 0.345T MRI; and b) a 90 cm isocenter ring-gantry mounted 6MV, flattening filter-free linac coupled with a stacked doubly-focused multileaf collimator with 4 mm resolution. A novel RF shielding and absorption technology was developed to isolate the beam generating RF emissions from the MR, while a novel magnetic shielding sleeve system was developed to place the magnetic field-sensitive components in low-magnetic field regions. The system design produces high spatial resolution radiation beams with state-of-the art radiation dose characteristics and simultaneous MR imaging. Results: Prototype testing with a spectrum analyzer has demonstrated complete elimination of linac RF inside the treatment room. The magnetic field inside of the magnetic shielding was well below the specification, allowing the linear accelerator to operate normally. A novel on-gantry shimming system maintained < 25 ppm magnetic field homogeneity over a 45 cm spherical field of view for all gantry angles. Conclusion: The system design demonstrates the feasibility coupling a state-of-the art linac system with a 0.345T MRI, enabling highly conformal radiation therapy with simultaneous MR image guidance. S. Mutic’s employer (Washington University) has grant with ViewRay; D. Low is former ViewRay scientific advisory board member (ended October 2015); T. Chmielewski, G. Fought, M. Hernandez, I. Kawrakow, A. Sharma, S. Shvartsman, J. Dempsey are employees of ViewRay with stock options (Dempsey has leadership role and Dempsey/Kawrakow have stock).

  20. TU-H-BRA-08: The Design and Characteristics of a Novel Compact Linac-Based MRI Guided Radiation Therapy (MR-IGRT) System

    Energy Technology Data Exchange (ETDEWEB)

    Mutic, S [Washington University School of Medicine, Saint Louis, MO (United States); Low, D [UCLA, Los Angeles, CA (United States); Chmielewski, T; Fought, G; Hernandez, M; Kawrakow, I; Sharma, A; Shvartsman, S; Dempsey, J [ViewRay, Inc., Oakwood Village, OH (United States)

    2016-06-15

    Purpose: To describe the design and characteristics of a novel linac-based MRI guided radiation therapy system that addresses RF and magnetic field interference and that can be housed in conventional radiotherapy vaults. Methods: The MR-IGRT system will provide simultaneous MR imaging combined with both simple (3D) and complex (IMRT, SBRT, SRS) techniques. The system is a combination of a) double-donut split solenoidal superconducting 0.345T MRI; and b) a 90 cm isocenter ring-gantry mounted 6MV, flattening filter-free linac coupled with a stacked doubly-focused multileaf collimator with 4 mm resolution. A novel RF shielding and absorption technology was developed to isolate the beam generating RF emissions from the MR, while a novel magnetic shielding sleeve system was developed to place the magnetic field-sensitive components in low-magnetic field regions. The system design produces high spatial resolution radiation beams with state-of-the art radiation dose characteristics and simultaneous MR imaging. Results: Prototype testing with a spectrum analyzer has demonstrated complete elimination of linac RF inside the treatment room. The magnetic field inside of the magnetic shielding was well below the specification, allowing the linear accelerator to operate normally. A novel on-gantry shimming system maintained < 25 ppm magnetic field homogeneity over a 45 cm spherical field of view for all gantry angles. Conclusion: The system design demonstrates the feasibility coupling a state-of-the art linac system with a 0.345T MRI, enabling highly conformal radiation therapy with simultaneous MR image guidance. S. Mutic’s employer (Washington University) has grant with ViewRay; D. Low is former ViewRay scientific advisory board member (ended October 2015); T. Chmielewski, G. Fought, M. Hernandez, I. Kawrakow, A. Sharma, S. Shvartsman, J. Dempsey are employees of ViewRay with stock options (Dempsey has leadership role and Dempsey/Kawrakow have stock).

  1. Quantifying the Combined Effect of Radiation Therapy and Hyperthermia in Terms of Equivalent Dose Distributions

    International Nuclear Information System (INIS)

    Kok, H. Petra; Crezee, Johannes; Franken, Nicolaas A.P.; Stalpers, Lukas J.A.; Barendsen, Gerrit W.; Bel, Arjan

    2014-01-01

    Purpose: To develop a method to quantify the therapeutic effect of radiosensitization by hyperthermia; to this end, a numerical method was proposed to convert radiation therapy dose distributions with hyperthermia to equivalent dose distributions without hyperthermia. Methods and Materials: Clinical intensity modulated radiation therapy plans were created for 15 prostate cancer cases. To simulate a clinically relevant heterogeneous temperature distribution, hyperthermia treatment planning was performed for heating with the AMC-8 system. The temperature-dependent parameters α (Gy −1 ) and β (Gy −2 ) of the linear–quadratic model for prostate cancer were estimated from the literature. No thermal enhancement was assumed for normal tissue. The intensity modulated radiation therapy plans and temperature distributions were exported to our in-house-developed radiation therapy treatment planning system, APlan, and equivalent dose distributions without hyperthermia were calculated voxel by voxel using the linear–quadratic model. Results: The planned average tumor temperatures T90, T50, and T10 in the planning target volume were 40.5°C, 41.6°C, and 42.4°C, respectively. The planned minimum, mean, and maximum radiation therapy doses were 62.9 Gy, 76.0 Gy, and 81.0 Gy, respectively. Adding hyperthermia yielded an equivalent dose distribution with an extended 95% isodose level. The equivalent minimum, mean, and maximum doses reflecting the radiosensitization by hyperthermia were 70.3 Gy, 86.3 Gy, and 93.6 Gy, respectively, for a linear increase of α with temperature. This can be considered similar to a dose escalation with a substantial increase in tumor control probability for high-risk prostate carcinoma. Conclusion: A model to quantify the effect of combined radiation therapy and hyperthermia in terms of equivalent dose distributions was presented. This model is particularly instructive to estimate the potential effects of interaction from different treatment

  2. Predicting thermal history a-priori for magnetic nanoparticle hyperthermia of internal carcinoma

    Science.gov (United States)

    Dhar, Purbarun; Sirisha Maganti, Lakshmi

    2017-08-01

    This article proposes a simplistic and realistic method where a direct analytical expression can be derived for the temperature field within a tumour during magnetic nanoparticle hyperthermia. The approximated analytical expression for thermal history within the tumour is derived based on the lumped capacitance approach and considers all therapy protocols and parameters. The present method is simplistic and provides an easy framework for estimating hyperthermia protocol parameters promptly. The model has been validated with respect to several experimental reports on animal models such as mice/rabbit/hamster and human clinical trials. It has been observed that the model is able to accurately estimate the thermal history within the carcinoma during the hyperthermia therapy. The present approach may find implications in a-priori estimation of the thermal history in internal tumours for optimizing magnetic hyperthermia treatment protocols with respect to the ablation time, tumour size, magnetic drug concentration, field strength, field frequency, nanoparticle material and size, tumour location, and so on.

  3. Assessment of immunomodulating action of combined therapy with UHF-hyperthermia in children with osteogenic sarcoma

    International Nuclear Information System (INIS)

    Neprina, G.S.; Panteleeva, E.S.; Vatin, O.E.; Bizer, V.A.; Bojko, I.N.

    1989-01-01

    The paper is concerned with immunological evaluation of different stages of combined therapy with local UHF-hyperthermia in children with osteogenic sarcoma. Combined therapy (polychemo- and raditherapy) was shown to cause a decrease in the number of immunocompetent cells, to enhance dysbalance of immunoregulatory T-lymphocytes, to weaken T-lymphocyte function on PHA; immunosuppressive action of combined therapy did not depend on a tumor site. The incorporation of UHF-hyperthermia in the therapeutic scheme weakened the manifestations of secondary immunodeficiency, got back to normal structure of T-lymphocyte population. A favorable immunomodulating effect of hyperthermia was more frequently observed in patients with crural bone tumors. The effect of hyperthermia was revealed after direct influence of thermotherapy but it was absent in continuation of combined treatment

  4. Efficiency of lipofection combined with hyperthermia in Lewis lung carcinoma cells and a rodent pleural dissemination model of lung carcinoma.

    Science.gov (United States)

    Okita, Atsushi; Mushiake, Hiroyuki; Tsukuda, Kazunori; Aoe, Motoi; Murakami, Masakazu; Andou, Akio; Shimizu, Nobuyoshi

    2004-06-01

    We have previously reported that hyperthermia at 41 degrees C enhanced lipofection-mediated gene transduction into cultured cells. In this study, we adapted hyperthermia technique to novel cationic liposome (Lipofectamine 2000) mediated gene transfection into Lewis lung carcinoma cells in vitro and in vivo. In vitro, transfection efficiencies were 38.9+/-3.3% by lipofection alone and 52.1+/-2.6% by lipofection with hyperthermia for 30 min, and 62.5+/-5.5% and 81.4+/-3.2% for 1 h, respectively. Hyperthermia significantly enhanced gene transfection efficiency 1.2-1.4 times more than that with lipofection only. We also evaluated the effect of hyperthermia with a pleural dissemination model of lung carcinoma of mice. We developed a model which was well-tolerated with hyperthermia with lipofection by the mice. In spite of repeated treatments, transfection efficiencies were very low and we could not show the augmentation of gene transfection by hyperthermia. Though Lipofectamine 2000 showed strong gene transduction effect and hyperthermia augmented its effect in vitro, further evaluation is needed to adapt both techniques in vivo.

  5. Hormonal, Biochemical and Haematological Changes in Response to Acute Hyperthermia in Rabbits

    International Nuclear Information System (INIS)

    Zahran, N.A.R.M.

    2004-01-01

    Today, hyperthermia plays a significant role in the evidence-based on treatment of cancer patients. Such promising endeavor is due to the fact that neoplastic cells are more heat sensitive than normal cells. the prospect of using hyperthermia alone to treat cancer tumours is appealing because hyperthermia is a physical treatment and so would have fewer side effects than chemotherapy or radiotherapy and, it could be used in combination with these therapeutic approaches. much more consistent evidence has been obtained experimentally, and continuing clinical interest has been encouraged by confirmation that, at relatively low temperature (37-41.5 C), heat enhances cell growth and may well enhance also the growth and proliferation of tumours, while above 45 C heat begins to damage both normal and malignant cells in both animal and human. So, the goal is to achieve a selective temperature elevation between 42-45 C at the tumour site while maintaining healthy tissue temperatures in a physiological save range.This study was undertaken to investigate the effect of acute whole body hyperthermia , (WBH) (rectal temperature 43 c) on biochemical , hormonal and haematological changes in normal healthy local strain (baladi) rabbits.The thermal late effects (recovery) at 24 hr-post whole body hyperthermia was also undertaken , in the attempt to evaluate the degree of safety , when hyperthermia is applied in the clinic for treating cancer and other diseases

  6. Thermoseeds for interstitial magnetic hyperthermia: from bioceramics to nanoparticles

    International Nuclear Information System (INIS)

    Baeza, A; Arcos, D; Vallet-Regí, M

    2013-01-01

    The development of magnetic materials for interstitial hyperthermia treatment of cancer is an ever evolving research field which provides new alternatives to antitumoral therapies. The development of biocompatible magnetic materials has resulted in new biomaterials with multifunctional properties, which are able to adapt to the complex scenario of tumoral processes. Once implanted or injected in the body, magnetic materials can behave as thermoseeds under the effect of AC magnetic fields. Magnetic bioceramics aimed to treat bone tumors and magnetic nanoparticles are among the most studied thermoseeds, and supply different solutions for the different scenarios in cancerous processes. This paper reviews some of the biomaterials used for bone cancer treatment and skeletal reinforcing, as well as the more complex topic of magnetic nanoparticles for intracellular targeting and hyperthermia. (topical review)

  7. Radiation plus local hyperthermia versus radiation plus the combination of local and whole-body hyperthermia in canine sarcomas

    International Nuclear Information System (INIS)

    Thrall, Donald E.; Prescott, Deborah M.; Samulski, Thaddeus V.; Rosner, Gary L.; Denman, David L.; Legorreta, Roberto L.; Dodge, Richard K.; Page, Rodney L.; Cline, J. Mark; Lee Jihjong; Case, Beth C.; Evans, Sydney M.; Oleson, James R.; Dewhirst, Mark W.

    1996-01-01

    Purpose: The purpose of this study was to assess the effect of increasing intratumoral temperatures by the combination of local hyperthermia (LH) and whole body hyperthermia (WBH) on the radiation response of canine sarcomas. Methods and Materials: Dogs with spontaneous soft tissue sarcomas and no evidence of metastasis were randomized to be treated with radiation combined with either LH alone or LH + WBH. Dogs were accessioned for treatment at two institutions. The radiation dose was 56.25 Gy, given in 25 2.25 Gy daily fractions. Two hyperthermia treatments were given; one during the first and one during the last week of treatment. Dogs were evaluated after treatment for local recurrence, metastasis, and complications. Results: Sixty-four dogs were treated between 1989 and 1993. The use of LH+WBH resulted in statistically significant increases in the low and middle regions of the temperature distributions. The largest increase was in the low temperatures with median CEM 43 T90 values of 4 vs. 49 min for LH vs. LH + WBH, respectively (p < 0.001). There was no difference in duration of local tumor control between hyperthermia groups (p = 0.59). The time to metastasis was shorter for dogs receiving LH + WBH (p = 0.02); the hazard ratio for metastatic disease for dogs in the LH + WBH group was 2.5 (95% confidence interval, 1.2-5.4) with respect to dogs in the LH group. Complications were greater in larger tumors and in tumors treated with LH + WBH. Conclusion: The combination of LH + WBH with radiation therapy, as described herein, was not associated with an increase in local tumor control in comparison to use of LH with radiation therapy. The combination of LH + WBH also appeared to alter the biology of the metastatic process and was associated with more complications than LH. We identified no rationale for further study of LH + WBH in combination with radiation for treatment of solid tumors

  8. Preferential radiosensitization of human prostatic carcinoma cells by mild hyperthermia

    International Nuclear Information System (INIS)

    Ryu, Samuel; Brown, Stephen L.; Kim, Sang-Hie; Khil, Mark S.; Kim, Jae Ho

    1996-01-01

    Purpose: Recent cell culture studies by us and others suggest that some human carcinoma cells are more sensitive to heat than are rodent cells following mild hyperthermia. In studying the cellular mechanism of enhanced thermosensitivity of human tumor cells to hyperthermia, prostatic carcinoma cells of human origin were found to be more sensitive to mild hyperthermia than other human cancer cells. The present study was designed to determine the magnitude of radiosensitization of human prostatic carcinoma cells by mild hyperthermia and to examine whether the thermal radiosensitization is related to the intrinsic thermosensitivity of cancer cells. Methods and Materials: Two human prostatic carcinoma cell lines (DU-145 and PC-3) and other carcinoma cells of human origin, in particular, colon (HT-29), breast (MCF-7), lung (A-549), and brain (U-251) were exposed to temperatures of 40-41 deg. C. Single acute dose rate radiation and fractionated radiation were combined with mild hyperthermia to determine thermal radiosensitization. The end point of the study was the colony-forming ability of single-plated cells. Results: DU-145 and PC-3 cells were found to be exceedingly thermosensitive to 41 deg. C for 24 h, relative to other cancer cell lines. Ninety percent of the prostatic cancer cells were killed by a 24 h heat exposure. Prostatic carcinoma cells exposed to a short duration of heating at 41 deg. C for 2 h resulted in a substantial enhancement of radiation-induced cytotoxicity. The thermal enhancement ratios (TERs) of single acute dose radiation following heat treatment 41 deg. C for 2 h were 2.0 in DU-145 cells and 1.4 in PC-3 cells. The TERs of fractionated irradiation combined with continuous heating at 40 deg. C were similarly in the range of 2.1 to 1.4 in prostate carcinoma cells. No significant radiosensitization was observed in MCF-7 and HT-29 cells under the same conditions. Conclusion: The present data suggest that a significant radiosensitization of

  9. The clinical rationale for MRI-guided radiotherapy : the dawn of a new era

    NARCIS (Netherlands)

    Kerkhof, E.M.

    2010-01-01

    Current radiotherapy treatment machines use the treatment beam or the integrated cone-beam computed tomography (CBCT) functionality for patient positioning based on bony structures or implanted tumour markers. The University Medical Center Utrecht, in cooperation with Elekta and Philips, is

  10. The individual and combined effects of γ rays and hyperthermia on the development of embryonic brains

    International Nuclear Information System (INIS)

    Yang Yepeng; Ruan Ming; Liu Jingyuan; Hong Min; Lu Chunlin

    2000-01-01

    Objective: To observe the individual and combined effects of exposure to γ rays and hyperthermia on the development of embryonic brains. Methods: the pregnant LACA mice were exposed to 1.0 Gy 60 Co-γ rays, 42 degree C hyperthermia for 10 minutes or the two treatments combined together on day 9 of pregnancy. The females were sacrificed on day 18 of pregnancy and the fetuses were gained by cesarean section. The appearance of fetuses was observed and, then, the weight of fetal brains, the cell number of whole brains, the contents of nucleic acid and protein in brain tissue and the activity of acetylcholine esterase (AChE) in brain tissue as a marker for cholinergic neurons were determined. Results: Nervous tube defects did not occur in all groups. Compared with the control group, all the indices determined significantly declined in the radiation group while the cell number of whole brains and the AChE activity in brain tissue significantly decreased in the hyperthermia group. In the group of hyperthermia in advance, 4 hours later, followed by exposure to radiation, the AChE activity in brain tissue was significantly higher than the single radiation group. In the group of prior radiation exposure, 4 hours later, followed by hyperthermia, all the indices did not present significant difference from the single radiation group. Conclusion: The effects of 42 degree C hyperthermia for 10 minutes on the development of mouse embryo's brains are much weaker than 1.0 Gy γ radiation. It seems that the hyperthermia in advance can induce mouse fetuses to produce the cross adaptability to the following exposure to radiation. Exposure to γ radiation followed by hyperthermia does not present and additive action or a synergistic action

  11. TU-AB-BRA-11: Indications for Online Adaptive Radiotherapy Based On Dosimetric Consequences of Interfractional Pancreas-To-Duodenum Motion in MRI-Guided Pancreatic Radiotherapy

    International Nuclear Information System (INIS)

    Mittauer, K; Rosenberg, S; Geurts, M; Bassetti, M; Wojcieszynski, A; Harari, P; Labby, Z; Hill, P; Paliwal, B; Bayouth, J; Chen, I; Henke, L; Kashani, R; Parikh, P; Olsen, J

    2016-01-01

    Purpose: Dose limiting structures, such as the duodenum, render the treatment of pancreatic cancer challenging. In this multi-institutional study, we assess dosimetric differences caused by interfraction pancreas-to-duodenum motion using MR-IGRT to determine the potential impact of adaptive replanning. Methods: Ten patients from two institutions undergoing MRI-guided radiotherapy with conventional fractionation (n=5) or SBRT (n=5) for pancreatic cancer were included. Initial plans were limited by duodenal dose constraints of 50 Gy (0.5 cc)/31 Gy (0.1 cc) for conventional/SBRT with prescriptions of 30 Gy/5 fractions (SBRT) and 40–50 Gy/25 fractions (conventional). Daily volumetric MR images were acquired under treatment conditions on a clinical MR-IGRT system. The correlation was assessed between interfractional GTV-to-duodenum positional variation and daily recalculations of duodenal dose metrics. Positional variation was quantified as the interfraction difference in Hausdorff distance from simulation baseline (ΔHD) between the GTV and proximal duodenal surface, or volume overlap between GTV and duodenum for cases with HD_0=0 (GTV abutting duodenum). Adaptation was considered indicated when daily positional variations enabled dose escalation to the target while maintaining duodenal constraints. Results: For fractions with ΔHD>0 (n=14, SBRT only), the mean interfraction duodenum dose decrease from simulation to treatment was 44±53 cGy (maximum 136 cGy). A correlation was found between ΔHD and dosimetric difference (R"2=0.82). No correlation was found between volume of overlap and dosimetric difference (R"2=0.31). For 89% of fractions, the duodenum remained overlapped with the target and the duodenal dose difference was negligible. The maximum observed indication for adaptation was for interfraction ΔHD=11.6 mm with potential for adaptive dose escalation of 136 cGy. Conclusion: This assessment showed that Hausdorff distance was a reasonable metric to use to

  12. TU-AB-BRA-11: Indications for Online Adaptive Radiotherapy Based On Dosimetric Consequences of Interfractional Pancreas-To-Duodenum Motion in MRI-Guided Pancreatic Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Mittauer, K; Rosenberg, S; Geurts, M; Bassetti, M; Wojcieszynski, A; Harari, P; Labby, Z; Hill, P; Paliwal, B; Bayouth, J [University of Wisconsin, School of Medicine and Public Health, Madison, WI (United States); Chen, I; Henke, L; Kashani, R; Parikh, P [Washington University School of Medicine, St. Louis, MO (United States); Olsen, J [University of Colorado- Denver, Aurora, CO (United States)

    2016-06-15

    Purpose: Dose limiting structures, such as the duodenum, render the treatment of pancreatic cancer challenging. In this multi-institutional study, we assess dosimetric differences caused by interfraction pancreas-to-duodenum motion using MR-IGRT to determine the potential impact of adaptive replanning. Methods: Ten patients from two institutions undergoing MRI-guided radiotherapy with conventional fractionation (n=5) or SBRT (n=5) for pancreatic cancer were included. Initial plans were limited by duodenal dose constraints of 50 Gy (0.5 cc)/31 Gy (0.1 cc) for conventional/SBRT with prescriptions of 30 Gy/5 fractions (SBRT) and 40–50 Gy/25 fractions (conventional). Daily volumetric MR images were acquired under treatment conditions on a clinical MR-IGRT system. The correlation was assessed between interfractional GTV-to-duodenum positional variation and daily recalculations of duodenal dose metrics. Positional variation was quantified as the interfraction difference in Hausdorff distance from simulation baseline (ΔHD) between the GTV and proximal duodenal surface, or volume overlap between GTV and duodenum for cases with HD{sub 0}=0 (GTV abutting duodenum). Adaptation was considered indicated when daily positional variations enabled dose escalation to the target while maintaining duodenal constraints. Results: For fractions with ΔHD>0 (n=14, SBRT only), the mean interfraction duodenum dose decrease from simulation to treatment was 44±53 cGy (maximum 136 cGy). A correlation was found between ΔHD and dosimetric difference (R{sup 2}=0.82). No correlation was found between volume of overlap and dosimetric difference (R{sup 2}=0.31). For 89% of fractions, the duodenum remained overlapped with the target and the duodenal dose difference was negligible. The maximum observed indication for adaptation was for interfraction ΔHD=11.6 mm with potential for adaptive dose escalation of 136 cGy. Conclusion: This assessment showed that Hausdorff distance was a reasonable

  13. Comparison of microwave and magnetic nanoparticle hyperthermia radiosensitization in murine breast tumors

    Science.gov (United States)

    Giustini, Andrew J.; Petryk, Alicia A.; Hoopes, Paul J.

    2011-03-01

    Hyperthermia has been shown to be an effective radiosensitizer. Its utility as a clinical modality has been limited by a minimally selective tumor sensitivity and the inability to be delivered in a tumor-specific manner. Recent in vivo studies (rodent and human) have shown that cancer cell-specific cytotoxicity can be effectively and safely delivered via iron oxide magnetic nanoparticles (mNP) and an appropriately matched noninvasive alternating magnetic field (AMF). To explore the tumor radiosensitization potential of mNP hyperthermia we used a syngeneic mouse breast cancer model, dextran-coated 110 nm hydrodynamic diameter mNP and a 169 kHz / 450 Oe (35.8 kA/m) AMF. Intradermally implanted (flank) tumors (150 +/- 40 mm3) were treated by injection of 0.04 ml mNP (7.5 mg Fe) / cm3 into the tumor and an AMF (35.8 kA/m and 169 kHz) exposure necessary to achieve a CEM (cumulative equivalent minute) thermal dose of 60 (CEM 60). Tumors were treated with mNP hyperthermia (CEM 60), radiation alone (15 Gy, single dose) and in combination. Compared to the radiation and heat alone treatments, the combined treatment resulted in a greater than two-fold increase in tumor regrowth tripling time (tumor treatment efficacy). None of the treatments resulted in significant normal tissue toxicity or morbidity. Studies were also conducted to compare the radiosensitization effect of mNP hyperthermia with that of microwave-induced hyperthermia. The effects of incubation of nanoparticles within tumors (to allow nanoparticles to be endocytosed) before application of AMF and radiation were determined. This preliminary information suggests cancer cell specific hyperthermia (i.e. antibody-directed or anatomically-directed mNP) is capable of providing significantly greater radiosensitization / therapeutic ratio enhancement than other forms of hyperthermia delivery.

  14. High-risk lesions diagnosed at MRI-guided vacuum-assisted breast biopsy: can underestimation be predicted?

    Energy Technology Data Exchange (ETDEWEB)

    Crystal, Pavel [Mount Sinai Hospital, University Health Network, Division of Breast Imaging, Toronto, ON (Canada); Mount Sinai Hospital, Toronto, ON (Canada); Sadaf, Arifa; Bukhanov, Karina; Helbich, Thomas H. [Mount Sinai Hospital, University Health Network, Division of Breast Imaging, Toronto, ON (Canada); McCready, David [Princess Margaret Hospital, Department of Surgical Oncology, Toronto, ON (Canada); O' Malley, Frances [Mount Sinai Hospital, Department of Pathology, Laboratory Medicine, Toronto, ON (Canada)

    2011-03-15

    To evaluate the frequency of diagnosis of high-risk lesions at MRI-guided vacuum-assisted breast biopsy (MRgVABB) and to determine whether underestimation may be predicted. Retrospective review of the medical records of 161 patients who underwent MRgVABB was performed. The underestimation rate was defined as an upgrade of a high-risk lesion at MRgVABB to malignancy at surgery. Clinical data, MRI features of the biopsied lesions, and histological diagnosis of cases with and those without underestimation were compared. Of 161 MRgVABB, histology revealed 31 (19%) high-risk lesions. Of 26 excised high-risk lesions, 13 (50%) were upgraded to malignancy. The underestimation rates of lobular neoplasia, atypical apocrine metaplasia, atypical ductal hyperplasia, and flat epithelial atypia were 50% (4/8), 100% (5/5), 50% (3/6) and 50% (1/2) respectively. There was no underestimation in the cases of benign papilloma without atypia (0/3), and radial scar (0/2). No statistically significant differences (p > 0.1) between the cases with and those without underestimation were seen in patient age, indications for breast MRI, size of lesion on MRI, morphological and kinetic features of biopsied lesions. Imaging and clinical features cannot be used reliably to predict underestimation at MRgVABB. All high-risk lesions diagnosed at MRgVABB require surgical excision. (orig.)

  15. A MR-conditional High-torque Pneumatic Stepper Motor for MRI-guided and Robot-assisted Intervention

    Science.gov (United States)

    Chen, Yue; Kwok, Ka-Wai; Tse, Zion Tsz Ho

    2015-01-01

    Magnetic Resonance Imaging allows for visualizing detailed pathological and morphological changes of soft tissue. This increasingly attracts attention on MRI-guided intervention; hence, MR-conditional actuations have been widely investigated for development of image-guided and robot-assisted surgical devices under the MRI. This paper presents a simple design of MR-conditional stepper motor which can provide precise and high-torque actuation without adversely affecting the MR image quality. This stepper motor consists of two MR-conditional pneumatic cylinders and the corresponding supporting structures. Alternating the pressurized air can drive the motor to rotate each step in 3.6° with the motor coupled to a planetary gearbox. Experimental studies were conducted to validate its dynamics performance. Maximum 800mNm output torque can be achieved. The motor accuracy independently varied by two factors: motor operating speed and step size, was also investigated. The motor was tested within a Siemens 3T MRI scanner. The image artifact and the signal-to-noise ratio (SNR) were evaluated in order to study its MRI compliancy. The results show that the presented pneumatic stepper motor generated 2.35% SNR reduction in MR images and no observable artifact was presented besides the motor body itself. The proposed motor test also demonstrates a standard to evaluate the motor capability for later incorporation with motorized devices used in robot-assisted surgery under MRI. PMID:24957635

  16. Interaction of hyperthermia and photoradiation therapy

    International Nuclear Information System (INIS)

    Waldow, S.M.; Dougherty, T.J.

    1984-01-01

    Local microwave hyperthermia (2450 MHz) was applied to auxillary implants of the SMT-F mammary carcinoma in mice in combination with photoradiation therapy (PRT) in an attempt to determine if the two modalities interact. When 40.5 0 C was applied for 30 min immediately prior to or immediately following PRT enhancement of tumor response over that of PRT alone was seen as judged by lack of tumor regrowth (35 days or longer after treatment). A temperature of 41.5 0 C applied for 30 min immediately following the 30-min PRT treatment produced a result slightly greater than that seen at 40.5 0 C. When a temperature of 44.5 0 C for 30 min was applied immediately following PRT, a substantial enhancement of tumor control at 35 days post-treatment was found. These results suggest that tumor response to PRT is enhanced by both a sublethal hyperthermic treatment (40.5 0 C, 41.5 0 C) and a moderately lethal heat treatment (44.5 0 C) given for a short duration, when applied immediately before or after photoradiation

  17. WE-G-BRB-08: TG-51 Calibration of First Commercial MRI-Guided IMRT System in the Presence of 0.35 Tesla Magnetic Field.

    Science.gov (United States)

    Goddu, S; Green, O Pechenaya; Mutic, S

    2012-06-01

    The first real-time-MRI-guided radiotherapy system has been installed in a clinic and it is being evaluated. Presence of magnetic field (MF) during radiation output calibration may have implications on ionization measurements and there is a possibility that standard calibration protocols may not be suitable for dose measurements for such devices. In this study, we evaluated whether a standard calibration protocol (AAPM- TG-51) is appropriate for absolute dose measurement in presence of MF. Treatment delivery of the ViewRay (VR) system is via three 15,000Ci Cobalt-60 heads positioned 120-degrees apart and all calibration measurements were done in the presence of 0.35T MF. Two ADCL- calibrated ionization-chambers (Exradin A12, A16) were used for TG-51 calibration. Chambers were positioned at 5-cm depth, (SSD=105cm: VR's isocenter), and the MLC leaves were shaped to a 10.5cm × 10.5 cm field size. Percent-depth-dose (PDD) measurements were performed for 5 and 10 cm depths. Individual output of each head was measured using the AAPM- TG51 protocol. Calibration accuracy for each head was subsequently verified by Radiological Physics Center (RPC) TLD measurements. Measured ion-recombination (Pion) and polarity (Ppol) correction factors were less-than 1.002 and 1.006, respectively. Measured PDDs agreed with BJR-25 within ±0.2%. Maximum dose rates for the reference field size at VR's isocenter for heads 1, 2 and 3 were 1.445±0.005, 1.446±0.107, 1.431±0.006 Gy/minute, respectively. Our calibrations agreed with RPC- TLD measurements within ±1.3%, ±2.6% and ±2.0% for treatment-heads 1, 2 and 3, respectively. At the time of calibration, mean activity of the Co-60 sources was 10,800Ci±0.1%. This study shows that the TG- 51 calibration is feasible in the presence of 0.35T MF and the measurement agreement is within the range of results obtainable for conventional treatment machines. Drs. Green, Goddu, and Mutic served as scientific consultants for ViewRay, Inc. Dr. Mutic

  18. The Positive Outcome of MRI-Guided Vacuum Assisted Core Needle Breast Biopsies Is Not Influenced by a Prior Negative Targeted Second-Look Ultrasound.

    Science.gov (United States)

    Ferré, Romuald; AlSharif, Shaza; Aldis, Ann; Mesurolle, Benoît

    2017-11-01

    The study sought to investigate the outcome of breast magnetic resonance-guided biopsies as a function of the indication for magnetic resonance imaging (MRI), the MRI features of the lesions, and the performance or not of a targeted second-look ultrasound (SLUS) prior breast MRI-guided biopsy. We identified 158 women with MRI-detected breast lesions scheduled for MRI-guided biopsy (2007-2013). Patient demographics, performance of targeted SLUS, imaging characteristics, and subsequent pathology results were reviewed. Three biopsies were deferred, and 155 lesions were biopsied under MRI guidance (155 women; median age 55.14 years; range 27-80 years). Ninety-eight women underwent a SLUS prior to the MRI-guided biopsy (63%). Of the 155 biopsied lesions, 23 (15%) were malignant, 106 (68%) were benign, and 26 (17%) were high risk. Four of 15 surgically excised high-risk lesions were upgraded to malignancy (27%). Most of the biopsied lesions corresponded to non-mass-like enhancement (81%, 126 of 155) and most of the biopsies (52%, 81 of 155) were performed in a screening context. No demographic or MRI features were associated with malignancy. No differences were noted between the 2 subgroups (prior SLUS vs no prior SLUS) except for the presence of a synchronous carcinoma associated with a likelihood of targeted SLUS before MRI-guided biopsy (P = .001). A negative SLUS does not influence the pathology outcome of a suspicious lesion biopsied under MR guidance. Copyright © 2017 Canadian Association of Radiologists. Published by Elsevier Inc. All rights reserved.

  19. Computational evaluation of amplitude modulation for enhanced magnetic nanoparticle hyperthermia.

    Science.gov (United States)

    Soetaert, Frederik; Dupré, Luc; Ivkov, Robert; Crevecoeur, Guillaume

    2015-10-01

    Magnetic nanoparticles (MNPs) can interact with alternating magnetic fields (AMFs) to deposit localized energy for hyperthermia treatment of cancer. Hyperthermia is useful in the context of multimodality treatments with radiation or chemotherapy to enhance disease control without increased toxicity. The unique attributes of heat deposition and transfer with MNPs have generated considerable attention and have been the focus of extensive investigations to elucidate mechanisms and optimize performance. Three-dimensional (3D) simulations are often conducted with the finite element method (FEM) using the Pennes' bioheat equation. In the current study, the Pennes' equation was modified to include a thermal damage-dependent perfusion profile to improve model predictions with respect to known physiological responses to tissue heating. A normal distribution of MNPs in a model liver tumor was combined with empirical nanoparticle heating data to calculate tumor temperature distributions and resulting survival fraction of cancer cells. In addition, calculated spatiotemporal temperature changes were compared among magnetic field amplitude modulations of a base 150-kHz sinusoidal waveform, specifically, no modulation, sinusoidal, rectangular, and triangular modulation. Complex relationships were observed between nanoparticle heating and cancer tissue damage when amplitude modulation and damage-related perfusion profiles were varied. These results are tantalizing and motivate further exploration of amplitude modulation as a means to enhance efficiency of and overcome technical challenges associated with magnetic nanoparticle hyperthermia (MNH).

  20. TH-CD-202-11: Implications for Online Adaptive and Non-Adaptive Radiotherapy of Gastic and Gastroesophageal Junction Cancers Using MRI-Guided Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Mittauer, K; Geurts, M; Toya, R; Bassetti, M; Harari, P; Paliwal, B; Bayouth, J [University of Wisconsin, Madison, WI (United States)

    2016-06-15

    Purpose: Radiotherapy for gastric and gastroesophageal junction (GEJ) tumors commonly requires large margins due to deformation, motion and variable changes of the stomach anatomy, at the risk of increased normal tissue toxicities. This work quantifies the interfraction variation of stomach deformation from daily MRI-guided radiotherapy to allow for a more targeted determination of margin expansion in the treatment of gastric and GEJ tumors. Methods: Five patients treated for gastric (n=3) and gastroesophageal junction (n=2) cancers with conventionally fractionated radiotherapy underwent daily MR imaging on a clinical MR-IGRT system. Treatment planning and contours were performed based on the MR simulation. The stomach was re-contoured on each daily volumetric setup MR. Dice similarity coefficients (DSC) of the daily stomach were computed to evaluate the stomach interfraction deformation. To evaluate the stomach margin, the maximum Hausdorff distance (HD) between the initial and fractional stomach surface was measured for each fraction. The margin expansion, needed to encompass all fractions, was evaluated from the union of all fractional stomachs. Results: In total, 94 fractions with daily stomach contours were evaluated. For the interfraction stomach differences, the average DSC was 0.67±0.1 for gastric and 0.62±0.1 for GEJ cases. The maximum HD of each fraction was 3.5±2.0cm (n=94) with mean HD of 0.8±0.4cm (across all surface voxels for all fractions). The margin expansion required to encompass all individual fractions (averaged across 5 patients) was 1.4 cm(superior), 2.3 cm(inferior), 2.5 cm(right), 3.2 cm(left), 3.7 cm(anterior), 3.4 cm(posterior). Maximum observed difference for margin expansion was 8.7cm(posterior) among one patient. Conclusion: We observed a notable interfractional change in daily stomach shape (i.e., mean DSC of 0.67, p<0.0001) in both gastric and GEJ patients, for which adaptive radiotherapy is indicated. A minimum PTV margin of 3

  1. TH-CD-202-11: Implications for Online Adaptive and Non-Adaptive Radiotherapy of Gastic and Gastroesophageal Junction Cancers Using MRI-Guided Radiotherapy

    International Nuclear Information System (INIS)

    Mittauer, K; Geurts, M; Toya, R; Bassetti, M; Harari, P; Paliwal, B; Bayouth, J

    2016-01-01

    Purpose: Radiotherapy for gastric and gastroesophageal junction (GEJ) tumors commonly requires large margins due to deformation, motion and variable changes of the stomach anatomy, at the risk of increased normal tissue toxicities. This work quantifies the interfraction variation of stomach deformation from daily MRI-guided radiotherapy to allow for a more targeted determination of margin expansion in the treatment of gastric and GEJ tumors. Methods: Five patients treated for gastric (n=3) and gastroesophageal junction (n=2) cancers with conventionally fractionated radiotherapy underwent daily MR imaging on a clinical MR-IGRT system. Treatment planning and contours were performed based on the MR simulation. The stomach was re-contoured on each daily volumetric setup MR. Dice similarity coefficients (DSC) of the daily stomach were computed to evaluate the stomach interfraction deformation. To evaluate the stomach margin, the maximum Hausdorff distance (HD) between the initial and fractional stomach surface was measured for each fraction. The margin expansion, needed to encompass all fractions, was evaluated from the union of all fractional stomachs. Results: In total, 94 fractions with daily stomach contours were evaluated. For the interfraction stomach differences, the average DSC was 0.67±0.1 for gastric and 0.62±0.1 for GEJ cases. The maximum HD of each fraction was 3.5±2.0cm (n=94) with mean HD of 0.8±0.4cm (across all surface voxels for all fractions). The margin expansion required to encompass all individual fractions (averaged across 5 patients) was 1.4 cm(superior), 2.3 cm(inferior), 2.5 cm(right), 3.2 cm(left), 3.7 cm(anterior), 3.4 cm(posterior). Maximum observed difference for margin expansion was 8.7cm(posterior) among one patient. Conclusion: We observed a notable interfractional change in daily stomach shape (i.e., mean DSC of 0.67, p<0.0001) in both gastric and GEJ patients, for which adaptive radiotherapy is indicated. A minimum PTV margin of 3

  2. Respiratory motion-resolved, self-gated 4D-MRI using Rotating Cartesian K-space (ROCK): Initial clinical experience on an MRI-guided radiotherapy system.

    Science.gov (United States)

    Han, Fei; Zhou, Ziwu; Du, Dongsu; Gao, Yu; Rashid, Shams; Cao, Minsong; Shaverdian, Narek; Hegde, John V; Steinberg, Michael; Lee, Percy; Raldow, Ann; Low, Daniel A; Sheng, Ke; Yang, Yingli; Hu, Peng

    2018-06-01

    To optimize and evaluate the respiratory motion-resolved, self-gated 4D-MRI using Rotating Cartesian K-space (ROCK-4D-MRI) method in a 0.35 T MRI-guided radiotherapy (MRgRT) system. The study included seven patients with abdominal tumors treated on the MRgRT system. ROCK-4D-MRI and 2D-CINE, was performed immediately after one of the treatment fractions. Motion quantification based on 4D-MRI was compared with those based on 2D-CINE. The image quality of 4D-MRI was evaluated against 4D-CT. The gross tumor volumes (GTV) were defined based on individual respiratory phases of both 4D-MRI and 4D-CT and compared for their variability over the respiratory cycle. The motion measurements based on 4D-MRI matched well with 2D-CINE, with differences of 1.04 ± 0.52 mm in the superior-inferior and 0.54 ± 0.21 mm in the anterior-posterior directions. The image quality scores of 4D-MRI were significantly higher than 4D-CT, with better tumor contrast (3.29 ± 0.76 vs. 1.86 ± 0.90) and less motion artifacts (3.57 ± 0.53 vs. 2.29 ± 0.95). The GTVs were more consistent in 4D-MRI than in 4D-CT, with significantly smaller GTV variability (9.31 ± 4.58% vs. 34.27 ± 23.33%). Our study demonstrated the clinical feasibility of using the ROCK-4D-MRI to acquire high quality, respiratory motion-resolved 4D-MRI in a low-field MRgRT system. The 4D-MRI image could provide accurate dynamic information for radiotherapy treatment planning. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. SU-F-J-145: MRI-Guided Interventional Boost Radiotherapy for Rectal Cancer: Investigating the Feasibility of Adapting the Anatomy

    Energy Technology Data Exchange (ETDEWEB)

    Kleijnen, J J E; Couwenberg, A M; Asselen, B van; Lagendijk, J J W; Intven, M; Raaymakers, B W [University Medical Center Utrecht, Utrecht, Utrecht (Netherlands)

    2016-06-15

    Purpose: The recent development of an MRI-linac allows adaptation of treatments to the anatomy of the moment. This anatomy, in turn, could be altered into a more favorable situation for radiotherapy purposes. The purpose of this study is to investigate the potential dosimetric benefits of manipulating rectal anatomy in MRI-guided interventional external-beam radiotherapy for rectal cancer. Methods: For this retrospective analysis, four patients (1M/3F) diagnosed with rectal cancer were included. These underwent MR-imaging using sonography transmission gel as endorectal contrast at time of diagnosis and standard, non-contrast, MR-imaging prior to radiotherapy planning. In the contrast scan, the rectum is inflated by the inserted contrast gel, thereby potentially increasing the distance between tumor and the organs-at-risk (OAR). Both anatomies were delineated and 7- beam IMRT-plans were calculated for both situations (RT-standard and RT-inflated), using in-house developed treatment planning software. Each plan was aimed to deliver 15Gy to the planning target volume (PTV; tumor+3mm margin) with a D99>95% and Dmax<120% of the planned dose. The D2cc dose to the OAR were then compared for both situations. Results: At equal (or better) target coverage, we found a mean reduction in D2cc of 4.1Gy/237% [range 2.6Gy–6.3Gy/70%–621%] for the bladder and of 2.0Gy/145% [range −0.7Gy–7.9Gy/−73%–442%] for the small-bowel, for the RT-inflated compared to the RT-standard plans. For the three female patients, a reduction in D2cc of 5.2Gy/191% [range 3.2Gy–9.2Gy/44%–475%] for the gynecological organs was found. We found all D2cc doses to be better for the RT-inflated plans, except for one patient for whom the bladder D2cc dose was slightly increased. Conclusion: Reduction of OAR dose by manipulation of anatomy is feasible. Inflation of the rectum results in more distance between OAR and PTV. This leads to a substantial reduction in dose to OAR at equal or better target

  4. Highly directional transurethral ultrasound applicators with rotational control for MRI-guided prostatic thermal therapy

    Energy Technology Data Exchange (ETDEWEB)

    Ross, Anthony B [Thermal Therapy Research Group, UCSF Radiation Oncology, San Francisco, CA (United States); Diederich, Chris J [Thermal Therapy Research Group, UCSF Radiation Oncology, San Francisco, CA (United States); Nau, William H [Thermal Therapy Research Group, UCSF Radiation Oncology, San Francisco, CA (United States); Gill, Harcharan [Department of Urology, Stanford University, Stanford, CA (United States); Bouley, Donna M [Department of Comparative Medicine, Stanford University, Stanford, CA (United States); Daniel, Bruce [Department of Radiology, Stanford University, Stanford, CA (United States); Rieke, Viola [Department of Radiology, Stanford University, Stanford, CA (United States); Butts, R Kim [Department of Radiology, Stanford University, Stanford, CA (United States); Sommer, Graham [Department of Radiology, Stanford University, Stanford, CA (United States)

    2004-01-21

    Transurethral ultrasound applicators with highly directional energy deposition and rotational control were investigated for precise treatment of benign prostatic hyperplasia (BPH) and adenocarcinoma of the prostate (CaP). Two types of catheter-based applicators were fabricated, using either sectored tubular (3.5 mm OD x 10 mm) or planar transducers (3.5 mm x 10 mm). They were constructed to be MRI compatible, minimally invasive and allow for manual rotation of the transducer array within a 10 mm cooling balloon. In vivo evaluations of the applicators were performed in canine prostates (n 3) using MRI guidance (0.5 T interventional magnet). MR temperature imaging (MRTI) utilizing the proton resonance frequency shift method was used to acquire multiple-slice temperature overlays in real time for monitoring and guiding the thermal treatments. Post-treatment T1-weighted contrast-enhanced imaging and triphenyl tetrazolium chloride stained tissue sections were used to define regions of tissue coagulation. Single sonications with the tubular applicator ) produced coagulated zones covering a wedge of the prostate extending from 1-2 mm outside the urethra to the outer boundary of the gland (16 mm radial coagulation). Single sonications with the planar applicator (15-20 W, 10 min, {approx}8 MHz) generated thermal lesions of {approx}30 extending to the prostate boundary. Multiple sequential sonications (sweeping) of a planar applicator (12 W with eight rotations of 30 each) demonstrated controllable coagulation of a 270 contiguous section of the prostate extending to the capsule boundary. The feasibility of using highly directional transurethral ultrasound applicators with rotational capabilities to selectively coagulate regions of the prostate while monitoring and controlling the treatments with MRTI was demonstrated in this study.

  5. Neo-adjuvant chemotherapy alone or with regional hyperthermia for localised high-risk soft-tissue sarcoma: a randomised phase 3 multicentre study

    DEFF Research Database (Denmark)

    Issels, Rolf D; Lindner, Lars H; Verweij, Jaap

    2010-01-01

    The optimum treatment for high-risk soft-tissue sarcoma (STS) in adults is unclear. Regional hyperthermia concentrates the action of chemotherapy within the heated tumour region. Phase 2 studies have shown that chemotherapy with regional hyperthermia improves local control compared with chemother...

  6. MRI-guided therapeutic ultrasound: Temperature feedback control for extracorporeal and endoluminal applicators

    Science.gov (United States)

    Salomir, Rares

    2005-09-01

    Therapeutic ultrasound is a mini-invasive and promising tool for in situ ablation of non-resectable tumors in uterus, breast, esophagus, kidney, liver, etc. Extracorporeal, endoluminal, and interstitial applicators have been successfully tested to date. Magnetic resonance imaging (MRI) is the only available technique providing non-invasive temperature mapping, together with excellent contrast of soft tissue. Coupling of these two technologies offers the advantage of both: (1) on line spatial guidance to the target region, and (2) thermal dose control during the treatment. This talk will provide an overview of the author's experience with automatic, active feedback control of the temperature evolution in tissues, which has been demonstrated with MRI compatible extracorporeal transducers (focused beam) or endoluminal applicators (plane waves). The feedback loop is based on fast switching capabilities of the driving electronics and real time data transfer out of the MR scanner. Precision of temperature control was typically better than 1°C. This approach is expected to improve the efficacy of the treatment (complete tumor ablation) and the thermal security of the critical regions crossed by the acoustic beam. It also permits one to reach an under-lethal heating regime for local drug delivery using thermosensitive liposomes or gene expression control based on hsp promoters.

  7. Thermometric analysis of intra-cavitary hyperthermia for esophageal cancer.

    Science.gov (United States)

    Qi, C; Li, D J

    1999-01-01

    Thermometric analysis was carried out in 51 patients with esophageal cancer treated with intra-cavitary hyperthermia combined with radio chemotherapy, to test whether temperature index (T20, T50) and T90) could be used as an indicator for tumour control. Hyperthermia was administered by intra-cavitary microwave applicator. The T20, T50 and T90 were deducted from the temperature sensors T0 and T3 situated at the center of the tumour surface and 3cm from it. Eighteen patients with local control > or =36 months were named long term control patients (LC), 24 patients with local recurrence within 24 months (LR) (there were no events occurring between 24 and 36 months) and nine patients died of metastasis without local recurrence (DM). The overall survival rates were 80.4 +/- 5.6% at 1 year, 38.3 +/- 6.9% at 3 years and 31 +/- 6.7% at 5 years, respectively. Chi-square test showed no influence of the number of hyperthermia sessions on the local control (p > 0.25). The 5-year local control rate was 18.8% for the patients with T90 or = 43 degrees C (p < 0.01). The average T90 was 43.76 +/- 0.74 degrees C for the LC patients and 43.17 +/- 0.57 degrees C for those LR (p = 0.024). The mean T90 was higher than 43 degrees C in 94.4% of LC, whereas in 58.8% of LR. The study suggested that T90 was a good parameter for thermal dose in the intracavitary hyperthermia for the treatment of esophageal cancer.

  8. Relationships between thermal dose parameters and the efficacy of definitive chemoradiotherapy plus regional hyperthermia in the treatment of locally advanced cervical cancer: data from a multicentre randomised clinical trial.

    Science.gov (United States)

    Ohguri, Takayuki; Harima, Yoko; Imada, Hajime; Sakurai, Hideyuki; Ohno, Tatsuya; Hiraki, Yoshiyuki; Tuji, Koh; Tanaka, Masahiro; Terashima, Hiromi

    2018-06-01

    To evaluate the contribution of the thermal dose parameters during regional hyperthermia (HT) treatment to the clinical outcomes in patients with cervical carcinoma (CC) who received chemoradiotherapy (CRT) plus HT. Data from a multicentre randomised clinical trial of concurrent CRT + HT vs. CRT alone were used to evaluate the efficacy and safety of this combination therapy in the CC patients. The intrarectal temperatures of patients undergoing HT were recorded. The complete thermal data of 47 (92%) of the 51 patients in the CRT + HT group were available for the thermal analysis. Thus, 47 patients who received CRT + HT were included in the present study. Among the patients who received CRT + HT, a higher CEM43T90 (≥1 min) value (a thermal dose parameter) was significantly associated with better local relapse-free survival in both univariate (p = 0.024) and multivariate (p = 0.0097) analyses. The disease-free survival of the patients with higher CEM43T90 (≥1 min) values tended to be better in comparison to patients with lower CEM43T90 (<1 min) value (p = 0.071). A complete response tended to be associated with the CEM43T90 (p = 0.056). Disease-free survival, local relapse-free survival and complete response rate for patients with higher CEM43T90 (≥1) were significantly better than those for patients with CRT alone (p = 0.036, p = 0.036 and p = 0.048). Dose-effect relationships between thermal dose parameters and clinical outcomes were confirmed in the CC patients treated with a combination of CRT + HT. This study also confirmed that HT with lower CEM43T90 is insufficient to achieve a significant hyperthermic sensitisation to CRT.

  9. SU-F-J-17: Patient Localization Using MRI-Guided Soft Tissue for Head-And-Neck Radiotherapy: Indication for Margin Reduction and Its Feasibility

    International Nuclear Information System (INIS)

    Qi, X; Yang, Y; Jack, N; Santhanam, A; Yang, L; Chen, A; Low, D

    2016-01-01

    Purpose: On-board MRI provides superior soft-tissue contrast, allowing patient alignment using tumor or nearby critical structures. This study aims to study H&N MRI-guided IGRT to analyze inter-fraction patient setup variations using soft-tissue targets and design appropriate CTV-to-PTV margin and clinical implication. Methods: 282 MR images for 10 H&N IMRT patients treated on a ViewRay system were retrospectively analyzed. Patients were immobilized using a thermoplastic mask on a customized headrest fitted in a radiofrequency coil and positioned to soft-tissue targets. The inter-fraction patient displacements were recorded to compute the PTV margins using the recipe: 2.5∑+0.7σ. New IMRT plans optimized on the revised PTVs were generated to evaluate the delivered dose distributions. An in-house dose deformation registration tool was used to assess the resulting dosimetric consequences when margin adaption is performed based on weekly MR images. The cumulative doses were compared to the reduced margin plans for targets and critical structures. Results: The inter-fraction displacements (and standard deviations), ∑ and σ were tabulated for MRI and compared to kVCBCT. The computed CTV-to-PTV margin was 3.5mm for soft-tissue based registration. There were minimal differences between the planned and delivered doses when comparing clinical and the PTV reduced margin plans: the paired t-tests yielded p=0.38 and 0.66 between the planned and delivered doses for the adapted margin plans for the maximum cord and mean parotid dose, respectively. Target V95 received comparable doses as planned for the reduced margin plans. Conclusion: The 0.35T MRI offers acceptable soft-tissue contrast and good spatial resolution for patient alignment and target visualization. Better tumor conspicuity from MRI allows soft-tissue based alignments with potentially improved accuracy, suggesting a benefit of margin reduction for H&N radiotherapy. The reduced margin plans (i.e., 2 mm) resulted

  10. MO-B-201-03: MRI-Guided Tracking and Gating

    Energy Technology Data Exchange (ETDEWEB)

    Green, O. [Washington University School of Medicine (United States)

    2016-06-15

    The motion management in stereotactic body radiation therapy (SBRT) is a key to success for a SBRT program, and still an on-going challenging task. A major factor is that moving structures behave differently than standing structures when examined by imaging modalities, and thus require special considerations and employments. Understanding the motion effects to these different imaging processes is a prerequisite for a decent motion management program. The commonly used motion control techniques to physically restrict tumor motion, if adopted correctly, effectively increase the conformity and accuracy of hypofractionated treatment. The effective application of such requires one to understand the mechanics of the application and the related physiology especially related to respiration. The image-guided radiation beam control, or tumor tracking, further realized the endeavor for precision-targeting. During tumor tracking, the respiratory motion is often constantly monitored by non-ionizing beam sources using the body surface as its surrogate. This then has to synchronize with the actual internal tumor motion. The latter is often accomplished by stereo X-ray imaging or similar techniques. With these advanced technologies, one may drastically reduce the treated volume and increase the clinicians’ confidence for a high fractional ablative radiation dose. However, the challenges in implementing the motion management may not be trivial and is dependent on each clinic case. This session of presentations is intended to provide an overview of the current techniques used in managing the tumor motion in SBRT, specifically for routine lung SBRT, proton based treatments, and newly-developed MR guided RT. Learning Objectives: Through this presentation, the audience will understand basic roles of commonly used imaging modalities for lung cancer studies; familiarize the major advantages and limitations of each discussed motion control methods; familiarize the major advantages and

  11. MO-FG-BRA-07: Theranostic Gadolinium-Based AGuIX Nanoparticles for MRI-Guided Radiation Therapy

    International Nuclear Information System (INIS)

    Detappe, A; Rottmann, J; Kunjachan, S; Berbeco, R; Tillement, O

    2015-01-01

    Purpose: AGuIX are gadolinium-based nanoparticles, initially developed for MRI, that have a potential role in radiation therapy as a radiosensitizer. Our goal is to demonstrate that these nanoparticles can both be used as an MRI contrast agent, as well as to obtain local dose enhancement in a pancreatic tumor when delivered in combination with an external beam irradiation. Methods: We performed in vitro cell uptake and radiosensitization studies of a pancreatic cancer cell line in a low energy (220kVp) beam, a standard clinical 6MV beam (STD) and a flattening filter free clinical 6MV beam (FFF). After injection of 40mM of nanoparticles, a biodistribution study was performed in vivo on mice with subcutaneous xenograft pancreatic tumors. In vivo radiation therapy studies were performed at the time point of maximum tumor uptake. Results: The concentration of AGuIX nanoparticles in Panc-1 pancreatic cancer cells, determined in vitro by MRI and ICPMS, peaks after 30 minutes with 0.3% of the initial concentration (5mg/g). Clonogenic assays show a significant effect (p<0.05) when the AGuIX are coupled with MV photon irradiation (DEF20%=1.31). Similar AGuIX tumor uptake is found in vivo by both MRI and ICPMS 30 minutes after intravenous injection. For long term survival studies, the choice of the radiation dose is determined with 5 control groups (3mice/group) irradiated with 0, 5, 10, 15, and 20Gy. Afterwards, 4 groups (8mice/group) are used to evaluate the effect of the nanoparticles. A Logrank test is performed as a statistical test to evaluate the effect of the nanoparticles. Conclusion: The combination of the MRI contrast and radiosensitization properties of gadolinium nanoparticles reveals a strong potential for usage with MRI-guided radiation therapy

  12. Clinical investigation of the safety and efficacy of a cervical intraepithelial neoplasia treatment using a hyperthermia device that uses heat induced by alternating magnetic fields

    Science.gov (United States)

    Koizumi, Koji; Fujioka, Toru; Yasuoka, Toshiaki; Inoue, Aya; Uchikura, Yuka; Tanaka, Hiroki; Takagi, Katsuko; Mori, Miki; Koizumi, Masae; Hashimoto, Hisashi; Matsumoto, Takashi; Matsubara, Yuko; Matsubara, Keiichi; Nawa, Akihiro

    2016-01-01

    Multiple techniques have been used for the conservative treatment of high-grade cervical intraepithelial neoplasia (HG-CIN) in women of fertile age. Conization has been associated with stenosis of the cervix and a decrease in cervical mucus secretion, in addition to the increase in the risk of cervical canal shortening and problems during the perinatal period, including premature birth and premature rupture of membranes. Although the laser transpiration technique does not cause shortening of the cervical canal, it is associated with the recurrent risk of deep residual disease. The present study aimed to investigate the therapeutic safety and efficacy of the therapy performed using the transaction magnetic field induction heating device, AMTC400, in fertile patients with HG-CIN (excluding carcinoma in situ). Four premenopausal patients with CIN3 and high-risk human papilloma virus (HPV)-positive were treated using an AMTC400. Chronological colposcopic findings, high-risk HPV, final histological findings with conization and follow-up data were evaluated. All the treatments were successfully performed on the in-patients without anesthesia. Intra- and postoperative complications included minor pain and bleeding in all cases. Two of the cases (50%) were high-risk HPV-negative following the treatments. All cases exhibited a change in the observed color (to white), and subsequent epithelization following treatment. Although cytological analysis at 5 weeks following the treatment confirmed the cases were negative for intraepithelial lesions and malignancies, a definitive histology with conization 6 weeks following the treatment confirmed CIN1 and koilocytosis in all cases. The assessment of treatment effectiveness was determined as a moderate improvement in all cases. In conclusion, thermotherapy applied using AMTC400 represented a safe and effective treatment for HG-CIN in women of fertile age. However, additional improvements associated with the site of puncture needles

  13. MRI-Guided Diffuse Optical Spectroscopy of Malignant and Benign Breast Lesions

    Directory of Open Access Journals (Sweden)

    Vasilis Ntziachristos

    2002-01-01

    Full Text Available We present the clinical implementation of a novel hybrid system that combines magnetic resonance imaging (MRI and near-infrared (NIR optical measurements for the noninvasive study of breast cancer in vivo. Fourteen patients were studied with a MR-NIR prototype imager and spectrometer. A diffuse optical tomographic scheme employed the MR images as a priori information to implement an image-guided NIR localized spectroscopic scheme. All patients who entered the study also underwent gadolinium-enhanced MRI and biopsy so that the optical findings were crossvalidated with MR readings and histopathology. The technique quantified the oxy-and deoxyhemoglobin of five malignant and nine benign breast lesions in vivo. Breast cancers were found with decreased oxygen saturation and higher blood concentration than most benign lesions. The average hemoglobin concentration ([H] of cancers was 0.130±0.100 mM, and the average hemoglobin saturation (Y was 60±9% compared to [H]=0.018±0.005 mM and Y=69±6% of background tissue. Fibroadenomas exhibited high hemoglobin concentration [H]=0.060±0.010 mM and mild decrease in oxygen saturation Y=67±2%. Cysts and other normal lesions were easily differentiated based on intrinsic contrast information. This novel optical technology can be a significant add-on in MR examinations and can be used to characterize functional parameters of cancers with diagnostic and treatment prognosis potential. It is foreseen that the technique can play a major role in functional activation studies of brain and muscle as well.

  14. MRI-guided gas bubble enhanced ultrasound heating in in vivo rabbit thigh

    International Nuclear Information System (INIS)

    Sokka, S D; King, R; Hynynen, K

    2003-01-01

    In this study, we propose a focused ultrasound surgery protocol that induces and then uses gas bubbles at the focus to enhance the ultrasound absorption and ultimately create larger lesions in vivo. MRI and ultrasound visualization and monitoring methods for this heating method are also investigated. Larger lesions created with a carefully monitored single ultrasound exposure could greatly improve the speed of tumour coagulation with focused ultrasound. All experiments were performed under MRI (clinical, 1.5 T) guidance with one of two eight-sector, spherically curved piezoelectric transducers. The transducer, either a 1.1 or 1.7 MHz array, was driven by a multi-channel RF driving system. The transducer was mounted in an MRI-compatible manual positioning system and the rabbit was situated on top of the system. An ultrasound detector ring was fixed with the therapy transducer to monitor gas bubble activity during treatment. Focused ultrasound surgery exposures were delivered to the thighs of seven New Zealand white rabbits. The experimental, gas-bubble-enhanced heating exposures consisted of a high amplitude 300 acoustic watt, half second pulse followed by a 7 W, 14 W or 21 W continuous wave exposure for 19.5 s. The respective control sonications were 20 s exposures of 14 W, 21 W and 28 W. During the exposures, MR thermometry was obtained from the temperature dependency of the proton resonance frequency shift. MR T2-enhanced imaging was used to evaluate the resulting lesions. Specific metrics were used to evaluate the differences between the gas-bubble-enhanced exposures and their respective control sonications: temperatures with respect to time and space, lesion size and shape, and their agreement with thermal dose predictions. The bubble-enhanced exposures showed a faster temperature rise within the first 4 s and higher overall temperatures than the sonications without bubble formation. The spatial temperature maps and the thermal dose maps derived from the MRI

  15. Clinical utility of an endorectal MRI-guided prostate probe: preliminary examinations

    Directory of Open Access Journals (Sweden)

    Tödter Julia

    2017-09-01

    Full Text Available Prostate cancer (PCa is one of the most common cancer diseases in men in the western countries [1]. Besides the palpation, and the amount of prostate-specific-antigen’s (PSA inside the blood, the current diagnostic imaging technologies are not appropriate. Early diagnosis defining the exact tumor location, spread and margins could make efficient targeted biopsies and image-guided surgery. A multimodal imaging technique containing a transmit-receive surface coil for anatomical MR imaging, a (SPET detector module, consisting of silicon photomultipliers (SiPM, for functional imaging and an ultrasound (US probe are placed as close as possible to the prostate designed as an endorectal tube to increase sensitivity and spatial resolution. All materials that are used are non-magnetic. Advantages of the SiPM are diversified, like non-sensitive to magnetic fields, higher gain (105–106 than standard avalanche photodiodes (APD, good timing properties and compactness. The PET detector should reach approximately 1mm3 spatial resolution together with 60ps FWHM Time-of-Flight resolution and a high efficiency to reduce scanning time and injected dose. A home-made transmit-receive coil surrounding the PET module improves signal-to-noise-ratio (SNR with respect to standard coils will be present. The system will be used as a MRI-insert and be able to visualize anatomic and metabolic information together. The US-probe is guiding examination for correct overlapping of the multimodal images. This procedure will save time, costs and the need of co-registration. By combining all advantages of each system, it will necessarily update the non-invasive treatment of PCa. The system is adapted and tested to a 3 Tesla MR scanner called Trio A Tim system and Allegra system from the company Siemens healthcare with a larmor frequency of 123.2 MHz and an input of 50 Ω free from artifacts. First results on homogeneity of the transmit-receive coil will be presented. Preliminary

  16. Effect of hyperthermia on radiation damage and its repair in Tribolium confusum

    International Nuclear Information System (INIS)

    Lai, P.K.

    1977-01-01

    A series of temperature tolerance curves from 43.5 0 C to 46.0 0 C in 0.5 0 C increment were determined. Two non-lethal hyperthermia schemes, i.e., 45.0 0 C for 2 hr and 43.0 0 C for 2 hr were chosen to examine the sensitizing effect of heat on lethality produced by radiation in flour beetles. When hyperthermia was applied either immediately before or after irradiation, the sensitizing effect of hyperthermia was indicated by the shifting of the regression line of survival in probits on dose to the left of that of the control. The sensitizing effect as measured by decreased LD 50 did not reveal any definite trend related to the order of application of the two modalities in immediate sequence. The effect of hyperthermia was more dramatic in dose-fractionation experiments. Flour beetles exhibited typical Elkind kinetics of split-dose repair and recovery, and the amount of the sparing effect of dose-fractionation (sdf) was influenced by interfraction temperature. Both interfraction hypothermia (i.e., less than or equal to 10 0 C) and interfraction hyperthermia (i.e., > 42.0 0 C) completely suppress sdf. However, the mechanism involved in the suppression of sdf by hypothermia was different than that by hyperthermia. In the former, the suppression of sdf was reversible immediately upon return to the normal incubation temperature of 30 0 C; in the latter, the suppression of sdf was protracted and the reversibility of sdf depended on the severity of the hyperthermia treatment. Hyperthermia of 43.0 0 C for 2 hr, applied either immediately before or after the first radiation dose, suppressed sdf for 6-10 hr, and then sdf reappeared slowly, so that the final level of survival was slightly less than that of the comparable groups maintained at 30 0 C. With the more severe hyperthermia treatment of 45.0 0 C for 2 hr, sdf was suppressed for almost 36 hr after return to 30 0 C although there were some slight surges in survival

  17. Intestinal cell proliferation following hyperthermia-radiation combinations

    International Nuclear Information System (INIS)

    Burholt, D.R.; Wilkinson, D.A.; Shrivastava, P.N.

    1987-01-01

    The present work is an investigation of the extent to which hyperthermia enhances x-ray induced inhibition of intestinal epithelial cell proliferation in mice. Hyperthermia was achieved by whole body immersion of anesthetized ice in a temperature controlled water bath (+-0.1 0 C). Post-treatment proliferative activity was monitored by determining the incorporation of /sup 3/H-TdR into intestinal crypt cells and by the counting of epithelial cell mitotic figures. Initial levels of cell kill were assessed by the microcolony crypt survival technique. All heat treatments were 41.5 0 C for 0.5h. Heat alone reduced the /sup 3/H-TdR incorporation to 50% of the control value by 2h post-treatment. This was followed by a return to control value by 10h and a slight hyperplasia at 24h. Heat either immediately before or after 2Gy abdominal field x-irradiation produced a prolonged period of depressed cell proliferation: /sup 3/H-TdR incorporation remained below control value for the first 24h. As the heat and radiation were separated in time from each other (up to 4h) the interaction between the two decreased. The development of thermotolerance was observed following the second and third treatment during either a heat-only or a heat-radiation multifraction treatments schedule with the treatment spaced 24h apart

  18. Hyperthermia-induced alteration of yeast susceptibility to mutation

    International Nuclear Information System (INIS)

    Mitchel, R.E.J.; Morrison, D.P.

    1985-01-01

    Diploid yeast (s. cerevisiae) were examined for alterations in susceptibility to induced mutation following hyperthermia treatment. In cells grown at 23 0 C, a non-lethal heat exposure (38 0 C, 30 min) markedly suppressed mutation induced by a subsequent non-killing dose of MNNG of MNU. Mutation by ENU, 8-MOP + UVA, or γ-rays was not affected. An intermediate level of mutation suppression was observed for mutation by 254nm UV or MMS. Mutation by MNNG was not suppressed by the same heat treatment delivered after the mutagen exposure. In a split dose experiment (two MNNG treatments separated by a heat exposure) no suppression of mutation was observed. Treatment with cycloheximide mimicked the effect of heat treatment. These data suggest that mutation induction by MNNG or MNU is protein synthesis dependent, i.e. an error-prone repair system is induced by exposure to MNNG or MNU but not by ENU, 8-MOP+UVA or γ-irradiation. We propose that hyperthermia treatment, by inducing stress protein synthesis at the expense of normal protein synthesis, precludes induction of this error-prone system. Therefore, in heat treated cells, DNA lesions produced by MNNG or MNU exposure must be resolved by an essentially constitutive system which is less error-prone than the inducible one

  19. Effect of hypothermia on cell kinetics and response to hyperthermia and x rays

    International Nuclear Information System (INIS)

    van Rijn, J.; van den Berg, J.; Kipp, J.B.A.; Schamhart, D.H.J.; van Wijk, R.

    1985-01-01

    Hyperthermia is a potent radio enhancer. Studies using hypothermia in combination with irradiation have given confusing results due to lack of uniformity in experimental design. This report shows that hypothermia might have potential significance in the treatment of malignant cells with both thermo- and radiotherapy. Reuber H35 hepatoma cells, clone KRC-7 were used to study the effect of hypothermia on cell kinetics and subsequent response to hyperthermia and/or X rays. Cells were incubated at 8.5 0 C or between 25 and 37 0 C for 24 hr prior to hyperthermia or irradiation. Hypothermia caused sensitization to both hyperthermia and X rays. In contrast to the effect of hypothermia on either hyperthermia or X rays alone, thermal radiosensitization was decreased in hypothermically pretreated cells (24 hr at 25 0 C) compared to control cells (37 0 C). The expression of thermotolerance and the rate of development at 37 0 C after an initial heating at 42.5 0 C were not influenced after preincubation at 25 0 C for 24 hr. The expression of thermotolerance for heat or heat plus X rays during incubation at 41 0 C occurred in a significantly smaller number of cells after 24 hr preincubation at 25 0 C. The enhanced thermo- and radiosensitivity in hypothermically treated cells disappeared in approximately 6 hr after return to 37 0 C

  20. Hyperfractionated radiation in combination with local hyperthermia in the treatment of advanced squamous cell carcinoma of the head and neck: a phase I-II study

    International Nuclear Information System (INIS)

    Amichetti, Maurizio; Romano, Mario; Busana, Lucia; Bolner, Andrea; Fellin, Gianni; Pani, Giuseppe; Tomio, Luigi; Valdagni, Riccardo

    1997-01-01

    Twenty-seven patients with cervical metastases from squamous cell head and neck tumours were treated with hyperfractionated XRT (total dose 69.60-76.80 Gy, 1.2 Gy b.i.d. five times a week) combined with a total of two to six sessions of superficial external HT. Acute local toxicity was mild; as major acute side effects, only one ulceration was recorded. No severe late side effects were observed. Late toxicity was similar to that observed in our previous studies with the combination of heat and radiation. Nodal complete response was observed in 77% of patients, partial response was observed in 15% of patients and no change was observed in 8% of patients. Five-year actuarial nodal control was 64.5 ± 19% and 5-year actuarial survival was 24 ± 10%. The treatment of nodal metastases from head and neck tumours with the combination of HT and hyperfractionated XRT is feasible with an acceptable acute and late toxicity profile

  1. An ultrasonic phased array applicator for deep localized hyperthermia

    International Nuclear Information System (INIS)

    Ocheltree, K.B.; Benkeser, P.J.; Foster, S.G.; Frizzell, L.A.; Cain, C.A.

    1984-01-01

    The use of an ultrasonic phased array applicator presents a major advantage over the fixed beam ultrasonic applicators which are typically used for clinical hyperthermia. Such an applicator allows focal region placement in the three dimensional treatment field by electronic steering instead of mechanical movement of the transducer assembly. The design of an array is discussed theoretically, considering that the constraints on grating lobes and power output for hyperthermic applications are quite different from those for imaging. The effects of various design parameters are discussed. Experimental results are presented for several arrays for frequencies under 1 Mhz

  2. Effects of hyperthermia on repair of radiation-induced DNA strand breaks

    International Nuclear Information System (INIS)

    Mills, M.D.; Meyn, R.E.

    1981-01-01

    Previous reports have suggested a relationship between the heat-induced changes in nucleoprotein and the hyperthermic enhancement of radiation sensitivity. In an effort to further understand these relationships, we measured the level of initial DNA strand break damage and the DNA strand break rejoining kinetics in Chinese hamster ovary cells following combined hyperthermia and ionizing radiation treatments. The amount of protein associated with DNA measured as the ratio of [ 3 H)leucine to [ 14 C]thymidine was also compared in chromatin isolated from both heated and unheated cells. The results of these experiments show that the initial level of radiation-induced DNA strand breaks is significantly enhanced by a prior hyperthermia treatment of 43 0 C for 30 min. Treatments at higher temperatures and longer treatments at the same temperature magnified this effect. Hyperthermia was also shown to cause a substantial inhibition of the DNA strand break rejoining after irradiation. Both the initial level of DNA damage and the rejoining kinetics recovered to normal levels with incubation at 37 0 C between the hyperthermia and radiation treatments. Recovery of these parameters coincided with the return of the amount of protein associated with DNA to normal values, further suggesting a relationship between the changes in nucleoprotein and the hyperthermic enhancement of radiation sensivivity

  3. Methamphetamine-induced hyperthermia and dopaminergic neurotoxicity in mice: pharmacological profile of protective and nonprotective agents.

    Science.gov (United States)

    Albers, D S; Sonsalla, P K

    1995-12-01

    Neurotoxic doses of methamphetamine (METH) can cause hyperthermia in experimental animals. Damage sustained to dopaminergic nerve terminals by this stimulant can be reduced by environmental cooling or by pharmacological manipulation which attenuates the hyperthermia. Many pharmacological agents with very diverse actions protect against METH-induced neuropathology. Several of these compounds, as well as drugs which do not protect, were investigated to determine if there was a relationship between protection and METH-induced hyperthermia. Mice received METH with or without concurrent administration of other drugs and core (i.e., colonic) temperature was monitored during treatment. The animals were sacrificed > or = 5 days later and neostriatal tyrosine hydroxylase activity and dopamine were measured. Core temperature was significantly elevated (> or = 2 degrees C) in mice treated with doses of METH which produced > or = 90% losses in striatal dopamine but not in mice less severally affected (only 50% loss of dopamine). Concurrent treatment of mice with METH and pharmacological agents which protected partially or completely from METH-induced toxicity also prevented the hyperthermic response (i.e., dopamine receptor antagonists, fenfluramine, dizocilpine, alpha-methyl-p-tyrosine, phenytoin, aminooxyacetic acid and propranol). These findings are consistent with the hypothesis that the hyperthermia produced by METH contributes to its neuropathology. However, studies with reserpine, a compound which dramatically lowers core temperature, demonstrated that hyperthermia per se is not a requirement for METH-induced neurotoxicity. Although core temperature was elevated in reserpinized mice treated with METH as compared with reserpinized control mice, their temperatures remained significantly lower than in nonreserpinized control mice. However, the hypothermic state produced in the reserpinized mice did not provide protection from METH-induced toxicity. These data demonstrate

  4. Stereotactic technique of RF antenna implantation for brain hyperthermia

    International Nuclear Information System (INIS)

    Takahashi, H.; Uzuka, T.; Grinev, I.; Tanaka, R.

    2005-01-01

    Full text: We have tried 13.56 MHz RF interstitial hyperthermia for the patients with malignant brain tumor. The purpose of this report is to assess the complication risk rate and the achievement yield of stereotactic procedure for RF antenna implantation into the deep-seated brain tumor. One hundred and twenty-five patients underwent 144 stereotactic RF antenna implantation procedures for interstitial hyperthermia for malignant brain tumors at Niigata University, Japan. One hundred and eight patients had malignant gliomas (54 primary, 54 recurrent), 24 had metastatic tumors, 5 had malignant lymphomas, 5 had meningiomas and 2 had miscellaneous tumors. Indication of this trial was the tumor with inoperative deep-seated tumor or elderly patients. RF antennas and catheters for thermistor probes were set into the tumor with stereotactic apparatus under local anesthesia. Postoperative CT scan underwent in order to assess the accuracy of antenna setting and to check the complications. The hyperthermic treatment underwent with a single antenna in 85 patients, 2 antennas in 43 patients, 3 in 2, 4 in 12, 5 in 1 and 6 antennas in 1 patient. Appropriate RF antenna positioning was obtained in 138 of 144 procedures (95.8 %). Six patients incurred complications (4.2 %). Three patients suffered intratumoral hemorrhage. RF antennas were set into the inappropriate position in 2 cases, hyperthermia was not achieved. One patient occurred with liquorrhea. However, six patients (4.2 %) incurred complications, stereotactic RF antenna setting was a safe and reliable technique of the hyperthermic treatment for the patients with malignant brain tumors. (author)

  5. Description and characterization of the novel hyperthermia- and thermoablation-system MFHregistered300F for clinical magnetic fluid hyperthermia

    International Nuclear Information System (INIS)

    Gneveckow, Uwe; Jordan, Andreas; Scholz, Regina; Bruess, Volker; Waldoefner, Norbert; Ricke, Jens; Feussner, Annelie; Hildebrandt, Bert; Rau, Beate; Wust, Peter

    2004-01-01

    Magnetic fluid hyperthermia (MFH) is a new approach to deposit heat power in deep tissues by overcoming limitations of conventional heat treatments. After infiltration of the target tissue with nanosized magnetic particles, the power of an alternating magnetic field is transformed into heat. The combination of the 100 kHz magnetic field applicator MFH registered 300F and the magnetofluid (MF), which both are designed for medical use, is investigated with respect to its dosage recommendations and clinical applicability. We found a magnetic field strength of up to 18 kA/m in a cylindrical treatment area of 20 cm diameter and aperture height up to 300 mm. The specific absorption rate (SAR) can be controlled directly by the magnetic field strength during the treatment. The relationship between magnetic field strength and the iron normalized SAR (SAR Fe ) is only slightly depending on the concentration of the MF and can be used for planning the target SAR. The achievable energy absorption rates of the MF distributed in the tissue is sufficient for either hyperthermia or thermoablation. The fluid has a visible contrast in therapeutic concentrations on a CT scanner and can be detected down to 0.01 g/l Fe in the MRI. The system has proved its capability and practicability for heat treatment in deep regions of the human body

  6. Intra-operative hyperthermia in a young Angus bull with a fatal outcome

    OpenAIRE

    Skelding, Alicia; Valverde, Alexander

    2017-01-01

    A healthy, 9-month-old black Angus bull was presented for elective penile-preputial translocation and caudal epididymectomy. After premedication and induction, general anesthesia was maintained with inhalant anesthetic. Over an hour into the anesthetic period the bull developed severe hyperthermia and hypercapnia that resulted in fatality despite treatment efforts.

  7. Intra-operative hyperthermia in a young Angus bull with a fatal outcome.

    Science.gov (United States)

    Skelding, Alicia; Valverde, Alexander

    2017-06-01

    A healthy, 9-month-old black Angus bull was presented for elective penile-preputial translocation and caudal epididymectomy. After premedication and induction, general anesthesia was maintained with inhalant anesthetic. Over an hour into the anesthetic period the bull developed severe hyperthermia and hypercapnia that resulted in fatality despite treatment efforts.

  8. Safety and tolerability of MRI-guided infusion of AAV2-hAADC into the mid-brain of nonhuman primate

    Directory of Open Access Journals (Sweden)

    Waldy San Sebastian

    2014-01-01

    Full Text Available Aromatic L-amino acid decarboxylase (AADC deficiency is a rare, autosomal-recessive neurological disorder caused by mutations in the DDC gene that leads to an inability to synthesize catecholamines and serotonin. As a result, patients suffer compromised development, particularly in motor function. A recent gene replacement clinical trial explored putaminal delivery of recombinant adeno-associated virus serotype 2 vector encoding human AADC (AAV2-hAADC in AADC-deficient children. Unfortunately, patients presented only modest amelioration of motor symptoms, which authors acknowledged could be due to insufficient transduction of putamen. We hypothesize that, with the development of a highly accurate MRI-guided cannula placement technology, a more effective approach might be to target the affected mid-brain neurons directly. Transduction of AADC-deficient dopaminergic neurons in the substantia nigra and ventral tegmental area with locally infused AAV2-hAADC would be expected to lead to restoration of normal dopamine levels in affected children. The objective of this study was to assess the long-term safety and tolerability of bilateral AAV2-hAADC MRI-guided pressurized infusion into the mid-brain of nonhuman primates. Animals received either vehicle, low or high AAV2-hAADC vector dose and were euthanized 1, 3, or 9 months after surgery. Our data indicate that effective mid-brain transduction was achieved without untoward effects.

  9. 31P-MRS study for the assessment of tumor response after radiotherapy and/or hyperthermia

    International Nuclear Information System (INIS)

    Kimura, Hirohiko; Itho, Satoshi; Nakatsugawa, Sigekazu; Maeda, Masayuki; Iwasaki, Toshiko; Yamamoto, Kazutaka; Ishii, Yasushi

    1992-01-01

    The metabolic changes of human lung cancer implanted in nude mice were studied by the use of in vivo 31 P nuclear magnetic resonance spectroscopy ( 31 P-MRS) after radiotherapy, hyperthermia or the combined therapy of radiation and hyperthermia. 31 P-MRS of the tumors showed increased Pi/β-NTP ratio and acidic pH value on 1 day after hyperthermia, that indicated metabolic decline caused by hyperthermia. On the other hand, lower Pi/β-NTP ratios during 3 to 10 days after irradiation suggested metabolic activation of the tumors. In the tumors treated with the combined therapy, 31 P-MRS revealed increase of Pi/β-NTP ratio within 1 day and its decrease subsequent 6 to 10 days after treatment, that indicated additive bi-phasic changes induced by radiation and hyperthermia, respectively. Since Pi/β-NTP ratio had significant correlation to the tumor blood perfusion measured by hydrogen gas clearance studies, these bi-phasic changes were considered to correspond to two different physiological states, namely, ischemic and reperfused states. 31 P-MRS obtained from tumors could be useful to asses the physiological consequence following radiation, hyperthermia or the combined therapy. (author)

  10. Intracranial inertial cavitation threshold and thermal ablation lesion creation using MRI-guided 220-kHz focused ultrasound surgery: preclinical investigation.

    Science.gov (United States)

    Xu, Zhiyuan; Carlson, Carissa; Snell, John; Eames, Matt; Hananel, Arik; Lopes, M Beatriz; Raghavan, Prashant; Lee, Cheng-Chia; Yen, Chun-Po; Schlesinger, David; Kassell, Neal F; Aubry, Jean-Francois; Sheehan, Jason

    2015-01-01

    In biological tissues, it is known that the creation of gas bubbles (cavitation) during ultrasound exposure is more likely to occur at lower rather than higher frequencies. Upon collapsing, such bubbles can induce hemorrhage. Thus, acoustic inertial cavitation secondary to a 220-kHz MRI-guided focused ultrasound (MRgFUS) surgery is a serious safety issue, and animal studies are mandatory for laying the groundwork for the use of low-frequency systems in future clinical trials. The authors investigate here the in vivo potential thresholds of MRgFUS-induced inertial cavitation and MRgFUS-induced thermal coagulation using MRI, acoustic spectroscopy, and histology. Ten female piglets that had undergone a craniectomy were sonicated using a 220-kHz transcranial MRgFUS system over an acoustic energy range of 5600-14,000 J. For each piglet, a long-duration sonication (40-second duration) was performed on the right thalamus, and a short sonication (20-second duration) was performed on the left thalamus. An acoustic power range of 140-300 W was used for long-duration sonications and 300-700 W for short-duration sonications. Signals collected by 2 passive cavitation detectors were stored in memory during each sonication, and any subsequent cavitation activity was integrated within the bandwidth of the detectors. Real-time 2D MR thermometry was performed during the sonications. T1-weighted, T2-weighted, gradient-recalled echo, and diffusion-weighted imaging MRI was performed after treatment to assess the lesions. The piglets were killed immediately after the last series of posttreatment MR images were obtained. Their brains were harvested, and histological examinations were then performed to further evaluate the lesions. Two types of lesions were induced: thermal ablation lesions, as evidenced by an acute ischemic infarction on MRI and histology, and hemorrhagic lesions, associated with inertial cavitation. Passive cavitation signals exhibited 3 main patterns identified as

  11. Acute whole-body cooling for exercise-induced hyperthermia: a systematic review.

    Science.gov (United States)

    McDermott, Brendon P; Casa, Douglas J; Ganio, Matthew S; Lopez, Rebecca M; Yeargin, Susan W; Armstrong, Lawrence E; Maresh, Carl M

    2009-01-01

    To assess existing original research addressing the efficiency of whole-body cooling modalities in the treatment of exertional hyperthermia. During April 2007, we searched MEDLINE, EMBASE, Scopus, SportDiscus, CINAHL, and Cochrane Reviews databases as well as ProQuest for theses and dissertations to identify research studies evaluating whole-body cooling treatments without limits. Key words were cooling, cryotherapy, water immersion, cold-water immersion, ice-water immersion, icing, fanning, bath, baths, cooling modality, heat illness, heat illnesses, exertional heatstroke, exertional heat stroke, heat exhaustion, hyperthermia, hyperthermic, hyperpyrexia, exercise, exertion, running, football, military, runners, marathoner, physical activity, marathoning, soccer, and tennis. Two independent reviewers graded each study on the Physiotherapy Evidence Database (PEDro) scale. Seven of 89 research articles met all inclusion criteria and a minimum score of 4 out of 10 on the PEDro scale. After an extensive and critical review of the available research on whole-body cooling for the treatment of exertional hyperthermia, we concluded that ice-water immersion provides the most efficient cooling. Further research comparing whole-body cooling modalities is needed to identify other acceptable means. When ice-water immersion is not possible, continual dousing with water combined with fanning the patient is an alternative method until more advanced cooling means can be used. Until future investigators identify other acceptable whole-body cooling modalities for exercise-induced hyperthermia, ice-water immersion and cold-water immersion are the methods proven to have the fastest cooling rates.

  12. Interstitial hyperthermia using 8 MHz radiofrequency and stereotaxic brachytherapy for brain tumors

    International Nuclear Information System (INIS)

    Nishimura, Satoshi

    1990-01-01

    As a preliminary study of the interstitial hyperthermia combined with interstitial irradiation (brachytherapy) for the treatment of malignant brain tumors, we performed an experiment of interstitial hyperthermia of brain tissue of dogs. Nine afterloading tubes, four for needle electrodes and five for thermisters, were inserted in the brain tissue of dogs. Rise and stability of temperature were ascertained, and clinical safety was confirmed. Thereafter this combined therapy was applied on seven cases, in which three were malignant gliomas and four were metastatic tumors. Through the guide tubes, 192 Ir thin wires were implanted stereotaxically, and interstitial irradiation was carried out. After removal of 192 Ir wires, needle electrodes were inserted through the same tubes, and also a thermister was guided at the center of electrodes. And interstitial hyperthermia using 8 MHz radiofrequency was carried out. The results of the treatment were evaluated with CT scan based on criteria of the Japan Neurological Society. In cases of malignant gliomas, 2 PRs (partial remission), and 1 NC (no change) were obtained. In cases of metastatic tumors, 1 CR (complete remission), 2 PRs, 1 NC were obtaind. In cases of NCs, progression of tumors have been suppressed for 10 and 17 months, and still alive. As complication, transient worsening of neurological symptoms were observed in four cases (increased paresis: two cases, nausea and vomiting: two cases). The author have had an impression that interstitial hyperthermia combined with interstitial irradiation might become an effective means of treatment of brain tumors. (author)

  13. A randomized clinical trial of hyperthermia and radiation versus radiation alone for superficially located cancers

    International Nuclear Information System (INIS)

    Egawa, Sunao; Tsukiyama, Iwao; Watanabe, Shaw

    1989-01-01

    A randomized clinical trial was performed in order to evaluate the effect of combined hyperthermia and radiation for superficially located tumors. Ten institutions participated in this study and 92 evaluable patients were entered from September 1985 to March 1987 (44 patients for radiation plus hyperthermia and 48 for radiation only). Superficially located tumors, more than 3x3 cm in diameter, regardless of whether they were primary or metastatic, and of their histology, were included in the study. Radiotherapy was performed by the conventional fractionation method (2 Gyx5/week). Hyperthermia was conducted once a week. There was no statistical difference between the two groups regarding age, sex, the distribution of tumors and treatment parameters. The complete response (CR) and partial response (PR) rate for the hyperthermia plus radiation group was 81.8%, while the rate for the radiation alone group was 62.6% (p<0.05). Six factors were selected for analysis of the above effect by a multiple logistic model. Sex contributed the most (p=0.001), then the site of the tumor (p=0.016) and the method of treatment (p=0.023). Sex and the site influenced the results. Age, irradiation dose and frequency and duration of heating were not significant factors for response to treatment. (author)

  14. Effects of methylglyoxal bis(guanylhydrazone) on tumour and skin responses to hyperthermia in mice

    International Nuclear Information System (INIS)

    Miyakoshi, J.; Oda, W.; Inagaki, C.; Hiraoka, M.; Takahashi, M.; Abe, M.

    1984-01-01

    Effects of methylglyoxal bis(guanylhydrazone) (MGBG) on tumour and skin responses to hyperthermia (42degC) were examined in C3H mice. MGBG (50 mg/kg) was administered intraperitoneally to mice 4 hours before hyperthermic treatment. The tumour (FM3A) growth time was elongated by an amount dependent on the exposure time of treatment at 42degC (60, 90 and 120 min). Pre-treatment of mice with MGBG (50 mg/kg, i.p.) apparently further lengthened the tumour growth time after treatment at 42degC. No significant damage of foot skin was caused by 42degC hyperthermia. Pre-treatment with MGBG did not make the foot skin susceptible to the heating. From these findings, it can be considered that MGBG or related less-toxic compounds may have a clinical advantage for the mild (42degC) hyperthermic treatment in cancer therapy. (author)

  15. Effects of methylglyoxal bis(guanylhydrazone) on tumour and skin responses to hyperthermia in mice

    Energy Technology Data Exchange (ETDEWEB)

    Miyakoshi, J.; Oda, W.; Inagaki, C. (Kyoto Coll. of Pharmacy (Japan)); Hiraoka, M.; Takahashi, M.; Abe, M. (Kyoto Univ. (Japan). Faculty of Medicine)

    1984-09-01

    Effects of methylglyoxal bis(guanylhydrazone) (MGBG) on tumour and skin responses to hyperthermia (42degC) were examined in C3H mice. MGBG (50 mg/kg) was administered intraperitoneally to mice 4 hours before hyperthermic treatment. The tumour (FM3A) growth time was elongated by an amount dependent on the exposure time of treatment at 42degC (60, 90 and 120 min). Pre-treatment of mice with MGBG (50 mg/kg, i.p.) apparently further lengthened the tumour growth time after treatment at 42degC. No significant damage of foot skin was caused by 42degC hyperthermia. Pre-treatment with MGBG did not make the foot skin susceptible to the heating. From these findings, it can be considered that MGBG or related less-toxic compounds may have a clinical advantage for the mild (42degC) hyperthermic treatment in cancer therapy.

  16. Prospective phase II trial of regional hyperthermia and whole liver irradiation for numerous chemorefratory liver metastases from colerectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Jeong Il; Park, Hee Chul; Choi, Doo Ho [Dept. of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); and others

    2016-03-15

    A prospective phase II trial was conducted to evaluate the effectiveness and toxicity of regional hyperthermia and whole liver irradiation (WLI) for numerous chemorefractory liver metastases from colorectal cancer. Enrolled patients had numerous chemorefractory hepatic metastases from colorectal cancer. Five sessions of hyperthermia and seven fractions of 3-gray WLI were planned. Health-related quality of life (HRQoL) was determined using the Korean version of the European Organization for Research and Treatment of Cancer quality of life questionnaire C-30 and the Functional Assessment of Cancer Therapy-Hepatobiliary version 4.0. Objective and pain response was evaluated. A total of 12 patients consented to the study and the 10 who received WLI and hyperthermia were analyzed. WLI was completed as planned in nine patients and hyperthermia in eight. Pain response was partial in four patients and stable in four. Partial objective response was achieved in three patients (30.0%) and stable disease was seen in four patients at the 1-month follow-up. One patient died 1 month after treatment because of respiratory failure related to pleural metastasis progression. Other grade III or higher toxicities were detected in three patients; however, all severe toxicities were related to disease progression rather than treatment. No significant difference in HRQoL was noted at the time of assessment for patients who were available for questionnaires. Combined WLI and hyperthermia were well tolerated without severe treatment-related toxicity with a promising response from numerous chemorefractory hepatic metastases from colorectal cancer.

  17. Polymer coated fiber Bragg grating thermometry for microwave hyperthermia.

    Science.gov (United States)

    Saxena, Indu Fiesler; Hui, Kaleo; Astrahan, Melvin

    2010-09-01

    Measuring tissue temperature distribution during electromagnetically induced hyperthermia (HT) is challenging. High resistance thermistors with nonmetallic leads have been used successfully in commercial HT systems for about three decades. The single 1 mm thick temperature sensing element is mechanically moved to measure tissue temperature distributions. By employing a single thermometry probe containing a fixed linear sensor array temperature, distributions during therapy can be measured with greater ease. While the first attempts to use fiber Bragg grating (FBG) technology to obtain multiple temperature points along a single fiber have been reported, improvement in the detection system's stability were needed for clinical applications. The FBG temperature sensing system described here has a very high temporal stability detection system and an order of magnitude faster readout than commercial systems. It is shown to be suitable for multiple point fiber thermometry during microwave hyperthermia when compared to conventional mechanically scanning probe HT thermometry. A polymer coated fiber Bragg grating (PFBG) technology is described that provides a number of FBG thermometry locations along the length of a single optical fiber. The PFBG probe developed is tested under simulated microwave hyperthermia treatment to a tissue equivalent phantom. Two temperature probes, the multiple PFBG sensor and the Bowman probe, placed symmetrically with respect to a microwave antenna in a tissue phantom are subjected to microwave hyperthermia. Measurements are made at start of HT and 85 min later, when a 6 degrees C increase in temperature is registered by both probes, as is typical in clinical HT therapy. The optical fiber multipoint thermometry probe performs highly stable, real-time thermometry updating each multipoint thermometry scan over a 5 cm length every 2 s. Bowman probe measurements are acquired simultaneously for comparison. In addition, the PFBG sensor's detection

  18. Mild hyperthermia can induce adaptation to cytogenetic damage caused by subsequent X irradiation

    International Nuclear Information System (INIS)

    Cai, Lu.; Jiang, Jie.

    1995-01-01

    Many low-level environmental agents are able to induce an increased resistance to subsequent mutagenic effects induced by ionizing radiation. In this paper, an induced cytogenetic adaptation to radiation in human lymphocytes was studied with mild hyperthermia as the adaptive treatment and compared with that induced by low-dose radiation. We found that this adaptation could be induced not only in PHA-stimulated human lymphocytes (at 14, 38 and 42 h after addition of PHA), but also in unstimulated G 0 -phase cells (before addition of PHA) by mild hyperthermia (41 degrees C for 1 h) as well as 50 mGy X rays. When the two adaptive treatments were combined, no additive effects on the magnitude of the adaptation induced were observed, suggesting that low-dose radiation and hyperthermia may share one mechanism of induction of adaptation to cytogenetic damage. Some mechanisms which may be involved in the induction of adaptation to cytogenetic damage by low-dose radiation are discussed and compared with the effects of mild hyperthermia in inducing thermotolerance and radioresistance. 56 refs., 4 figs., 3 tabs

  19. TU-AB-BRA-07: Distortion-Free 3D Diffusion MRI On An MRI-Guided Radiotherapy System for Longitudinal Tumor Response Assessment

    International Nuclear Information System (INIS)

    Gao, Y; Yang, Y; Rangwala, N; Cao, M; Low, D; Hu, P

    2016-01-01

    Purpose: To develop a reliable, 3D distortion-free diffusion MRI technique for longitudinal tumor response assessment and MRI-guided adaptive radiotherapy(RT). Methods: A diffusion prepared 3D turbo spin echo readout (DP-TSE) sequence was developed and compared with the conventional diffusion-weighted single-shot echo-planar-imaging (DW-ssEPI) sequence in a commercially available diffusion phantom, and one head-and-neck and one brain cancer patient on an MRI-guided RT system (ViewRay). In phantom study, the geometric fidelity was quantified as the ratio between the left-right (RL) and anterior-posterior (AP) dimension. Ten slices were measured on DP-TSE, DW-ssEPI and standard TSE images where the later was used as the geometric reference. ADC accuracy was verified at both 0°C (reference ADC available) and room temperature with a range of diffusivity between 0.35 and 2.0*10"−"3mm"2/s. The ADC reproducibility was assessed based on 8 room-temperature measurements on 6 different days. In the pilot single-slice in-vivo study, CT images were used as the geometric reference, and ADC maps from both diffusion sequences were compared. Results: Distortion and susceptive-related artifact were severe in DW-ssEPI, with significantly lower RL/AP ratio (0.9579±0.0163) than DP-TSE (0.9990±0.0031) and TSE (0.9995±0.0031). ADCs from the two diffusion sequences both matched well with the vendor-provided values at 0°C; however DW-ssEPI fails to provide accurate ADC for high diffusivity vials at room temperature due to high noise level (10 times higher than DP-TSE). The DP-TSE sequence had excellent ADC reproducibility with <4% ADC variation among 8 separate measurements. In patient study, DP-TSE exhibited substantially improved geometric reliability. ROI analysis in ADC maps generated from DP-TSE and DW-ssEPI showed <5% difference where high b-value images were excluded from the latter approach due to excessive noise level. Conclusion: A diffusion MRI sequence with excellent

  20. TU-AB-BRA-07: Distortion-Free 3D Diffusion MRI On An MRI-Guided Radiotherapy System for Longitudinal Tumor Response Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Y; Yang, Y; Rangwala, N; Cao, M; Low, D; Hu, P [UCLA School of Medicine, Los Angeles, CA (United States)

    2016-06-15

    Purpose: To develop a reliable, 3D distortion-free diffusion MRI technique for longitudinal tumor response assessment and MRI-guided adaptive radiotherapy(RT). Methods: A diffusion prepared 3D turbo spin echo readout (DP-TSE) sequence was developed and compared with the conventional diffusion-weighted single-shot echo-planar-imaging (DW-ssEPI) sequence in a commercially available diffusion phantom, and one head-and-neck and one brain cancer patient on an MRI-guided RT system (ViewRay). In phantom study, the geometric fidelity was quantified as the ratio between the left-right (RL) and anterior-posterior (AP) dimension. Ten slices were measured on DP-TSE, DW-ssEPI and standard TSE images where the later was used as the geometric reference. ADC accuracy was verified at both 0°C (reference ADC available) and room temperature with a range of diffusivity between 0.35 and 2.0*10{sup −3}mm{sup 2}/s. The ADC reproducibility was assessed based on 8 room-temperature measurements on 6 different days. In the pilot single-slice in-vivo study, CT images were used as the geometric reference, and ADC maps from both diffusion sequences were compared. Results: Distortion and susceptive-related artifact were severe in DW-ssEPI, with significantly lower RL/AP ratio (0.9579±0.0163) than DP-TSE (0.9990±0.0031) and TSE (0.9995±0.0031). ADCs from the two diffusion sequences both matched well with the vendor-provided values at 0°C; however DW-ssEPI fails to provide accurate ADC for high diffusivity vials at room temperature due to high noise level (10 times higher than DP-TSE). The DP-TSE sequence had excellent ADC reproducibility with <4% ADC variation among 8 separate measurements. In patient study, DP-TSE exhibited substantially improved geometric reliability. ROI analysis in ADC maps generated from DP-TSE and DW-ssEPI showed <5% difference where high b-value images were excluded from the latter approach due to excessive noise level. Conclusion: A diffusion MRI sequence with

  1. Hyperthermia: an effective strategy to induce apoptosis in cancer cells.

    Science.gov (United States)

    Ahmed, Kanwal; Tabuchi, Yoshiaki; Kondo, Takashi

    2015-11-01

    Heat has been used as a medicinal and healing modality throughout human history. The combination of hyperthermia (HT) with radiation and anticancer agents has been used clinically and has shown positive results to a certain extent. However, the clinical results of HT treatment alone have been only partially satisfactory. Cell death following HT treatment is a function of both temperature and treatment duration. HT induces cancer cell death through apoptosis; the degree of apoptosis and the apoptotic pathway vary in different cancer cell types. HT-induced reactive oxygen species production are responsible for apoptosis in various cell types. However, the underlying mechanism of signal transduction and the genes related to this process still need to be elucidated. In this review, we summarize the molecular mechanism of apoptosis induced by HT, enhancement of heat-induced apoptosis, and the genetic network involved in HT-induced apoptosis.

  2. Re-irradiation and hyperthermia after surgery for recurrent breast cancer

    International Nuclear Information System (INIS)

    Linthorst, Marianne; Geel, Albert N. van; Baaijens, Margreet; Ameziane, Ali; Ghidey, Wendim; Rhoon, Gerard C. van; Zee, Jacoba van der

    2013-01-01

    Purpose: Evaluation of efficacy and side effects of combined re-irradiation and hyperthermia electively or for subclinical disease in the management of locoregional recurrent breast cancer. Methods and materials: Records of 198 patients with recurrent breast cancer treated with re-irradiation and hyperthermia from 1993 to 2010 were reviewed. Prior treatments included surgery (100%), radiotherapy (100%), chemotherapy (42%), and hormonal therapy (57%). Ninety-one patients were treated for microscopic residual disease following resection or systemic therapy and 107 patients were treated electively for areas at high risk for local recurrences. All patients were re-irradiated to 28–36 Gy (median 32) and treated with 3–8 hyperthermia treatments (mean 4.36). Forty percent of the patients received concurrent hormonal therapy. Patient and tumor characteristics predictive for actuarial local control (LC) and toxicity were studied in univariate and multivariate analysis. Results: The median follow-up was 42 months. Three and 5 year LC-rates were 83% and 78%. Mean of T90 (tenth percentile of temperature distribution), maximum and average temperatures were 39.8 °C, 43.6 °C, and 41.2 °C, respectively. Mean of the cumulative equivalent minutes (CEM43) at T90 was 4.58 min. Number of previous chemotherapy and surgical procedures were most predictive for LC. Cumulative incidence of grade 3 and 4 late toxicity at 5 years was 11.9%. The number of thermometry sensors and depth of treatment volume were associated with acute hyperthermia toxicity. Conclusions: The combination of re-irradiation and hyperthermia results in a high LC-rate with acceptable toxicity

  3. Effects of hyperthermia and radiation on mouse testis stem cells

    International Nuclear Information System (INIS)

    Reid, B.O.; Mason, K.A.; Withers, H.R.; West, J.

    1981-01-01

    The response of mouse testis stem cells to hyperthermia and combined hyperthermia-radiation treatments was assayed by spermatogenic colony regrowth, sperm head counts, testis weight loss, and fertility. With the use of spermatogenic colony assay, thermal enhancement ratios at an isosurvival level of 0.1 were 1.27 at 41 degrees, 1.80 at 42 degrees, and 3.97 at 43 degrees for testes exposed to heat for 30 min prior to irradiation. Sperm head counts were reduced by heat alone from a surviving fraction of 0.58 at 41 degrees to 0.003 at 42.5-43.5 degrees. Curves for sperm head survival measured 56 days after the testes had been heated for 30 min prior to irradiation were biphasic and showed a progressive downward displacement to lower survival with increasing temperature. The 41, 42, and 43 degrees curves were displaced downward by factors of 2, 58, and 175, respectively. The proportion of animals remaining sterile after 30 min of heat (41-43 degrees) and the median sterility period in days increased with increasing temperature. The minimum sperm count necessary to regain fertility was 13% of the normal mouse level

  4. Immunogenicity of ascites tumor cells following in vitro hyperthermia

    International Nuclear Information System (INIS)

    Dickson, J.A.; Jasiewicz, M.L.; Simpson, A.C.

    1982-01-01

    The concept that host immunization may be achieved by heat-induced antigenic modifications of cancer cells and/or the release of immunogenic products by dead or dying tumor cells following in vitro heating was examined. Ehrlich ascites cells were used, inasmuch as it was claimed that in vitro hyperthermia increased the immunogenicity of these cells. Tumor cell populations of different viability were obtained by heating Ehrlich cells at 42.5 degrees, 45 degrees, or 60 degrees C. Viable and nonviable cells were separated by Ficoll-Hypaque density centrifugation; viable nonreplicating cells were obtained by treatment with mitomycin C. Cell populations of different viability after heating were left to die slowly over 3 days at 37 degrees C. Swiss TO mice were then given injections of the treated cells and/or medium. No survival benefit occurred in mice inoculated with any of these different components and then challenged with viable tumor cells. Injection of irradiated cells, however, did produce host immunity. Similarly, D23 rat hepatoma ascites cells produced host immunity after 15,000 rad but not after heating. The claim that in vitro hyperthermia increases the immunogenicity of tumor cells was not confirmed

  5. Microwave hyperthermia enhancement of methotrexate absorption in rat brains

    International Nuclear Information System (INIS)

    Lin, J.C.; Yuen, M.K.; Jung, D.T.

    1987-01-01

    The author studied enhanced absorption of methotrexate (MTX) in brains of male Wistar (10 weeks old, 500g) subjected to microwave hyperthermia. The rat was anesthetized using 40 mg/kg of sodium pentobarbital, IP and was placed in a stereotaxic head holder. Microwave energy (2450 MHz, 2.6 W/cm/sup 2/, CW) were applied directly to the left side of the rat's head by a coaxial applicator for 20 min. The body temperature was kept at 37.8 0 C. The brain temperature recorded in a similar group of animals using a Vitek probe was about 45 0 C. Three different MTX dosages, 50, 100 and 200 mg/kg, were injected intravenously immediately following microwave irradiation into three groups of rats in 1.5, 3 and 6 min., respectively. MTX was allowed to circulate for five min. before brains were removed for analysis. Standard HPLC procedures were applied to samples from anterior and posterior left hemisphere of the cerebrum, and the cerebellum. Samples from the right hemisphere were used for controls. The average absorption at the posterior left hemisphere was found to be 2.4, 9.6 and 12.4μg of MTX/g of brain tissue for 50, 100 and 200 mg/kg, respectively. These results indicate that MTX absorption is significantly increased in rat brains subjected to microwave hyperthermia treatment

  6. Production of lesions in rabbit spinal cord with microwave hyperthermia

    International Nuclear Information System (INIS)

    Sutton, C.H.; Popovic, P.

    1984-01-01

    The use of a variety of injury models in different species to produce spinal cord lesions by trauma or ischemia has often given rise to conflicting or inconclusive data. A new model has been developed in rabbits. Spinal cord lesions were produced in selected spinal cord segments of male New Zealand white rabbits by non-invasive irradiation with microwaves in the near field at 915 MHz. Graded injuries of predictable severity can be produced by the non-invasive induction of moderate hyperthermia in the thoracic spinal cord at precise dosage levels of temperature elevation and duration. Histological changes in microwave-induced hyperthermia closely parallel those seen in traumatic lesions of the human spinal cord, as well as those produced in animals with the classical weight-drop method of Allen. In addition to grading the spinal cord lesions with respect to residual neurological function, dose-response observations made with somatosensory evoked responses, blood-spinal cord barrier tracers, and neurohistological and enzyme histochemical preparations, suggest that it will be possible to use this approach to develop a standardized, calibrated model in rabbits to evaluate the efficacy of new therapeutic modalities for the treatment of spinal cord injury

  7. Clinical Study Pathologic Findings in MRI-Guided Needle Core Biopsies of the Breast in Patients with Newly Diagnosed Breast Cancer

    International Nuclear Information System (INIS)

    Siziopikou, K.P.; Jokich, P.; Cobleigh, M.

    2011-01-01

    The role of MRI in the management of breast carcinoma is rapidly evolving from its initial use for specific indications only to a more widespread use on all women with newly diagnosed early stage breast cancer. However, there are many concerns that such widespread use is premature since detailed correlation of MRI findings with the underlying histopathology of the breast lesions is still evolving and clear evidence for improvements in management and overall prognosis of breast cancer patients evaluated by breast MRI after their initial cancer diagnosis is lacking. In this paper, we would like to bring attention to a benign lesion that is frequently present on MRI-guided breast biopsies performed on suspicious MRI findings in the affected breast of patients with a new diagnosis of breast carcinoma

  8. Dose-volume effect relationships for late rectal morbidity in patients treated with chemoradiation and MRI-guided adaptive brachytherapy for locally advanced cervical cancer: Results from the prospective multicenter EMBRACE study

    DEFF Research Database (Denmark)

    Mazeron, Renaud; Fokdal, Lars U; Kirchheiner, Kathrin

    2016-01-01

    Purpose To establish dose volume–effect relationships predicting late rectal morbidity in cervix cancer patients treated with concomitant chemoradiation and MRI-guided adaptive brachytherapy (IBABT) within the prospective EMBRACE study. Material and method All patients were treated with curative ...

  9. Early observed transient prostate-specific antigen elevations on a pilot study of external beam radiation therapy and fractionated MRI guided High Dose Rate brachytherapy boost

    International Nuclear Information System (INIS)

    Singh, Anurag K; Godette, Denise J; Stall, Bronwyn R; Coleman, C Norman; Camphausen, Kevin; Ménard, Cynthia; Guion, Peter; Susil, Robert C; Citrin, Deborah E; Ning, Holly; Miller, Robert W; Ullman, Karen; Smith, Sharon; Crouse, Nancy Sears

    2006-01-01

    To report early observation of transient PSA elevations on this pilot study of external beam radiation therapy and magnetic resonance imaging (MRI) guided high dose rate (HDR) brachytherapy boost. Eleven patients with intermediate-risk and high-risk localized prostate cancer received MRI guided HDR brachytherapy (10.5 Gy each fraction) before and after a course of external beam radiotherapy (46 Gy). Two patients continued on hormones during follow-up and were censored for this analysis. Four patients discontinued hormone therapy after RT. Five patients did not receive hormones. PSA bounce is defined as a rise in PSA values with a subsequent fall below the nadir value or to below 20% of the maximum PSA level. Six previously published definitions of biochemical failure to distinguish true failure from were tested: definition 1, rise >0.2 ng/mL; definition 2, rise >0.4 ng/mL; definition 3, rise >35% of previous value; definition 4, ASTRO defined guidelines, definition 5 nadir + 2 ng/ml, and definition 6, nadir + 3 ng/ml. Median follow-up was 24 months (range 18–36 mo). During follow-up, the incidence of transient PSA elevation was: 55% for definition 1, 44% for definition 2, 55% for definition 3, 33% for definition 4, 11% for definition 5, and 11% for definition 6. We observed a substantial incidence of transient elevations in PSA following combined external beam radiation and HDR brachytherapy for prostate cancer. Such elevations seem to be self-limited and should not trigger initiation of salvage therapies. No definition of failure was completely predictive

  10. TU-H-BRA-01: The Physics of High Power Radiofrequency Isolation in a Novel Compact Linear Accelerator Based MRI Guided Radiation Therapy System

    Energy Technology Data Exchange (ETDEWEB)

    Lamb, J; Low, D [University of California, Los Angeles, Los Angeles, CA (United States); Mutic, S [Washington University School of Medicine, Saint Louis, MO (United States); Shvartsman, S; Chmielewski, T; Fought, G; Sharma, A; Dempsey, J [ViewRay, Inc., Oakwood Village, OH (United States)

    2016-06-15

    Purpose: To develop a method for isolating the radiofrequency waves emanating from linear accelerator components from the magnetic resonance imaging (MRI) system of an integrated MRI-linac. Methods: An MRI-guided radiation therapy system has been designed that integrates a linear accelerator with simultaneous MR imaging. The radiofrequency waves created by the accelerating process would degrade MR image quality, so a method for containing the radiofrequency waves and isolating the MR imager from them was developed. The linear accelerator radiofrequency modulator was placed outside the room, so a filter was designed to eliminate the radiofrequency corresponding to the proton Larmour frequency of 14.7 MHz. Placing the radiofrequency emitting components in a typical Faraday cage would have reduced the radiofrequency emissions, but the design would be susceptible to small gaps in the shield due to the efficiency of the Faraday cage reflecting internal radiofrequency emissions. To reduce internal radiofrequency reflections, the Faraday cage was lined with carbon fiber sheets. Carbon fiber has the property of attenuating the radiofrequency energy so that the overall radiofrequency field inside the Faraday cage is reduced, decreasing any radiofrequency energy emitted from small gaps in the cage walls. Results: Within a 1.2 MHz band centered on the Larmor frequency, the radiofrequency (RF) leakage from the Faraday cage was measured to be −90 dB with no RF on, −40 dB with the RF on and no shield, returning to −90 dB with the RF on and shields in place. The radiofrequency filter attenuated the linear accelerator modulator emissions in the 14.7 MHz band by 70 dB. Conclusions: One of the major challenges in designing a compact linear accelerator based MRI-guided radiation therapy system, that of isolating the high power RF system from the MRI, has been solved. The measured radiofrequency emissions are sufficiently small to enable system integration. This research was

  11. SU-E-J-198: Out-Of-Field Dose and Surface Dose Measurements of MRI-Guided Cobalt-60 Radiotherapy

    International Nuclear Information System (INIS)

    Lamb, J; Agazaryan, N; Cao, M; Low, D; Thomas, D; Yang, Y

    2015-01-01

    Purpose: To measure quantities of dosimetric interest in an MRI-guided cobalt radiotherapy machine that was recently introduced to clinical use. Methods: Out-of-field dose due to photon scatter and leakage was measured using an ion chamber and solid water slabs mimicking a human body. Surface dose was measured by irradiating stacks of radiochromic film and extrapolating to zero thickness. Electron out-of-field dose was characterized using solid water slabs and radiochromic film. Results: For some phantom geometries, up to 50% of Dmax was observed up to 10 cm laterally from the edge of the beam. The maximum penetration was between 1 and 2 mm in solid water, indicating an electron energy not greater than approximately 0.4 MeV. Out-of-field dose from photon scatter measured at 1 cm depth in solid water was found to fall to less than 10% of Dmax at a distance of 1.2 cm from the edge of a 10.5 × 10.5 cm field, and less that 1% of Dmax at a distance of 10 cm from field edge. Surface dose was measured to be 8% of Dmax. Conclusion: Surface dose and out-of-field dose from the MRIguided cobalt radiotherapy machine was measured and found to be within acceptable limits. Electron out-of-field dose, an effect unique to MRI-guided radiotherapy and presumed to arise from low-energy electrons trapped by the Lorentz force, was quantified. Dr. Low is a member of the scientific advisory board of ViewRay, Inc

  12. TU-H-BRA-01: The Physics of High Power Radiofrequency Isolation in a Novel Compact Linear Accelerator Based MRI Guided Radiation Therapy System

    International Nuclear Information System (INIS)

    Lamb, J; Low, D; Mutic, S; Shvartsman, S; Chmielewski, T; Fought, G; Sharma, A; Dempsey, J

    2016-01-01

    Purpose: To develop a method for isolating the radiofrequency waves emanating from linear accelerator components from the magnetic resonance imaging (MRI) system of an integrated MRI-linac. Methods: An MRI-guided radiation therapy system has been designed that integrates a linear accelerator with simultaneous MR imaging. The radiofrequency waves created by the accelerating process would degrade MR image quality, so a method for containing the radiofrequency waves and isolating the MR imager from them was developed. The linear accelerator radiofrequency modulator was placed outside the room, so a filter was designed to eliminate the radiofrequency corresponding to the proton Larmour frequency of 14.7 MHz. Placing the radiofrequency emitting components in a typical Faraday cage would have reduced the radiofrequency emissions, but the design would be susceptible to small gaps in the shield due to the efficiency of the Faraday cage reflecting internal radiofrequency emissions. To reduce internal radiofrequency reflections, the Faraday cage was lined with carbon fiber sheets. Carbon fiber has the property of attenuating the radiofrequency energy so that the overall radiofrequency field inside the Faraday cage is reduced, decreasing any radiofrequency energy emitted from small gaps in the cage walls. Results: Within a 1.2 MHz band centered on the Larmor frequency, the radiofrequency (RF) leakage from the Faraday cage was measured to be −90 dB with no RF on, −40 dB with the RF on and no shield, returning to −90 dB with the RF on and shields in place. The radiofrequency filter attenuated the linear accelerator modulator emissions in the 14.7 MHz band by 70 dB. Conclusions: One of the major challenges in designing a compact linear accelerator based MRI-guided radiation therapy system, that of isolating the high power RF system from the MRI, has been solved. The measured radiofrequency emissions are sufficiently small to enable system integration. This research was

  13. TU-H-BRA-02: The Physics of Magnetic Field Isolation in a Novel Compact Linear Accelerator Based MRI-Guided Radiation Therapy System

    International Nuclear Information System (INIS)

    Low, D; Mutic, S; Shvartsman, S; Chmielewski, T; Fought, G; Sharma, A; Dempsey, J

    2016-01-01

    Purpose: To develop a method for isolating the MRI magnetic field from field-sensitive linear accelerator components at distances close to isocenter. Methods: A MRI-guided radiation therapy system has been designed that integrates a linear accelerator with simultaneous MR imaging. In order to accomplish this, the magnetron, port circulator, radiofrequency waveguide, gun driver, and linear accelerator needed to be placed in locations with low magnetic fields. The system was also required to be compact, so moving these components far from the main magnetic field and isocenter was not an option. The magnetic field sensitive components (exclusive of the waveguide) were placed in coaxial steel sleeves that were electrically and mechanically isolated and whose thickness and placement were optimized using E&M modeling software. Six sets of sleeves were placed 60° apart, 85 cm from isocenter. The Faraday effect occurs when the direction of propagation is parallel to the magnetic RF field component, rotating the RF polarization, subsequently diminishing RF power. The Faraday effect was avoided by orienting the waveguides such that the magnetic field RF component was parallel to the magnetic field. Results: The magnetic field within the shields was measured to be less than 40 Gauss, significantly below the amount needed for the magnetron and port circulator. Additional mu-metal was employed to reduce the magnetic field at the linear accelerator to less than 1 Gauss. The orientation of the RF waveguides allowed the RT transport with minimal loss and reflection. Conclusion: One of the major challenges in designing a compact linear accelerator based MRI-guided radiation therapy system, that of creating low magnetic field environments for the magnetic-field sensitive components, has been solved. The measured magnetic fields are sufficiently small to enable system integration. This work supported by ViewRay, Inc.

  14. TU-H-BRA-02: The Physics of Magnetic Field Isolation in a Novel Compact Linear Accelerator Based MRI-Guided Radiation Therapy System

    Energy Technology Data Exchange (ETDEWEB)

    Low, D [UCLA, Los Angeles, CA (United States); Mutic, S [Washington University School of Medicine, Saint Louis, MO (United States); Shvartsman, S; Chmielewski, T; Fought, G; Sharma, A; Dempsey, J [ViewRay, Inc., Oakwood Village, OH (United States)

    2016-06-15

    Purpose: To develop a method for isolating the MRI magnetic field from field-sensitive linear accelerator components at distances close to isocenter. Methods: A MRI-guided radiation therapy system has been designed that integrates a linear accelerator with simultaneous MR imaging. In order to accomplish this, the magnetron, port circulator, radiofrequency waveguide, gun driver, and linear accelerator needed to be placed in locations with low magnetic fields. The system was also required to be compact, so moving these components far from the main magnetic field and isocenter was not an option. The magnetic field sensitive components (exclusive of the waveguide) were placed in coaxial steel sleeves that were electrically and mechanically isolated and whose thickness and placement were optimized using E&M modeling software. Six sets of sleeves were placed 60° apart, 85 cm from isocenter. The Faraday effect occurs when the direction of propagation is parallel to the magnetic RF field component, rotating the RF polarization, subsequently diminishing RF power. The Faraday effect was avoided by orienting the waveguides such that the magnetic field RF component was parallel to the magnetic field. Results: The magnetic field within the shields was measured to be less than 40 Gauss, significantly below the amount needed for the magnetron and port circulator. Additional mu-metal was employed to reduce the magnetic field at the linear accelerator to less than 1 Gauss. The orientation of the RF waveguides allowed the RT transport with minimal loss and reflection. Conclusion: One of the major challenges in designing a compact linear accelerator based MRI-guided radiation therapy system, that of creating low magnetic field environments for the magnetic-field sensitive components, has been solved. The measured magnetic fields are sufficiently small to enable system integration. This work supported by ViewRay, Inc.

  15. MRI-guided periradicular nerve root infiltration therapy in low-field (0.23-T) MRI system using optical instrument tracking

    International Nuclear Information System (INIS)

    Sequeiros, Roberto Blanco; Ojala, Risto O.; Klemola, Rauli; Jyrkinen, Lasse; Tervonen, Osmo A.; Vaara, Teuvo J.

    2002-01-01

    The purpose of this study was to evaluate the feasibility of the MRI-guided periradicular nerve root infiltration therapy. Sixty-seven nerve root infiltrations under MRI guidance were done for 61 patients suffering from lumbosacral radicular pain. Informed consent was acquired from all patients. A 0.23-T open-MRI scanner with interventional tools (Outlook Proview, Philips Medical Systems, MR Technologies, Finland) was used. A surface coil was used in all cases. Nerve root infiltration was performed with MRI-compatible 20-G needle (Chiba type MReye, Cook, Bloomington, Ind.; or Manan type, MD Tech, Florida). The evaluation of clinical outcome was achieved with 6 months of clinical follow-up and questionnaire. The effect of nerve root infiltration to the radicular pain was graded: 1=good to excellent, i.e., no pain or not disturbing pain allowing normal physical activity at 3 months from the procedure; 2=temporary, i.e., temporary relief of pain; 3=no relief of pain; and 4=worsening of pain. As an adjunct to MRI-guided positioning of the needle the correct needle localization by the nerve root was confirmed with saline injection to nerve root channel and single-shot fast spin echo (SSFSE) imaging. The MRI guidance allowed adequate needle positioning in all but 1 case (98.5%). This failure was caused by degeneration-induced changes in anatomy. Of patients, 51.5% had good to excellent effect with regard to radicular pain from the procedure, 22.7% had temporary relief, 21.2% had no effect, and in 4.5% the pain worsened. Our results show that MRI guidance is accurate and safe in performing nerve root infiltration at lumbosacral area. The results of radicular pain relief from nerve root infiltration are comparable to CT or fluoroscopy studies on the subject. (orig.)

  16. Role of regional radiofrequency hyperthermia after hepatic artery block in the normal pit liver

    International Nuclear Information System (INIS)

    Luo Jingwei; Xu Guozhen; Xiong Jinghong; Liu Xiaoyun; Wang Weihu; Li Yexiong

    2003-01-01

    Objective: To study the temperature difference, tolerated high temperature, pathological changes between normal and blocked hepatic artery in radiofrequency hyperthermia for pig liver. Methods: Mature pig was used with iodine blocked right hepatic artery. Heat of the whole liver was given for 1 hour by SR-1000 radiofrequency hyperthermia with four thermocouple probes to measure the temperature of the right hepatic artery, right and left normal liver and rectum. Results: Temperature of blocked right liver increased by 10.2 degree C from 39.1 degree C to 49.3 degree C as compared with the left liver of which the temperature rose by 6.8 degree C from 39.7 degree C to 46.5 degree C but the temperature of right hepatic artery and rectum rose only by 3.3 degree C, 3.2 degree C respectively. After sacrificing the pig one week later, on lobe exploration, severe necrosis was observed in the right lobe but the left lobe was normal with a clear demarcation between the two lobes. Conclusions: Hepatic arterial iodine embolization potentiates radiofrequency hyperthermia in the liver. Liver with blocked artery showed conspicuous necrosis but liver with normal un-blocked artery was able to tolerate 46.5 degree C. This provides some evidence for the combination of regional hyperthermia and hepatic artery block in the treatment of advanced liver cancer

  17. Effects of hyperthermia and X-irradiation on mouse stromal tissue

    International Nuclear Information System (INIS)

    Wondergem, J.; Haveman, J.

    1986-01-01

    The sensitivity of normal stroma to heat, irradiation and heat combined with irradiation, was studied using the tumour bed effect (TBE) assay. Irradiation before implantation led to a TBE, dose dependent below 15 Gy, but remaining relatively constant above. The interval (0-90 days) between irradiation and tumour implantation did not influence the magnitude of the TBE. Hyperthermia with large heat doses (45-60 min at 44 0 C) before implantation may lead to a TBE. The interval between hyperthermia and tumour implantation was very important. Results showed that the recovery from heat-induced stromal damage is very rapid. When the interval between hyperthermia and tumour implantation was 10 days or longer, no TBE could be observed. Irradiation combined with large heat doses (30-60 min at 44 0 C) decreased the radiation-induced TBE. The combination of irradiation with mild heat treatments (15 min at 44 0 C) could lead to a larger TBE then after irradiation alone. When hyperthermia was given prior to irradiation, the interval between heat and irradiation proved to be very important. With large intervals (21 days or longer), TBE values were about the same as with irradiation alone. When heat was given after irradiation, irradiation-induced TBE was always reduced. (UK)

  18. Late response to whole-lung irradiation alone and with whole-body hyperthermia in dogs

    International Nuclear Information System (INIS)

    Gillette, S.M.; Gillette, E.L.; Dawson, C.A.

    1997-01-01

    The late effects of whole-lung irradiation with and without whole-body hyperthermia were studied in beagle dogs. The reference doses ranged from 18 to 49.5 Gy given in 1.5-Gy fractions over 6 weeks. Whole-body hyperthermia was given in three 2-h treatments to a deep rectal temperature of 42.0 degrees C. Radiation was given simultaneously with hyperthermia on those days. Physiological and histopathological responses were evaluated. Physiological changes included decreases in cardiac output, systemic blood pressure, dynamic compliance and serotonin uptake. Early changes included an increase in extravascular water and total protein in the lavage. These changes were considered mild, were compensated for and occurred only in dogs receiving doses of 40.5 Gy or greater given in 1.5-Gy fractions over 6 weeks. Histopathological change were typical of irradiated lung and included pleural fibrosis, interstitial fibrosis, fibrotic foci, and peribronchial and perivascular fibrosis. There was no enhancement of late injury to lung by hyperthermia seen in this study. 17 refs., 3 figs., 2 tabs

  19. SR-1000 radiofrequency chemo-hyperthermia for recurrent and metastatic peritoneo-pelvic malignant tumors

    International Nuclear Information System (INIS)

    Luo Jingwei; Xiong Jinghong; Xu Guozhen; Yu Zihao; Li Yexiong; Yin Weibo

    2002-01-01

    Objective: To evaluate the efficacy and tolerance of intraperitoneal chemo-hyperthermia (IPCH) with SR-1000 radiofrequency (RF) for recurrent or metastatic peritoneo-pelvic malignant tumors. Methods: Twenty-one patients with recurrent or metastatic peritoneo-pelvic malignant tumors received chemo-hyperthermia, with 9 having local pain and 14 having ascites. The Karnofsky scores were 40-80. After abdominal cavity aspiration and infusion of hot NS and chemotherapeutic agents, the temperature of abdominal cavity was increased and maintained at 40.5-42.5 degree C for 60-90 minutes with SR-1000 RF. Hyperthermia was given twice per week and chemotherapy once per week, with the whole treatment lasting for 2-4 weeks. The commonly used drugs were DDP, MMC, 5-FU and so on. Results: Local pain was relieved in 8 of 9 patients, complete disappearance of ascites in 10 of 14. The common side-effects were fat necrosis (14.3%) and abdominal pain (24.8%). Conclusions: Intraperitoneal chemo-hyperthermia with SR-1000 RF appears to be a promising new approach for patients with recurrent or metastatic peritoneo-pelvic malignant tumors, especially for those who did not response to systemic chemotherapy or whose tumor recurred after chemotherapy. As to bulky lesions, local supplementary radiotherapy should be given in order to obtain better local control

  20. Neuronal Rat Brain Damage Caused by Endogenous and Exogenous Hyperthermia

    Directory of Open Access Journals (Sweden)

    Mustafa Aydın

    2012-03-01

    Full Text Available OBJECTIVE: Hyperthermia may induce pathologic alterations within body systems and organs including brain. In this study, neuronal effects of endogenous and exogenous hyperthermia (41°C were studied in rats. METHODS: The endogenous hyperthermia (41°C was induced by lipopolysaccharide and the exogenous by an (electric heater. Possible neuronal damage was evaluated by examining healthy, apoptotic and necrotic cells, and heat shock proteins (HSP 27, HSP 70 in the cerebral cortex, cerebellum and hypothalamus RESULTS: At cellular level, when all neuronal tissues are taken into account; (i a significant increase in the necrotic cells was observed in the both groups (p0.05. CONCLUSION: The neural tissue of brain can show different degree of response to hyperthermia. But we can conclude that endogenous hyperthermia is more harmful to central nervous system than exogenous hyperthermia

  1. Effects of intraoperative irradiation (IORT) and intraoperative hyperthermia (IOHT) on canine sciatic nerve: histopathological and morphometric studies

    International Nuclear Information System (INIS)

    Vujaskovic, Zeljko; Powers, Barbara E.; Paardekoper, Gabriel; Gillette, Sharon M.; Gillette, Edward L.; Colacchio, Thomas A.

    1999-01-01

    Purpose/Objective: Peripheral neuropathies have emerged as the major dose-limiting complication reported after intraoperative radiation therapy (IORT). The combination of IORT with hyperthermia may further increase the risk of peripheral nerve injury. The objective of this study was to evaluate histopathological and histomorphometric changes in the sciatic nerve of dogs, after IORT with or without hyperthermia treatment. Methods and Materials: Young adult beagle dogs were randomized into five groups of 3-5 dogs each to receive IORT doses of 16, 20, 24, 28, or 32 Gy. Six groups of 4-5 dogs each received IORT doses of 12, 16, 20, 24, or 28 Gy simultaneously with 44 deg. C of intraoperative hyperthermia (IOHT) for 60 min. One group of dogs acted as hyperthermia-alone controls. Two years after the treatment, dogs were euthanized, and histopathological and morphometric analyses were performed. Results: Qualitative histological analysis showed prominant changes such as focal necrosis, mineralization, fibrosis, and severe fiber loss in dogs which received combined treatment. Histomorphometric results showed a significantly higher decrease in axon and myelin and small blood vessels, with a corresponding increase in connective tissue in dogs receiving IORT plus hyperthermia treatment. The effective dose for 50% of nerve fiber loss (ED 50 ) in dogs exposed to IORT only was 25.3 Gy. The ED 50 for nerve fiber loss in dogs exposed to IORT combined with IOHT was 14.8 Gy. The thermal enhancement ratio (TER) was 1.7. Conclusion: The probability of developing peripheral neuropathies in a large animal model is higher when IORT is combined with IOHT, when compared to IORT application alone. To minimize the risk of peripheral neuropathy, clinical treatment protocols for the combination of IORT and hyperthermia should not assume a thermal enhancement ratio (TER) to be lower than 1.5

  2. A Reconstruction Method for the Estimation of Temperatures of Multiple Sources Applied for Nanoparticle-Mediated Hyperthermia

    Directory of Open Access Journals (Sweden)

    Idan Steinberg

    2018-03-01

    Full Text Available Solid malignant tumors are one of the leading causes of death worldwide. Many times complete removal is not possible and alternative methods such as focused hyperthermia are used. Precise control of the hyperthermia process is imperative for the successful application of such treatment. To that end, this research presents a fast method that enables the estimation of deep tissue heat distribution by capturing and processing the transient temperature at the boundary based on a bio-heat transfer model. The theoretical model is rigorously developed and thoroughly validated by a series of experiments. A 10-fold improvement is demonstrated in resolution and visibility on tissue mimicking phantoms. The inverse problem is demonstrated as well with a successful application of the model for imaging deep-tissue embedded heat sources. Thereby, allowing the physician then ability to dynamically evaluate the hyperthermia treatment efficiency in real time.

  3. A Reconstruction Method for the Estimation of Temperatures of Multiple Sources Applied for Nanoparticle-Mediated Hyperthermia.

    Science.gov (United States)

    Steinberg, Idan; Tamir, Gil; Gannot, Israel

    2018-03-16

    Solid malignant tumors are one of the leading causes of death worldwide. Many times complete removal is not possible and alternative methods such as focused hyperthermia are used. Precise control of the hyperthermia process is imperative for the successful application of such treatment. To that end, this research presents a fast method that enables the estimation of deep tissue heat distribution by capturing and processing the transient temperature at the boundary based on a bio-heat transfer model. The theoretical model is rigorously developed and thoroughly validated by a series of experiments. A 10-fold improvement is demonstrated in resolution and visibility on tissue mimicking phantoms. The inverse problem is demonstrated as well with a successful application of the model for imaging deep-tissue embedded heat sources. Thereby, allowing the physician then ability to dynamically evaluate the hyperthermia treatment efficiency in real time.

  4. Combined transperineal radiofrequency (RF) interstitial hyperthermia and brachytherapy for localized prostate cancer (PC)

    International Nuclear Information System (INIS)

    Urakami, Shinji; Gonda, Nobuko; Kikuno, Nobuyuki

    2001-01-01

    Hyperthermia has been used effectively as a radiation sensitizer. Interstitial hyperthermoradiotherapy has been therefore utilized as a minimal invasive therapy in attempts to improve local tumor control for various cancers, but not for urological cancer. The purpose of this study was to investigate the safety and feasibility of transperineal hyperthermoradiotherapy for localized PC. Based on our basic study of hyperthermoradiotherapy, we devised the procedure of combined transperineal RF interstitial hyperthermia and brachytherapy for localized prostate cancer. Two patients with localized PC underwent transperineal RF interstitial hyperthermia combined with brachytherapy operation the 192-Ir remote after-loading system (RALS). Under transrectal ultrasound guidance, a total number of 12-18 stainless steel needles for 192-Ir RALS were implanted into the prostatic gland and seminal vesicles (SV) in an optimized pattern. Eight of the needles were used as electrodes for hyperthermia, and were electrically insultated using the vinyl catheter along the length of the subdermal fatty tissue to protect from overheating. Three other needles were utilized for continuous temperature mapping in the prostate. Rectal temperature was also monitored. Total radiation doses of 70 Gy to the prostate and SV were planned as a combination of brachytherapy (24 Gy/4 fraction) and external irradiation using a four-field box technique (46 Gy/23 fraction). Hyperthermic treatment (goal of 42 to 43 deg C for 60 minutes) was performed twice following the 1st and 4th brachytherapy at an interval of more than 48 hours for the recovery of cancer cells from thermotolerance. Both patients reached the treatment goal of all intraprostatic temperatures >43.0 deg C, which was considered favorable for hyperthermia, and the rectal temperatures of both patients remained <38 deg C during hyperthermia. In serial PSA measurements of both patients, serum PSA was less than 1.0 ng/ml within 3 months and has since

  5. Cellular radiation effects and hyperthermia: Cytokinetic investigations with stationary phase yeast cells

    International Nuclear Information System (INIS)

    Fingerhut, R.; Otto, F.; Oldiges, H.; Kiefer, J.

    1980-01-01

    Wild type diploid yeast, Saccharomyces cerevisiae strain 211, was subjected to 250 kV X-rays or 50 0 C heat treatment for 30 min or to a combination of both. X-ray exposure took place either in air or in nitrogen. Cell number, percentage of budding cells and cell cycle progression was followed for up to 12 h post irradiation. The distribution of cell cycle stages was determined by flow cytofluorometry. All treatments cause a retardation of cell division rate. Hyperthermia leads mainly to a lengthening of G 1 , whereas X-rays arrest the cells reversibly in G 2 . The effect of the combined treatment appears to be merely additive. No selective action of hyperthermia on hypoxic cells was found. (orig.) [de

  6. Depression of DNA synthesis rate following hyperthermia, gamma irradiation, cyclotron neutrons and mixed modalities

    International Nuclear Information System (INIS)

    Weber, H.J.; Muehlensiepen, H.; Porschen, W.; Feinendegen, L.E.; Dietzel, F.

    1978-01-01

    The incorporation of the thymidine analogue I-UdR is proportional to the activity of DNA synthesis. The maximum depression of 125-I-UdR incorporation occurs approximately 4 hours after all kinds of treatment. The increase which follow reflects cell processes like reoxygeneration, recovery, recycling and recruitment (although a direct relation is not yet demonstrable). The degree of depression 4 hours after treatment and the time required needs to reach control level is dependent on dose and radiation quaility but no such dependence could be clearly seen for the times of hyperthermia treatment we used. Neutron irradiation and the combination gamma irradiation + hyperthermia show a higher depression and a slower return to normal than gamma irradiation at the same dose. (orig.) [de

  7. Interaction of hyperthermia and radiation: radiation quality

    International Nuclear Information System (INIS)

    Loshek, D.D.; Orr, J.S.; Solomonidis, E.

    1981-01-01

    Cell-survival data were collected to determine the survival response of asynchronous CHO cells subject to radiation and hyperthermia. The irradiation was at room temperature 100 minutes before exposure to hyperthermia at 42 0 C. The survival response to the combination of these two agents is expressed by means of a survival surface, a three-dimensional concept relating cell survival to heat dose and radiation dose. The survival surface could be approximately described by a survival model comprising three components of cell killing: the unperturbed radiation component, the unperturbed hyperthermia component and the interaction component. The dependence of the radiation component and the interaction component on radiation quality were investigated by irradiating with either 60 Co γ rays, 250 kV X rays or 14.7 MeV neutrons. An analysis suggests that the interaction component and the radiation component exhibit similar dependencies on radiation quality both for the deposition of damage and the repair or accumulation of that damage. (U.K.)

  8. Eight-MHz RF-hyperthermia for advanced urological malignancies

    International Nuclear Information System (INIS)

    Hisazumi, Haruo; Nakajima, Kazuyoshi

    1986-01-01

    Eight-MHz radiofrequency hyperthermia (H) using a Thermotron-RF Model 8, and its combination with irradiation (RH), anticancer drugs (CH) or anticancer drugs plus irradiation (CRH), were carried out for a total of 48 urological malignancies: 10 cases of renal cancer, 1 of renal pelvic cancer, 2 of uretetral cancer, 19 of bladder cancer, 5 of prostatic cancer, 9 of metastatic lesion of urological cancers and 2 of other urological cancers. All had failed in previous treatments, or had not undergone surgery because of their poor general condition. Four cases, including 2 of bladder cancer, 1 of prostatic cancer and 1 of metastatic lesion of bladder cancer, were treated with H. Twenty-five cases, including 3 renal cancer cases, were treated with RH. Seven of the 10 cases of renal cancer were treated with mitomycin C-microcapsule embolization prior to RH (CRH). Twelve of the 23 cases with urothelial cancer or its metastasis, including 1 of renal pelvic cancer, 10 of bladder cancer and 1 of metastatic lesion of bladder cancer, received combined treatment of THP-adriamycin, one of the derivatives of adriamycin, by i.v. and RF-heating (CH). Hyperthermia was given twice a week, totalling 10 sessions in 5 weeks. Intratumoral temperature was kept above 42.5 deg C for 30 to 40 minutes during one-hour heating. Complete tumor disappearance was obtained in the 5 bladder cancer cases. Partial tumor regression, defined as a regression of 50 % or more, was obtained in 11 cases. As side effects, mild skin burns and anorexia were observed in approximately 30 to 40 % of cases. Seven obese cases, who had subcutaneous tissue 15 mm thick or more, developed fat tissue induration after treatment. (author)

  9. A theoretical study of cylindrical ultrasound transducers for intracavitary hyperthermia

    International Nuclear Information System (INIS)

    Lin, W.-L.; Fan, W.-C.; Yen, J.-Y.; Chen, Y.-Y.; Shieh, M.-J.

    2000-01-01

    Purpose: The purpose of this paper was to examine the heating patterns and penetration depth when a cylindrical ultrasound transducer is employed for intracavitary hyperthermia treatments. Methods and Materials: The present study employs a simulation program based on a simplified power deposition model for infinitely long cylindrical ultrasound transducers. The ultrasound power in the tissue is assumed to be exponentially attenuated according to the penetration depth of the ultrasound beam, and a uniform attenuation for the entire treatment region is also assumed. The distribution of specific absorption rate (SAR) ratio (the ratio of SAR for a point within the tissue to that for a specific point on the cavity surface) is used to determine the heating pattern for a set of given parameters. The parameters considered are the ultrasound attenuation in the tissue, the cavity size, and the transducer eccentricity. Results: Simulation results show that the ultrasound attenuation in the tissue, the cavity size, and the transducer eccentricity are the most influential parameters for the distribution of SAR ratio. A low frequency transducer located in a large cavity can produce a much better penetration. The cavity size is the major parameter affecting the penetration depth for a small cavity size, such as interstitial hyperthermia. The heating pattern can also be dramatically changed by the transducer eccentricity and radiating sector. In addition, for a finite length of cylindrical transducer, lower SAR ratio appears in the regions near the applicator's edges. Conclusion: The distribution of SAR ratio indicates the relationship between the treatable region and the parameters if an appropriate threshold of SAR ratio is taken. The findings of the present study comprehend whether or not a tumor is treatable, as well as select the optimal driving frequency, the appropriate cavity size, and the eccentricity of a cylindrical transducer for a specific treatment

  10. The effect of hyperthermia and radiation on lysosomal enzyme activity of mouse mammary tumours

    International Nuclear Information System (INIS)

    Barratt, G.M.; Wills, E.D.

    1979-01-01

    The effects of hyperthermia and radiation have been studied on the acid phosphatase and β-glucuronidase activities in lysosomes of C3H mice mammary tumours and of the spleen. Quantitative histochemical methods have been used. Hyperthermic treatment of both spontaneous and transplanted tumours caused an increase in the activity of both acid phosphatase and β-glucuronase when measured immediately after treatment, but the activities returned to normal after 24 hours. In contrast a radiation dose of 3500 rad did not cause an increase in activity of either enzyme immediately, but a large activation was observed after 24 hr. Combination of hyperthermic and radiation treatment caused increases in enzyme activities which were dependent on the time after treatment. Hyperthermic treatment of the lower body of mice bearing tumours also caused activation of lysosomal enzymes in the spleen. This may be hormone mediated. It is considered that the increased lysosomal enzyme activity observed after hyperthermia may be a consequence of increased permeability of the lysosomal membrane caused by hyperthermia. (author)

  11. Magnetic hyperthermia dosimetry by biomechanical properties revealed in magnetomotive optical coherence elastography (MM-OCE) (Conference Presentation)

    Science.gov (United States)

    Huang, Pin-Chieh; Marjanovic, Marina; Spillman, Darold R.; Odintsov, Boris M.; Boppart, Stephen A.

    2016-03-01

    Magnetic nanoparticles (MNPs) have been utilized in magnetic hyperthermia to treat solid tumors. Under an appropriate AC magnetic field, energy can be transferred to the MNPs to heat up the intended tissue target while sparing non-targeted healthy tissue. However, a sensitive monitoring technique for the dose of MNP thermal therapy is desirable in order to prevent over-treatment and collateral injury. Typical hyperthermia dosimetry often relies on changes in imaging properties or temperature measurements based on the thermal distribution. Alternative dosimetric indicators can include the biomechanical properties of the tissue, reflecting the changes due to protein denaturation, coagulation, and tissue dehydration during hyperthermia treatments. Tissue stiffness can be probed by elastography modalities including MRI, ultrasound imaging, and optical coherence elastography (OCE), with OCE showing the highest displacement sensitivity (tens of nanometers). Magnetomotive optical coherence elastography (MM-OCE) is one type of OCE that utilizes MNPs as internal force transducers to probe the tissue stiffness. Therefore, we examined the feasibility of evaluating the hyperthermia dose based on the elasticity changes revealed by MM-OCE. Superparamagnetic MNPs were applied to ex vivo tissue specimens for both magnetic hyperthermia and MM-OCE experiments, where temperature and elastic modulus were obtained. A correlation between temperature rise and measured stiffness was observed. In addition, we found that with repetitive sequential treatments, tissue stiffness increased, while temperature rise remained relatively constant. These results potentially suggest that MM-OCE could indicate the irreversible changes the tissue undergoes during thermal therapy, which supports the idea for MM-OCE-based hyperthermia dosage control in future applications.

  12. Hyperthermia system working in combination with an MR imaging unit

    International Nuclear Information System (INIS)

    LeBihan, D.J.; Delannoy, J.; Levin, R.L.; Hoult, D.I.

    1988-01-01

    The authors propose a hyperthermia device to be used for temperature monitoring. It consists of a modified miniannular phased array (MAPA) radio-frequency applicator designed for limb tumor treatment that works in combination with a whole-body MR imaging unit operating at 21 MHz. Highly accurate (0.5 0 c/0.8 cm 2 ) temperature images are obtained noninvasively throughout the heated volume from MR images of molecular diffusion, the relation of which with temperature is well known. The MAPA, electrically modified to be compatible with MR imagers, can be centered inside the MR head coil. The combined system was tested on a phantom in which the temperature distribution was confirmed by miniature thermocouples

  13. Thermometry of hot spot using NMR for hyperthermia

    International Nuclear Information System (INIS)

    Amemiya, Yoshifumi; Kamimura, Yoshitsugu

    1983-01-01

    Lately noticed hyperthermia in cancer therapy requires non-invasive measurement of the temperature at the warmed site in the deep portion of human body. Nuclear magnetic relaxation time of NMR is also usable for cancer diagnosis. For coordination of these two techniques, it was judged suitable to measure temperature by NMR so that cancer diagnosis and treatment and evaluation of therapeutic effect might be incorporated into one system. This report dealt with concrete procedures of measuring the temperature of deep portions by NMR. Computations revealed that the coefficient of temperature of the thermal equilibrium magnetization was useful, that magnetic field focusing was the most effective imaging technique and that temperature rise in areas about 2 cm in radius could be measured without large errors. (Chiba, N.)

  14. Transient mild hyperthermia induces E-selectin mediated localization of mesoporous silicon vectors in solid tumors.

    Directory of Open Access Journals (Sweden)

    Dickson K Kirui

    Full Text Available BACKGROUND: Hyperthermia treatment has been explored as a strategy to overcome biological barriers that hinder effective drug delivery in solid tumors. Most studies have used mild hyperthermia treatment (MHT to target the delivery of thermo-sensitive liposomes carriers. Others have studied its application to permeabilize tumor vessels and improve tumor interstitial transport. However, the role of MHT in altering tumor vessel interfacial and adhesion properties and its relationship to improved delivery has not been established. In the present study, we evaluated effects of MHT treatment on tumor vessel flow dynamics and expression of adhesion molecules and assessed enhancement in particle localization using mesoporous silicon vectors (MSVs. We also determined the optimal time window at which maximal accumulation occur. RESULTS: In this study, using intravital microscopy analyses, we showed that temporal mild hyperthermia (∼1 W/cm(2 amplified delivery and accumulation of MSVs in orthotopic breast cancer tumors. The number of discoidal MSVs (1000×400 nm adhering to tumor vasculature increased 6-fold for SUM159 tumors and 3-fold for MCF-7 breast cancer tumors. By flow chamber experiments and Western blotting, we established that a temporal increase in E-selectin expression correlated with enhanced particle accumulation. Furthermore, MHT treatment was shown to increase tumor perfusion in a time-dependent fashion. CONCLUSIONS: Our findings reveal that well-timed mild hyperthermia treatment can transiently elevate tumor transport and alter vascular adhesion properties and thereby provides a means to enhance tumor localization of non-thermally sensitive particles such as MSVs. Such enhancement in accumulation could be leveraged to increase therapeutic efficacy and reduce drug dosing in cancer therapy.

  15. Radionuclide investigations of the hormonal reflection of warm stress in cancer patients under whole body guided hyperthermia

    International Nuclear Information System (INIS)

    Prokhorova, V.I.; Zhavrid, Eh.A.; Fradkin, S.Z.; Tsyrus', T.P.; Shitikov, B.D.; Kosheleva, M.I.

    1991-01-01

    The results of the radioimmunoassay of ACTH, ST, hydrocortisone, glucagon, C-peptide, insulin and cyclic nucleotides in 180 patients with advanced and metastatic melanomas, soft tissue sarcomas, lung cancers and renal cell carcinomas testify to the development of the syndrome of endocrine hyperfunction in patients under whole-body guided hyperthermia and artificial hyperglycemia as well as of functional pancreas insufficiency. The data presented form a biochemical basis for working out measures to optimally carry out whole-body hyperthermia and artificial hyperglycemia treatment, aimed at increasing the range of indications for its use in clinical oncology

  16. Inhibition by hyperthermia of repair synthesis and chromatin reassembly of ultraviolet-induced damage to DNA

    International Nuclear Information System (INIS)

    Bodell, W.J.; Cleaver, J.E.; Roti Roti, J.L.

    1984-01-01

    The authors have investigated the effects of hyperthermia treatment on sequential steps of the repair of UV-induced DNA damage in HeLa cells. DNA repair synthesis was inhibited by 40% after 15 min of hyperthermia treatment at 45 0 C; greater inhibition of repair synthesis occurred with prolonged incubation at 45 0 C. Enzymatic digestion of repair-labeled DNA with Exonuclease III indicated that once DNA repair was initiated, the DNA repair patch was synthesized to completion and that ligation of the DNA repair patch occurred. Thus, the observed inhibition of UV-induced DNA repair synthesis by hyperthermia treatment may be the result of inhibition of enzymes involved in the initiating steps(s) of DNA repair. DNA repair patches synthesized in UV-irradiated cells labeled at 37 0 C with[ 3 H]Thd were 2.2-fold more sensitive to micrococcal nuclease digestion than was parental DNA; if the length of the labeling period was prolonged, the nuclease sensitivity of the repair patch synthesized approached that of the parental DNA. DNA repair patches synthesized at 45 0 C, however, remained sensitive to micrococcal nuclease digestion even after long labeling periods, indicating that heat treatment inhibits the reassembly of the DNA repair patch into nucleosomal structures. 23 references, 3 figures, 2 tables

  17. Effects of X-ray irradiation combined with hyperthermia on human bone marrow cells

    International Nuclear Information System (INIS)

    Xie Huaijiang; Niu Rongjiu; Liu Xiaodong; Liu Huanqin

    1996-01-01

    The authors report on the effects of X-ray irradiation combined with hyperthermia on human bone marrow cells (BMC) in vitro. Observation was made on the morphology of treated cells under optic microscope and ultrastructural changes under electron microscope. The change was not obvious at first after treatment i,e, only the vacuolar degeneration was observed in a few cells under the EM. The survival of BMC alone after irradiation decreased with increase of the irradiation dose. The morphological changes included vacuolar degeneration of cells, swelling of mitochondria, and disintegration of nuclear membranes. The survival rate of BMC after irradiation combined with hyperthermia was significantly lower than that after treatment by either of them alone (P<0.01). The morphological changes were as follows: the cell structure was destroyed, the cell support system and cell organelles were destroyed, the cell membrane and nuclear membranes were destroyed, and the cell plasma and nuclear sap overflowed

  18. Nano-magnetite coated with gold: alternative oncological therapy with magnetic hyperthermia

    International Nuclear Information System (INIS)

    Cordova F, T.; Jimenez G, O.; Basurto I, G.; Martinez E, J. C.

    2017-10-01

    Localized hyperthermia performed through the use of nanoparticles is one of the most promising procedures for the cancer treatment. In this work, the synthesis of magnetite nanoparticles (Fe 2 O 3 ) was carried out using the thermal decomposition method. Subsequently, these nanoparticles were coated with gold and suspended in aqueous phase. As a result, nanoparticles capable of being heated by the application of an alternating magnetic field or through the use of infrared radiation were obtained. As an additional feature, these nanoparticles are biocompatible thanks to their golden coating. The synthesized nanoparticles can be functionalized by the conjugation of a molecule (aptamer, antibody, peptide, etc.) whose target is a cancer cell in order to adhere to it the nanoparticle-marker complex, to subsequently carry out a heating with the objective of induce cell death. In conclusion, the synthesized nanoparticles allow providing an alternative treatment for cancer through the use of localized hyperthermia, either using magnetic or infrared heating. (Author)

  19. Intra-operative placement of catheters for interstitial microwave-induced hyperthermia and iridium brachytherapy

    International Nuclear Information System (INIS)

    Coughlin, C.T.; Wong, T.Z.; Strohbehn, J.W.; Colacchio, T.A.; Belch, R.Z.; Sutton, J.E. Jr.; Douple, E.B.

    1984-01-01

    The authors have previously described a system for delivery of microwave-induced hyperthermia utilizing flexible coaxial cables that are modified to serve as microwave antennas. These small (--1.6mm o.d.) antennas ae introduced into 2mm o.d. nylon catheters implanted in the tumor. This system has been further modified for use in the treatment of surgically unresectible abdominal, pelvic, and head and neck tumors. The modifications are described that were used to treat two pelvic, one upper abdominal, and one base of tongue tumor. The nylon catheters are implanted during surgery. After a short recovery period, the microwave antennas are inserted and the tumor region is heated for --1hr. The antennas are removed, iridium-192 seeds are placed in the catheters, 2800 - 5000 rad (CGy) doses are delivered, followed by a 1hr hyperthermia treatment. The temperature distributions and future applications are discussed

  20. A Case of Fatal Malignant Hyperthermia During Pes Equinovarus Surgery in a Child

    Directory of Open Access Journals (Sweden)

    Ümüt Altuğ

    2018-04-01

    Full Text Available Malignant hyperthermia (MH is a genetic syndrome characterized by hyperthermia, tachycardia, acidosis, and muscle rigidity, often triggered by depolarizing muscle relaxants such as volatile anesthetics and/or succinylcholine. MH usually develops following anesthesia induction, but may occur during and after a surgical intervention. A 4.5-year-old boy was admitted to the pediatric intensive care unit considering MH due to persistent fever, tachycardia and end-tidal carbon dioxide elevation which developed during pes equinovarus surgery. In the follow-up, hypercapnia, fever and refractory metabolic acidosis recurred. Despite the administration of dantrolene sodium and supportive treatments, the patient died. This case is presented to remind the possibility of MH which may be fatal in patients receiving general anesthesia and to emphasize the follow-up and treatment of the patients with MH in pediatric intensive care unit.

  1. Cellular radiation effects and hyperthermia cell cycle kinetics of radiation sensitive mutants of saccharomyces cerevisiae after x-irradiation and hyperthermia

    International Nuclear Information System (INIS)

    Fingerhut, R.; Kiefer, J.; Otto, F.

    1983-01-01

    Radiosensitive mutants rad2, rad9, and rad51 of Saccharomyces cerevisiae were X-irradiated with 120 Gy or 60 Gy, heated at 50 0 C for 30 min or treated with a combination of both and incubated in nutrient medium at 30 0 C. Cell number, percentage of budding cells, and cell cycle progression were determined in 45-min intervals. Cell cycle kinetics were investigated by flow cytofluorometry. Hyperthermia leads mainly to a lengthening of G1, whereas X-rays arrest cells of the rad2 and rad9 mutant in G2 and the rad51 - mutant additionaly in a state with DNA contents above G2. Cell division dealy is influenced by oxygen in all strains but to a lesser extent in the rad2 mutant. The effect of the combined treatment appears to be merely additive in the rad2 and rad9 mutant while the rad51 mutant is sensitized to X-irradiation by hyperthermia. No selective action of hyperthermia on hypoxic cells was found. (orig.)

  2. Part-body hyperthermia with a radiofrequency multiantenna applicator under online control in 1,5 T MR-tomograph

    International Nuclear Information System (INIS)

    Wust, P.; Gellermann, J.; Faehling, H.; Wlodarczyk, W.; Felix, R.; Seebass, M.; Turner, P.; Nadobny, J.; Rau, B.; Hildebrandt, B.; Schlag, P.M.; Oppelt, A.

    2004-01-01

    Objective of this study is the integration of a multiantenna applicator for part-body hyperthermia (BSD 2000/3D) in a 1.5 T MR-tomograph (Siemens Magnetom Symphony) in order to perform noninvasive MR monitoring in real time to increase safety and effectiveness of heat treatments. The positioning unit is mechanically coupled to the MR gantry from the back side and the body coil is utilised for imaging. For that purpose, the hyperthermia antenna system (100 MHz, 1.500 W) and the MR receiver(63.9 MHs) have to be decoupled in terms of high frequency (filter) and electromagnetically (emc). The processing of MR data sets is performed in a hyperthermia planning system. A simultaneous operation of radiofrequency hyperthermia and MR system is possible at clinically relevant power levels. MR imaging is used for tumor diagnostics (standard spin echo sequences), for hyperthermia planning (T1-weighted gradient echo sequences in equal- and opposed-phase techniques), and for temperature measurements according to the proton resonance frequency method (PRF method, phase evaluation registration using a gradient echo sequence with long echo time). In 33 patients with advanced pelvic and abdominal tumors we performed 150 heat sessions under MR monitoring. For 70% of these patients a visualisation of temperature sensitive data during treatment was possible. The evaluated difference images represent a superposition of real temperature increase and a (temperature-induced) perfusion elevation. The hybrid approach renders development of part body hyperthermia possible as an MR-controlled intervention in radiology. (orig.) [de

  3. Modeling of various kinds of applicators used for microwave hyperthermia based on the FDTD method

    Energy Technology Data Exchange (ETDEWEB)

    Camart, J.C.; Despretz, D.; Chive, M.; Pribetich, J. [Domaine Scientifique et Univ. de Villeneuve D`Ascq (France). Dept. Hyperfrequencies et Semiconducteurs

    1996-10-01

    This paper presents the modeling using the finite-difference time domain (FDTD) method of interstitial and endocavitary applicators which have been designed and developed for microwave hyperthermia treatments controlled by microwave radiometry. For each kind of applicators, the numerical results are given concerning the reflection coefficient S{sub 11}, the power deposition, and the heating patterns. These results are compared with the measurements performed on phantom models of human tissues and show a good agreement. Possibilities of future developments are discussed.

  4. Water bath hyperthermia is a simple therapy for psoriasis and also stimulates skin tanning in response to sunlight

    Energy Technology Data Exchange (ETDEWEB)

    Boreham, D.R.; Gasmann, H.C.; Mitchel, R.E.J

    1994-07-01

    An eight week trial, involving superficial hyperthermia delivered biweekly via simple water bath immersion, was tested for its ability to clear mild to moderate psoriatic lesions. Seven patients were treated and three cases rapidly improved. In the remaining patients, the treatment frequency was increased to alternate days; two cases improved significantly, one patient showed a partial response, and the fourth had no visible change (this was the only patient taking concurrent drug therapy - etretinate). In addition to resolving psoriatic lesions, water bath hyperthermia also reduced edema (swelling) and relieved pruritus (itching) in all patients, both during the treatment period and for up to several months after lesions had returned. Lesion reappearance occurred within one to three months after the last heat treatment. We retreated one patient and produced a second complete remission. These results indicate that simple repetitive water bath hyperthermia alone is effective in the treatment of psoriatic lesions in heatable locations. An unexpected side effect was enhanced melanin content (tanning) in all areas where hyperthermia treated skin was exposed to sunlight. (author)

  5. Effect of prior hyperthermia on subsequent thermal enhancement of radiation damage in mouse intestine

    International Nuclear Information System (INIS)

    Marigold, J.C.L.; Hume, S.P.

    1982-01-01

    Hyperthermia given in conjunction with X-rays results in a greater level of radiation injury than following X-rays alone, giving a thermal enhancement ratio (TER). The effect of prior hyperthermia ('priming') on TER was studied in the small intestine of mouse by giving 42.0 deg C for 1 hour at various times before the combined heat and X-ray treatments. Radiation damage was assessed by measuring crypt survival 4 days after radiation. TER was reduced when 'priming' hyperthermia was given 24-48 hours before the combined treatments. The reduction in effectiveness of the second heat treatment corresponded to a reduction in hyperthermal temperature of approximately 0.5 deg C, a value similar to that previously reported for induced resistance to heat given alone ('thermotolerance') (Hume and Marigold 1980). However, the time courses for development and decay of the TER response were much longer than those for 'thermotolerance', suggesting that different mechanisms are involved in thermal damage following heat alone and thermal enhancement of radiation damage

  6. Preliminary clinical results of locoregional hyperthermia for primary and secondary bone tumors

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, J.L.; Nagata, Yasushi; Kanamori, Shuichi; Mitsumori, Michihide; Okuno, Yoshishige; Horii, Naotoshi; Nishimura, Yasumasa; Masunaga, Shinitiro; Hiraoka, Masahiro [Kyoto Univ. (Japan). Graduate School of Medicine

    2000-03-01

    Nineteen primary and secondary bone tumors in 16 patients were treated with hyperthermia plus radiotherapy and/or chemotherapy between 1982 and 1997 at Kyoto University Hospital. The thermometric and clinical results were analyzed retrospectively. In 55 of 86 hyperthermia sessions, the intratumor temperature was measured using a thermometer. Of the 19 tumors, 16 (84%) received heat treatment 4-7 times, and 3 (16%) received 1 or 2 treatments of hyperthermia. The mean maximum, mean minimum and average intratumor temperatures were 42.9, 40.4 and 41.6 deg C, respectively, and 12 (67%) reached a tumor maximum temperature above 42.5 deg C. The durations that intratumor points exceeded 42, 41 and 40 deg C were 27, 34 and 38 min, respectively. The local tumor response to treatment was assessed using X-ray computed tomography. The local response rate was 16% and the local pain relief rate was 63%. The 1-year cumulative survival rate was 60%. Our preliminary results indicated that thermoradiotherapy and thermochemotherapy are clinicaly feasible and potentially beneficial in the management of locally advanced bone tumors. (author)

  7. Physical mechanism and modeling of heat generation and transfer in magnetic fluid hyperthermia through Néelian and Brownian relaxation: a review.

    Science.gov (United States)

    Suriyanto; Ng, E Y K; Kumar, S D

    2017-03-23

    Current clinically accepted technologies for cancer treatment still have limitations which lead to the exploration of new therapeutic methods. Since the past few decades, the hyperthermia treatment has attracted the attention of investigators owing to its strong biological rationales in applying hyperthermia as a cancer treatment modality. Advancement of nanotechnology offers a potential new heating method for hyperthermia by using nanoparticles which is termed as magnetic fluid hyperthermia (MFH). In MFH, superparamagnetic nanoparticles dissipate heat through Néelian and Brownian relaxation in the presence of an alternating magnetic field. The heating power of these particles is dependent on particle properties and treatment settings. A number of pre-clinical and clinical trials were performed to test the feasibility of this novel treatment modality. There are still issues yet to be solved for the successful transition of this technology from bench to bedside. These issues include the planning, execution, monitoring and optimization of treatment. The modeling and simulation play crucial roles in solving some of these issues. Thus, this review paper provides a basic understanding of the fundamental and rationales of hyperthermia and recent development in the modeling and simulation applied to depict the heat generation and transfer phenomena in the MFH.

  8. Biodegradable magnesium nanoparticle-enhanced laser hyperthermia therapy

    Directory of Open Access Journals (Sweden)

    Wang Q

    2012-08-01

    Full Text Available Qian Wang,1 Liping Xie,1 Zhizhu He,2 Derui Di,2 Jing Liu1,21Department of Biomedical Engineering, School of Medicine, Tsinghua University, 2Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, People's Republic of ChinaBackground: Recently, nanoparticles have been demonstrated to have tremendous merit in terms of improving the treatment specificity and thermal ablation effect on tumors. However, the potential toxicity and long-term side effects caused by the introduced nanoparticles and by expelling them out of the body following surgery remain a significant challenge. Here, we propose for the first time to directly adopt magnesium nanoparticles as the heating enhancer in laser thermal ablation to avoid these problems by making full use of the perfect biodegradable properties of this specific material.Methods: To better understand the new nano “green” hyperthermia modality, we evaluated the effects of magnesium nanoparticles on the temperature transients inside the human body subject to laser interstitial heating. Further, we experimentally investigated the heating enhancement effects of magnesium nanoparticles on a group of biological samples: oil, egg white, egg yolk, in vitro pig tissues, and the in vivo hind leg of rabbit when subjected to laser irradiation.Results: Both the theoretical simulations and experimental measurements demonstrated that the target tissues injected with magnesium nanoparticles reached much higher temperatures than tissues without magnesium nanoparticles. This revealed the enhancing behavior of the new nanohyperthermia method.Conclusion: Given the unique features of magnesium nanoparticles – their complete biological safety and ability to enhance heating – which most other advanced metal nanoparticles do not possess, the use of magnesium nanoparticles in hyperthermia therapy offers an important “green” nanomedicine modality for treating tumors

  9. Comparison of radiosensitization by 41 deg. C hyperthermia during low dose rate irradiation and during pulsed simulated low dose rate irradiation in human glioma cells

    International Nuclear Information System (INIS)

    Raaphorst, G. Peter; Ng, Cheng E.; Shahine, Bilal

    1999-01-01

    Purpose: Long duration mild hyperthermia has been shown to be an effective radiosensitizer when given concurrently with low dose rate irradiation. Pulsed simulated low dose rate (PSLDR) is now being used clinically, and we have set out to determine whether concurrent mild hyperthermia can be an effective radiosensitizer for the PSLDR protocol. Materials and Methods: Human glioma cells (U-87MG) were grown to plateau phase and treated in plateau phase in order to minimize cell cycle redistribution during protracted treatments. Low dose rate (LDR) irradiation and 41 deg. C hyperthermia were delivered by having a radium irradiator inside a temperature-controlled incubator. PSLDR was given using a 150 kVp X-ray unit and maintaining the cells at 41 deg. C between irradiations. The duration of irradiation and concurrent heating depended on total dose and extended up to 48 h. Results: When 41 deg. C hyperthermia was given currently with LDR or PSLDR, the thermal enhancement ratios (TER) were about the same if the average dose rate for PSLDR was the same as for LDR. At higher average dose rates for PSLDR the TERs became less. Conclusions: Our data show that concurrent mild hyperthermia can be an effective sensitizer for PSLDR. This sensitization can be as effective as for LDR if the same average dose rate is used and the TER increases with decreasing dose rate. Thus mild hyperthermia combined with PSLDR may be an effective clinical protocol

  10. Trial of radiation therapy combined with hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    Takegawa, Y; Fujiwara, K; Oe, J; Nagase, M; Akiyama, H [Tokushima Univ. (Japan). School of Medicine

    1978-08-01

    Nine patients were treated by the combination therapy of external irradiation and hyperthermia, 5 patients with metastatic lesions; two breast cancer, one lung cancer, one malignant melanoma, one vulva cancer, 1 patient with recurrent lesion of skin cancer and 3 patients with bladder cancer. All patients were treated by heating locally (42/sup 0/C, 30 min) followed by external irradiation with 4,000 - 5,000 rad over 4 to 5 weeks. No local recurrence was found in 4 of 9 patients.

  11. Pre-clinical testing of a phased array ultrasound system for MRI-guided noninvasive surgery of the brain--a primate study.

    Science.gov (United States)

    Hynynen, Kullervo; McDannold, Nathan; Clement, Greg; Jolesz, Ferenc A; Zadicario, Eyal; Killiany, Ron; Moore, Tara; Rosen, Douglas

    2006-08-01

    MRI-guided and monitored focused ultrasound thermal surgery of brain through intact skull was tested in three rhesus monkeys. The aim of this study was to determine the amount of skull heating in an animal model with a head shape similar to that of a human. The ultrasound beam was generated by a 512 channel phased array system (Exablate 3000, InSightec, Haifa, Israel) that was integrated within a 1.5-T MR-scanner. The skin was pre-cooled by degassed temperature controlled water circulating between the array surface and the skin. Skull surface temperature was measured with invasive thermocouple probes. The results showed that by applying surface cooling the skin and skull surface can be protected, and that the brain surface temperature becomes the limiting factor. The MRI thermometry was shown to be useful in detecting the tissue temperature distribution next to the bone, and it should be used to monitor the brain surface temperature. The acoustic intensity values during the 20 s sonications were adequate for thermal ablation in the human brain provided that surface cooling is used.

  12. Effect of radiation combined with hyperthermia on human prostatic carcinoma cell lines in culture

    International Nuclear Information System (INIS)

    Kaver, I.; Ware, J.L.; Wilson, J.D.; Koontz, W.W. Jr.

    1991-01-01

    The effect of radiation combined with heat on three human prostatic carcinoma cell lines growing in vitro was investigated. Cells were exposed to different radiation doses followed by heat treatment at 43 degrees C for one hour. Heat treatment, given ten minutes after radiation, significantly enhanced the radiation response of all the cell lines studied. The combined effect of radiation and heat produced greater cytotoxicity than predicted from the additive effects of the two individual treatment modalities alone. These results indicate that a combined treatment regimen of radiation plus hyperthermia (43 degrees, 1 hr) might be an important tool in maintaining a better local control of prostatic cancer

  13. FDTD verification of deep-set brain tumor hyperthermia using a spherical microwave source distribution

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, D. [20th Intelligence Squadron, Offutt AFB, NE (United States); Rappaport, C.M. [Northeastern Univ., Boston, MA (United States). Center for Electromagnetics Research; Terzuoli, A.J. Jr. [Air Force Inst. of Tech., Dayton, OH (United States). Graduate School of Engineering

    1996-10-01

    Although use of noninvasive microwave hyperthermia to treat cancer is problematic in many human body structures, careful selection of the source electric field distribution around the entire surface of the head can generate a tightly focused global power density maximum at the deepest point within the brain. An analytic prediction of the optimum volume field distribution in a layered concentric head model based on summing spherical harmonic modes is derived and presented. This ideal distribution is then verified using a three-dimensional finite difference time domain (TDTD) simulation with a discretized, MRI-based head model excited by the spherical source. The numerical computation gives a very similar dissipated power pattern as the analytic prediction. This study demonstrates that microwave hyperthermia can theoretically be a feasible cancer treatment modality for tumors in the head, providing a well-resolved hot-spot at depth without overheating any other healthy tissue.

  14. Magnetic Hyperthermia and Oxidative Damage to DNA of Human Hepatocarcinoma Cells

    Directory of Open Access Journals (Sweden)

    Filippo Cellai

    2017-04-01

    Full Text Available Nanotechnology is addressing major urgent needs for cancer treatment. We conducted a study to compare the frequency of 3-(2-deoxy-β-d-erythro-pentafuranosylpyrimido[1,2-α]purin-10(3H-one deoxyguanosine (M1dG and 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG adducts, biomarkers of oxidative stress and/or lipid peroxidation, on human hepatocarcinoma HepG2 cells exposed to increasing levels of Fe3O4-nanoparticles (NPs versus untreated cells at different lengths of incubations, and in the presence of increasing exposures to an alternating magnetic field (AMF of 186 kHz using 32P-postlabeling. The levels of oxidative damage tended to increase significantly after ≥24 h of incubations compared to controls. The oxidative DNA damage tended to reach a steady-state after treatment with 60 μg/mL of Fe3O4-NPs. Significant dose–response relationships were observed. A greater adduct production was observed after magnetic hyperthermia, with the highest amounts of oxidative lesions after 40 min exposure to AMF. The effects of magnetic hyperthermia were significantly increased with exposure and incubation times. Most important, the levels of oxidative lesions in AMF exposed NP treated cells were up to 20-fold greater relative to those observed in nonexposed NP treated cells. Generation of oxidative lesions may be a mechanism by which magnetic hyperthermia induces cancer cell death.

  15. Magnetic Hyperthermia and Oxidative Damage to DNA of Human Hepatocarcinoma Cells.

    Science.gov (United States)

    Cellai, Filippo; Munnia, Armelle; Viti, Jessica; Doumett, Saer; Ravagli, Costanza; Ceni, Elisabetta; Mello, Tommaso; Polvani, Simone; Giese, Roger W; Baldi, Giovanni; Galli, Andrea; Peluso, Marco E M

    2017-04-29

    Nanotechnology is addressing major urgent needs for cancer treatment. We conducted a study to compare the frequency of 3-(2-deoxy-β-d-erythro-pentafuranosyl)pyrimido[1,2-α]purin-10(3 H )-one deoxyguanosine (M₁dG) and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) adducts, biomarkers of oxidative stress and/or lipid peroxidation, on human hepatocarcinoma HepG2 cells exposed to increasing levels of Fe₃O₄-nanoparticles (NPs) versus untreated cells at different lengths of incubations, and in the presence of increasing exposures to an alternating magnetic field (AMF) of 186 kHz using 32 P-postlabeling. The levels of oxidative damage tended to increase significantly after ≥24 h of incubations compared to controls. The oxidative DNA damage tended to reach a steady-state after treatment with 60 μg/mL of Fe₃O₄-NPs. Significant dose-response relationships were observed. A greater adduct production was observed after magnetic hyperthermia, with the highest amounts of oxidative lesions after 40 min exposure to AMF. The effects of magnetic hyperthermia were significantly increased with exposure and incubation times. Most important, the levels of oxidative lesions in AMF exposed NP treated cells were up to 20-fold greater relative to those observed in nonexposed NP treated cells. Generation of oxidative lesions may be a mechanism by which magnetic hyperthermia induces cancer cell death.

  16. Modeling of heat transfer in a vascular tissue-like medium during an interstitial hyperthermia process.

    Science.gov (United States)

    Hassanpour, Saeid; Saboonchi, Ahmad

    2016-12-01

    This paper aims to evaluate the role of small vessels in heat transfer mechanisms of a tissue-like medium during local intensive heating processes, for example, an interstitial hyperthermia treatment. To this purpose, a cylindrical tissue with two co- and counter-current vascular networks and a central heat source is introduced. Next, the energy equations of tissue, supply fluid (arterial blood), and return fluid (venous blood) are derived using porous media approach. Then, a 2D computer code is developed to predict the temperature of blood (fluid phase) and tissue (solid phase) by conventional volume averaging method and a more realistic solution method. In latter method, despite the volume averaging the blood of interconnect capillaries is separated from the arterial and venous blood phases. It is found that in addition to blood perfusion rate, the arrangement of vascular network has considerable effects on the pattern and amount of the achieved temperature. In contrast to counter-current network, the co-current network of vessels leads to considerable asymmetric pattern of temperature contours and relocation of heat affected zone along the blood flow direction. However this relocation can be prevented by changing the site of hyperthermia heat source. The results show that the cooling effect of co-current blood vessels during of interstitial heating is more efficient. Despite much anatomical dissimilarities, these findings can be useful in designing of protocols for hyperthermia cancer treatment of living tissue. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Responses to hyperthermia (420, 440) and/or radiation in four mammalian cell lines in vitro

    International Nuclear Information System (INIS)

    Miyakoshi, Junji

    1981-01-01

    Survival in response to hyperthermia at 42 and 44 0 C, both alone and in combination with X-irradiation was examined in vitro in Chinese hamster V-79, HeLa-S3, murine Ehrlich ascites tumor cells (EH) and murine L-fibroblasts. L-cells were markedly thermo- and radiosensitive, while the other three cell lines, although not so sensitive did show similar responses. When each cell line was exposed to split dose Hyperthermia in the 42 → 44 0 C sequence, survival after the second treatment was increased for V-79 and HeLa-S3 cells, but was not significantly changed for EH and L-cells. In the case of split dose exposure in the 44 → 42 0 C sequence, survival after the second treatment was markedly decreased for V-79, EH and HeLa-S3 cells, but only slightly for L-cells. When hyperthermia at 42 or 44 0 C was followed by X-irradiation immediately, V-79, EH and HeLa-S3 cells showed decrements in both D sub(q) and D sub(o) values, while L-cells showed a decrement only in D sub(q) but no significant change in D sub(o). From these results, it seems that the hyperthermic damage by exposure to 44 0 C may be different from that by exposure to 42 0 C. (author)

  18. Membrane defect in procine malignant hyperthermia

    International Nuclear Information System (INIS)

    O'Brien, P.J.

    1985-01-01

    Malignant hyperthermia (MH) has been proposed to result from abnormal calcium-homeostasis in skeletal muscle. This study tested the hypothesis that calcium-sequestration or calcium-release by sarcoplasmic reticulum was abnormal in MH-susceptible swine. A heavy sarcoplasmic reticulum fraction (HSR), enriched in terminal cisternae, was isolated from MH and control muscle using differential and density-gradient centrifugation. Calcium transport was studied using 45 Ca radioisotope and Millipore filtration. Enzymatic activities, cholesterol, phospholipid, and protein composition were determined using spectrophotometric techniques and polyacrylamide gel electrophoresis. Properties of calcium-sequestration by MH and control HSR were indistinguishable, although Ca 2+ -ATPase and calsequestrin content were 100% increased in MH HSR. However when muscle homogenate pH was decreased due to MH, calcium-uptake activity was depressed to <5% of control values. Results of this study indicate a model for the etiopathogenesis of MH, and for the inheritance and diagnosis of susceptibility to MH. Malignant hyperthermia is initiated due to a hypersensitive HSR calcium-release mechanism and propagated by a loss of calcium-sequestering function as acidosis develops. Susceptibility is inherited in an autosomal, codominant pattern and may be diagnosed most definitively and sensitively on the basis of calcium-release sensitivity-tests, performed on isolated HSR

  19. Long duration mild temperature hyperthermia and brachytherapy.

    Science.gov (United States)

    Armour, E P; Raaphorst, G P

    2004-03-01

    Combining long duration mild temperature hyperthermia (LDMH) and low dose-rate (LDR) brachytherapy to enhance therapeutic killing of cancer cells was proposed many years ago. The cellular and tumour research that supports this hypothesis is presented in this review. Research describing LDMH interaction with pulsed brachytherapy and high dose-rate brachytherapy using clinically relevant parameters are compared with LDMH/LDR brachytherapy. The mechanism by which LDMH sensitizes LDR has been established as the inhibition of sublethal damage repair. The molecular mechanisms have been shown to involve DNA repair enzymes, but the exact nature of these processes is still under investigation. The relative differences between LDMH interactions with human and rodent cells are presented to help in the understanding of possible roles of LDMH in clinical application. The role of LDMH in modifying tumour blood flow and its possible role in LDR sensitization of tumours is also presented. The positive aspects of LDMH-brachytherapy for clinical application are sixfold; (1) the thermal goals (temperature, time and volume) are achievable with currently available technology, (2) the hyperthermia by itself has no detectable toxic effects, (3) thermotolerance appears to play a minor if any role in radiation sensitization, (4) TER of around 2 can be expected, (5) hypoxic fraction may be decreased due to blood flow modification and (6) simultaneous chemotherapy may also be sensitized. Combined LDMH and brachytherapy is a cancer therapy that has established biological rationale and sufficient technical and clinical advancements to be appropriately applied. This modality is ripe for clinical testing.

  20. Hyperthermia effects in the presence of gold nanoparticles together with chemotherapy on Saos-2 cell line

    International Nuclear Information System (INIS)

    Sazgarnia, A.; Bahreyni Toosi, M. H.; Haji Ghahremani, F.; Rajabi, O.; Aledavood, A.; Esmaily, H.

    2011-01-01

    Hyperthermia created by microwave, infrared, ultrasound and other methods, is often utilized as an adjuvant to sensitize cancer cells to the effects of chemotherapy and radiation therapy. We investigated the efficacy of hyperthermia using microwave in synergy with chemotherapy in the presence and absence and gold nanoparticles. Material and Methods: After culturing and proliferation of the Saos-2 cell line derived from human osteogenic sarcoma, the cells were incubated at two concentrations of gold nanoparticles in two diameters of 20 and 40 nm and in the absence and presence of doxorubicin in different groups. Forty eight hours after irradiating the cells with microwave up to a temperature of 42 d egree C , cell survival rate was determined using the MTT method, in order to study the effectiveness of the therapeutic parameters. Results: Cell survival in the presence of gold nanoparticles was greater than 95%. After chemotherapy by doxorubicin with and without 40 nm gold nanoparticles, cell survival rates were determined as 62.8% and 37.1 %, declining down to 17% and 4.1% respectively following the combined treatment with microwave and chemotherapy in the presence of 20 and 40 nm gold nanoparticles. Discussion and Conclusions: Gold nanoparticles did not induce any cytotoxicity by themselves; their presence along with microwave provided a reduction in survival rate that was comparable in severity with the lethal effects of doxorubicin. microwave hyperthermia with gold nanoparticles produced a higher treatment efficiency in comparison to similar groups in which gold nanoparticles were absent. The synergism observed between hyperthermia and chemotherapy was dependent in gold nanoparticles' size and concentration. This finding could be caused by increased uptake of doxorubicin by the cells in the presence of gold nanoparticles.

  1. Photoacoustic-Based-Close-Loop Temperature Control for Nanoparticle Hyperthermia.

    Science.gov (United States)

    Xiaohua, Feng; Fei, Gao; Yuanjin, Zheng

    2015-07-01

    Hyperthermia therapy requires tight temperature control to achieve selective killing of cancerous tissue with minimal damage on surrounding healthy tissues. To this end, accurate temperature monitoring and subsequent heating control are critical. However, an economic, portable, and real-time temperature control solution is currently lacking. To bridge this gap, we present a novel portable close-loop system for hyperthermia temperature control, in which photoacoustic technique is proposed for noninvasive real-time temperature measurement. Exploiting the high sensitivity of photoacoustics, the temperature is monitored with an accuracy of around 0.18 °C and then fed back to a controller implemented on field programmable gate array (FPGA) for temperature control. Dubbed as portable hyperthermia feedback controller (pHFC), it stabilizes the temperature at preset values by regulating the hyperthermia power with a proportional-integral-derivative (PID) algorithm; and to facilitate digital implementation, the pHFC further converts the PID output into switching values (0 and 1) with the pulse width modulation (PWM) algorithm. Proof-of-concept hyperthermia experiments demonstrate that the pHFC system is able to bring the temperature from baseline to predetermined value with an accuracy of 0.3° and a negligible temperature overshoot. The pHFC can potentially be translated to clinical applications with customized hyperthermia system design. This paper can facilitate future efforts in seamless integration of close-loop temperature control solution and various clinical hyperthermia systems.

  2. A seven-year disease-free survivor of malignant pleural mesothelioma treated with hyperthermia and chemotherapy: a case report

    Directory of Open Access Journals (Sweden)

    Okonogi Noriyuki

    2012-12-01

    Full Text Available Abstract Introduction Malignant pleural mesothelioma was once a rare finding but its incidence is increasing worldwide, most likely because of widespread exposure to asbestos. Although complete surgical resection is considered the only curative treatment, the results of surgery have shown a median survival time of only one year. In inoperable cases, chemotherapy, radiotherapy, and a combination of both have been considered as palliative therapy. Therefore, outcomes for inoperable cases have been poor. Here, we report the case of a long-term survivor treated with hyperthermia and chemotherapy. Case presentation A 61-year-old Japanese man with a performance status of 1 due to chest pain was referred to our hospital. He had a history of asbestos exposure for approximately five years. A computed tomography scan showed diffuse extensive right pleural thickening with small nodular lesions, and video-assisted thoracoscopy revealed tumor invasion of the ipsilateral chest wall muscles. The histopathologic findings were consistent with a diagnosis of malignant pleural mesothelioma (sarcomatoid type. The tumor was diagnosed as being stage cT3N0M0. Our patient refused any invasive therapies including surgery and radiotherapy, and was therefore treated with hyperthermia and systemic chemotherapy with agents such as cisplatin and irinotecan. He underwent three hyperthermia sessions and a single course of chemotherapy without any severe complications. One month after treatment, a follow-up computed tomography scan showed no definitive abnormality in the thoracic space. Our patient has subsequently survived without any evident disease for more than seven years. Conclusions The combination of hyperthermia and chemotherapy may be a novel and safe therapeutic option for malignant pleural mesothelioma, and can be considered for patients ineligible for radical treatment. Further clinical studies of the combination of hyperthermia and chemotherapy are needed to

  3. Reirradiation + hyperthermia for recurrent breast cancer en cuirasse

    Energy Technology Data Exchange (ETDEWEB)

    Oldenborg, Sabine; Rasch, Coen R.N.; Os, Rob van; Kusumanto, Yoka H.; Voerde Sive Voerding, Paul J. zum; Crezee, Hans; Tienhoven, Geertjan van [University of Amsterdam (AMC), Department of Radiation Oncology, Z1-215, Academic Medical Center, Amsterdam (Netherlands); Oei, Bing S.; Venselaar, Jack L. [Institute Verbeeten (BVI), Department of Radiation Oncology, Tilburg (Netherlands); Heymans, Martijn W. [VU University Medical Center, Department of Epidemiology and Biostatistics, Amsterdam (Netherlands)

    2018-03-15

    Patients with irresectable locoregional recurrent breast cancer en cuirasse (BCEC) do not have effective curative treatment options. Hyperthermia, the elevation of tumor temperature to 40-45 C, is a well-established radio- and chemotherapy sensitizer. A total of 196 patients were treated with reirradiation and hyperthermia (reRT+HT) at two Dutch institutes from 1982-2005. The palliative effect was evaluated in terms of clinical outcome and toxicity. All patients received previous irradiation to a median dose of 50 Gy. In all, 75% of patients received 1-6 treatment modalities for previous tumor recurrences. ReRT consisted of 8 x 4 Gy given twice a week or 12 x 3 Gy given four times a week. Superficial hyperthermia was added once or twice a week. Tumor area comprised ≥1/2 of the ipsilateral chest wall. Overall clinical response rate was 72% (complete response [CR] 30%, partial response [PR] 42%, stable disease [SD] 22%, progressive disease [PD] 6%). The local progression-free rate at 1 year was 24%. Median survival was 6.9 months. Forty-three percent of our patients with CR, PR, SD after treatment remained infield progression-free until death or last follow-up. Acute ≥grade 3 toxicity occurred in 33% of patients, while late ≥grade 3 toxicity was recorded in 14% of patients. Tumor ulceration prior to treatment had a negative impact on both clinical outcome and toxicity. ReRT+HT provides sustainable palliative tumor control, despite refractory, extensive tumor growth. Compared to currently available systemic treatment options, reRT+HT is more effective with less toxicity. (orig.) [German] Fuer Patienten mit inoperablen lokoregionalen Rueckfaellen von Brustkrebs in Form eines Cancer en cuirasse (BCEC) gibt es keine effektiven kurativen Behandlungsoptionen. Die Hyperthermie, bei der die Tumortemperatur auf 40-45 C erhoeht wird, ist eine etablierte Methode zur Radio- und Chemotherapiesensibilisierung. Insgesamt 161 Patientinnen wurden in zwei niederlaendischen

  4. A JASTRO study group report. A randomized phase III trial of hyperthermia in combination with radiotherapy for superficial tumors

    International Nuclear Information System (INIS)

    Hiraoka, Masahiro; Nishimura, Yasumasa; Mitsumori, Michihide

    1998-01-01

    Result of study about local effect of hyperthermia in combination with radiotherapy for superficial tumors was reported. The irradiation was more than 90% isodose for lesion, and total dose was 60 Gy in cases with anamnesis and 40-50 Gy and without anamnesis at a rate of five times a week and 2 Gy at one time. Hyperthermia was carried out four times; once a week, at 42.5 degrees on tumor side edge, and for 40 minutes. Total 53 cases (neck lymph node metastasis 30 cases, relapse breast cancer 11, advanced breast cancer 1, other superficial tumor 11) were divided into 2 groups. Radiotherapy without hyperthermia (group R) was 27 cases, radiotherapy with hyperthermia (group H) was 26 cases. CR and CR+PR within 2 months after treatment were as follows: Group R: 50%, 85%, Group H: 64%, 100%. The CR+PR was superior in group H (p=0.0497). The CR at maximum effect after treatment was 65% of group R and 86% of group H (p=0.17). The local control rate after CR was not different in both groups. (K.H.)

  5. A Parallel 2D Numerical Simulation of Tumor Cells Necrosis by Local Hyperthermia

    International Nuclear Information System (INIS)

    Reis, R F; Loureiro, F S; Lobosco, M

    2014-01-01

    Hyperthermia has been widely used in cancer treatment to destroy tumors. The main idea of the hyperthermia is to heat a specific region like a tumor so that above a threshold temperature the tumor cells are destroyed. This can be accomplished by many heat supply techniques and the use of magnetic nanoparticles that generate heat when an alternating magnetic field is applied has emerged as a promise technique. In the present paper, the Pennes bioheat transfer equation is adopted to model the thermal tumor ablation in the context of magnetic nanoparticles. Numerical simulations are carried out considering different injection sites for the nanoparticles in an attempt to achieve better hyperthermia conditions. Explicit finite difference method is employed to solve the equations. However, a large amount of computation is required for this purpose. Therefore, this work also presents an initial attempt to improve performance using OpenMP, a parallel programming API. Experimental results were quite encouraging: speedups around 35 were obtained on a 64-core machine

  6. Precise determination of the heat delivery during in vivo magnetic nanoparticle hyperthermia with infrared thermography

    Science.gov (United States)

    Rodrigues, Harley F.; Capistrano, Gustavo; Mello, Francyelli M.; Zufelato, Nicholas; Silveira-Lacerda, Elisângela; Bakuzis, Andris F.

    2017-05-01

    Non-invasive and real-time monitoring of the heat delivery during magnetic nanoparticle hyperthermia (MNH) is of fundamental importance to predict clinical outcomes for cancer treatment. Infrared thermography (IRT) can determine the surface temperature due to three-dimensional heat delivery inside a subcutaneous tumor, an argument that is supported by numerical simulations. However, for precise temperature determination, it is of crucial relevance to use a correct experimental configuration. This work reports an MNH study using a sarcoma 180 murine tumor containing 3.9 mg of intratumorally injected manganese-ferrite nanoparticles. MNH was performed at low field amplitude and non-uniform field configuration. Five 30 min in vivo magnetic hyperthermia experiments were performed, monitoring the surface temperature with a fiber optical sensor and thermal camera at distinct angles with respect to the animal’s surface. The results indicate that temperature errors as large as 7~\\circ C can occur if the experiment is not properly designed. A new IRT error model is found to explain the data. More importantly, we show how to precisely monitor temperature with IRT during hyperthermia, which could positively impact heat dosimetry and clinical planning.

  7. Hyperthermia - its actual role in radiation oncology. Pt. 2

    International Nuclear Information System (INIS)

    Seegenschmiedt, M.H.; Molls, M.

    1993-01-01

    This overview summarizes the most important clinical fundamentals to implement combined hyperthermia (HT) and radiotherapy (RT) in clinical trials and reviews clinical HT-RT data obtained in superficial and medium depth tumors treated with external heating devices. In the first part we discuss the following clinical fundamentals: selection of appropriate clinical sites for HT-RT studies, selection of suitable HT-devices, principle design of clinical HT-RT studies, requirements for treatment prescription, relevant treatment endpoints, definition and assessment of a thermal enhancement ratio (TER) and therapeutic gain factor (TGF), impact of prognostic parameters on treatment stratification and statistical evaluation. In the second part we review and discuss clinical results of thermoradiotherapy (HT-RT) for advanced breast carcinoma, recurrent breast cancer, advanced head and neck tumors, cervical neck node metastases, malignant melanomas and residual microscopic disease. In addition, clinical results of pilot studies are reviewed, which have applied a triple modality approach of thermo-radiochemotherapy (HRC) for various tumors. Finally, possible future perspectives of clinical HT-RT research are outlined. (orig.) [de

  8. ‘Smart’ gold nanoshells for combined cancer chemotherapy and hyperthermia

    International Nuclear Information System (INIS)

    Liang, Zhongshi; Xie, Yegui; Liu, Shunying; Li, Xingui

    2014-01-01

    Nanomaterials that circulate in the body have great potential in the diagnosis and treatment of diseases. Here we report that ‘smart’ gold nanoshells can carry a drug payload, and that their intrinsic near-infrared (NIR) plasmon resonance enables the combination of chemotherapeutic and hyperthermia therapies. The ‘smart’ gold nanoshells (named DOX/A54@GNs) consist of (a) gold nanoshells (GNs) with NIR plasmon resonance, which not only act as nanoblocks but also produce local heat to allow hyperthermia; (b) an anticancer drug, doxorubicin (DOX), which was conjugated onto the nanoblocks by pH-dependent biodegradable copolymer thiol poly(ethylene glycol) derivatives via carbamate linkage; and (c) the targeting peptide A54 (AGKGTPSLETTP) to facilitate its orientation to liver cancer cells and enhance cellular uptake. The conjugated DOX was released from the DOX/A54@GNs much more rapidly in an acidic environment (pH 5.3) than in a neutral environment (pH 7.4), which is a desirable characteristic for intracellular tumor drug release. DOX-modified GNs showed pH-dependent release behavior, and the in vitro cell uptake experiment using ICP-AES and microscopy showed greater internalization of A54-modified GNs in the human liver cancer cell line BEL-7402 than of those without A54. Flow cytometry and fluoroscopy analysis were conducted to reveal the enhanced cell apoptosis caused by the A54-modified GNs under combined chemotherapeutic and hyperthermia therapies. These results imply that DOX/A54@GNs could be used as a multifunctional nanomaterial system with pH-triggered drug-releasing properties for tumor-targeted chemotherapy and hyperthermia. (paper)

  9. In-Bore Prostate Transperineal Interventions with an MRI-guided Parallel Manipulator: System Development and Preliminary Evaluation

    Science.gov (United States)

    Eslami, Sohrab; Shang, Weijian; Li, Gang; Patel, Nirav; Fischer, Gregory S.; Tokuda, Junichi; Hata, Nobuhiko; Tempany, Clare M.; Iordachita, Iulian

    2015-01-01

    Background The robot-assisted minimally-invasive surgery is well recognized as a feasible solution for diagnosis and treatment of the prostate cancer in human. Methods In this paper the kinematics of a parallel 4 Degrees-of-Freedom (DOF) surgical manipulator designed for minimally invasive in-bore prostate percutaneous interventions through the patient's perineum. The proposed manipulator takes advantage of 4 sliders actuated by MRI-compatible piezoelectric motors and incremental rotary encoders. Errors, mostly originating from the design and manufacturing process, need to be identified and reduced before the robot is deployed in the clinical trials. Results The manipulator has undergone several experiments to evaluate the repeatability and accuracy of the needle placement which is an essential concern in percutaneous prostate interventions. Conclusion The acquired results endorse the sustainability, precision (about 1 mm in air (in x or y direction) at the needle's reference point) and reliability of the manipulator. PMID:26111458

  10. MO-E-BRC-02: MRI-Guided Online Adaptive Radiotherapy: The UCLA Approach to Quality Management

    Energy Technology Data Exchange (ETDEWEB)

    Lamb, J. [University of California, Los Angeles (United States)

    2016-06-15

    Online adaptive radiation therapy has the potential to ensure delivery of optimal treatment to the patient by accounting for anatomical and potentially functional changes that occur from one fraction to the next and over the course of treatment. While on-line adaptive RT (ART) has been a topic of many publications, discussions, and research, it has until very recently remained largely a concept and not a practical implementation. However, recent advances in on-table imaging, use of deformable image registration for contour generation and dose tracking, faster and more efficient plan optimization, as well as fast quality assurance method has enabled the implementation of ART in the clinic in the past couple of years. The introduction of these tools into routine clinical use requires many considerations and progressive knowledge to understand how processes that have historically taken hours/days to complete can now be done in less than 30 minutes. This session will discuss considerations to perform real time contouring, planning and patient specific QA, as well as a practical workflow and the required resources. Learning Objectives: To understand the difficulties, challenges and available technologies for online adaptive RT. To understand how to implement online adaptive therapy in a clinical environment and to understand the workflow and resources required. To understand the limitations and sources of uncertainty in the online adaptive process I have research funding from ViewRay Inc. and Philips Medical Systems.; R. Kashani, I have research funding from ViewRay Inc. and Philips Medical Systems.; X. Li, Research supported by Elekta Inc.

  11. A study of MRI-guided diffuse fluorescence molecular tomography for monitoring PDT effects in pancreas cancer

    Science.gov (United States)

    Samkoe, Kimberley S.; Davis, Scott C.; Srinivasan, Subhadra; O'Hara, Julia A.; Hasan, Tayyaba; Pogue, Brian W.

    2009-06-01

    Over the last several decades little progress has been made in the therapy and treatment monitoring of pancreas adenocarcinoma, a devastating and aggressive form of cancer that has a 5-year patient survival rate of 3%. Currently, investigations for the use of interstitial Verteporfin photodynamic therapy (PDT) are being undertaken in both orthotopic xenograft mouse models and in human clinical trials. In the mouse models, magnetic resonance (MR) imaging has been used as a measure of surrogate response to Verteporfin PDT; however, MR imaging alone lacks the molecular information required to assess the metabolic function and growth rates of the tumor immediately after treatment. We propose the implementation of MR-guided fluorescence tomography in conjunction with a fluorescently labeled (IR-Dye 800 CW, LI-COR) epidermal growth factor (EGF) as a molecular measure of surrogate response. To demonstrate the effectiveness of MR-guided diffuse fluorescence tomography for molecular imaging, we have used the AsPC-1 (+EGFR) human pancreatic adenocarcinoma in an orthotopic mouse model. EGF IRDye 800CW was injected 48 hours prior to imaging. MR image sequences were collected simultaneously with the fluorescence data using a MR-coupled diffuse optical tomography system. Image reconstruction was performed multiple times with varying abdominal organ segmentation in order to obtain a optimal tomographic image. It is shown that diffuse fluorescence tomography of the orthotopic pancreas model is feasible, with consideration of confounding fluorescence signals from the multiple organs and tissues surrounding the pancreas. MR-guided diffuse fluorescence tomography will be used to monitor EGF response after photodynamic therapy. Additionally, it provide the opportunity to individualize subsequent therapies based on response to PDT as well as to evaluate the success of combination therapies, such as PDT with chemotherapy, antibody therapy or even radiation.

  12. MO-E-BRC-02: MRI-Guided Online Adaptive Radiotherapy: The UCLA Approach to Quality Management

    International Nuclear Information System (INIS)

    Lamb, J.

    2016-01-01

    Online adaptive radiation therapy has the potential to ensure delivery of optimal treatment to the patient by accounting for anatomical and potentially functional changes that occur from one fraction to the next and over the course of treatment. While on-line adaptive RT (ART) has been a topic of many publications, discussions, and research, it has until very recently remained largely a concept and not a practical implementation. However, recent advances in on-table imaging, use of deformable image registration for contour generation and dose tracking, faster and more efficient plan optimization, as well as fast quality assurance method has enabled the implementation of ART in the clinic in the past couple of years. The introduction of these tools into routine clinical use requires many considerations and progressive knowledge to understand how processes that have historically taken hours/days to complete can now be done in less than 30 minutes. This session will discuss considerations to perform real time contouring, planning and patient specific QA, as well as a practical workflow and the required resources. Learning Objectives: To understand the difficulties, challenges and available technologies for online adaptive RT. To understand how to implement online adaptive therapy in a clinical environment and to understand the workflow and resources required. To understand the limitations and sources of uncertainty in the online adaptive process I have research funding from ViewRay Inc. and Philips Medical Systems.; R. Kashani, I have research funding from ViewRay Inc. and Philips Medical Systems.; X. Li, Research supported by Elekta Inc.

  13. Motion compensation for MRI-compatible patient-mounted needle guide device: estimation of targeting accuracy in MRI-guided kidney cryoablations

    Science.gov (United States)

    Tokuda, Junichi; Chauvin, Laurent; Ninni, Brian; Kato, Takahisa; King, Franklin; Tuncali, Kemal; Hata, Nobuhiko

    2018-04-01

    Patient-mounted needle guide devices for percutaneous ablation are vulnerable to patient motion. The objective of this study is to develop and evaluate a software system for an MRI-compatible patient-mounted needle guide device that can adaptively compensate for displacement of the device due to patient motion using a novel image-based automatic device-to-image registration technique. We have developed a software system for an MRI-compatible patient-mounted needle guide device for percutaneous ablation. It features fully-automated image-based device-to-image registration to track the device position, and a device controller to adjust the needle trajectory to compensate for the displacement of the device. We performed: (a) a phantom study using a clinical MR scanner to evaluate registration performance; (b) simulations using intraoperative time-series MR data acquired in 20 clinical cases of MRI-guided renal cryoablations to assess its impact on motion compensation; and (c) a pilot clinical study in three patients to test its feasibility during the clinical procedure. FRE, TRE, and success rate of device-to-image registration were mm, mm, and 98.3% for the phantom images. The simulation study showed that the motion compensation reduced the targeting error for needle placement from 8.2 mm to 5.4 mm (p  <  0.0005) in patients under general anesthesia (GA), and from 14.4 mm to 10.0 mm () in patients under monitored anesthesia care (MAC). The pilot study showed that the software registered the device successfully in a clinical setting. Our simulation study demonstrated that the software system could significantly improve targeting accuracy in patients treated under both MAC and GA. Intraprocedural image-based device-to-image registration was feasible.

  14. Investigating the Causal Role of rOFA in Holistic Detection of Mooney Faces and Objects: An fMRI-guided TMS Study.

    Science.gov (United States)

    Bona, Silvia; Cattaneo, Zaira; Silvanto, Juha

    2016-01-01

    The right occipital face area (rOFA) is known to be involved in face discrimination based on local featural information. Whether this region is also involved in global, holistic stimulus processing is not known. We used fMRI-guided transcranial magnetic stimulation (TMS) to investigate whether rOFA is causally implicated in stimulus detection based on holistic processing, by the use of Mooney stimuli. Two studies were carried out: In Experiment 1, participants performed a detection task involving Mooney faces and Mooney objects; Mooney stimuli lack distinguishable local features and can be detected solely via holistic processing (i.e. at a global level) with top-down guidance from previously stored representations. Experiment 2 required participants to detect shapes which are recognized via bottom-up integration of local (collinear) Gabor elements and was performed to control for specificity of rOFA's implication in holistic detection. In Experiment 1, TMS over rOFA and rLO impaired detection of all stimulus categories, with no category-specific effect. In Experiment 2, shape detection was impaired when TMS was applied over rLO but not over rOFA. Our results demonstrate that rOFA is causally implicated in the type of top-down holistic detection required by Mooney stimuli and that such role is not face-selective. In contrast, rOFA does not appear to play a causal role in detection of shapes based on bottom-up integration of local components, demonstrating that its involvement in processing non-face stimuli is specific for holistic processing. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Perfusion imaging of brain gliomas using arterial spin labeling: correlation with histopathological vascular density in MRI-guided biopsies

    Energy Technology Data Exchange (ETDEWEB)

    Di, Ningning; Pang, Haopeng; Ren, Yan; Yao, Zhenwei; Feng, Xiaoyuan [Huashan Hospital Fudan University, Department of Radiology, Shanghai (China); Dang, Xuefei [Shang Hai Gamma Knife Hospital, Shanghai (China); Cheng, Wenna [Binzhou Medical University Affiliated Hospital, Department of Pharmacy, Binzhou (China); Wu, Jingsong; Yao, Chengjun [Huashan Hospital Fudan University, Department of Neurosurgery, Shanghai (China)

    2017-01-15

    This study was designed to determine if cerebral blood flow (CBF) derived from arterial spin labeling (ASL) perfusion imaging could be used to quantitatively evaluate the microvascular density (MVD) of brain gliomas on a ''point-to-point'' basis by matching CBF areas and surgical biopsy sites as accurate as possible. The study enrolled 47 patients with treatment-naive brain gliomas who underwent preoperative ASL, 3D T1-weighted imaging with gadolinium contrast enhancement (3D T1C+), and T2 fluid acquisition of inversion recovery (T2FLAIR) sequences before stereotactic surgery. We histologi