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[en] Source anisotropy is a very important factor in brachytherapy quality assurance of high dose rate HDR Ir 192 afterloading stepping sources. If anisotropy is not taken into account then doses received by a brachytherapy patient in certain directions can be in error by a clinically significant amount. Experimental measurements of anisotropy are very labour intensive. We have shown that within acceptable limits of accuracy, Monte Carlo integration (MCI) of a modified Sievert integral (3D generalisation) can provide the necessary data within a much shorter time scale than can experiments. Hence MCI can be used for routine quality assurance schedules whenever a new design of HDR or PDR Ir 192 is used for brachytherapy afterloading. Our MCI calculation results are comparable with published experimental data and Monte Carlo simulation data for microSelectron and VariSource Ir 192 sources. We have shown not only that MCI offers advantages over alternative numerical integration methods, but also that treating filtration coefficients as radial distance-dependent functions improves Sievert integral accuracy at low energies. This paper also provides anisotropy data for three new Ir 192 sources, one for microSelectron-HDR and two for the microSelectron-PDR, for which data currently is not available. The information we have obtained in this study can be incorporated into clinical practice
Source
Christofides, Stelios; Pattichis, Constantinos; Schizas, Christos; Keravnou-Papailiou, Elpida; Kaplanis, Prodromos; Spyros, Spyrou; Christodoulides, George; Theodoulou, Yiannis (eds.); Cyprus Association of Medical Physics and Biomedical Engineering (CAMPBE), Nicosia (Cyprus); The Department of Computer Science, University of Cyprus, Nicosia (Cyprus); 220 p; ISBN 9963-607-14-4; 
; 1998; p. 131; 8. Mediterranean Conference on Medical and Biological Engineering and Computing (Medicon '98); Lemesos (Cyprus); 14-17 Jun 1998
; 1998; p. 131; 8. Mediterranean Conference on Medical and Biological Engineering and Computing (Medicon '98); Lemesos (Cyprus); 14-17 Jun 1998
[en] The Synovectomy by Neutron capture has as purpose the treatment of the rheumatoid arthritis, illness which at present does not have a definitive curing. This therapy requires a neutron source for irradiating the articulation affected. The energy spectra and the intensity of these neutrons are fundamental since these neutrons induce nuclear reactions of capture with Boron-10 inside the articulation and the freely energy of these reactions is transferred at the productive tissue of synovial liquid, annihilating it. In this work it is presented the neutron spectra results obtained with moderator packings of spherical geometry which contains in its center a Pu239 Be source. The calculations were realized through Monte Carlo method. The moderators assayed were light water, heavy water base and the both combination of them. The spectra obtained, the average energy, the neutron total number by neutron emitted by source, the thermal neutron percentage and the dose equivalent allow us to suggest that the moderator packing more adequate is what has a light water thickness 0.5 cm (radius 2 cm) and 24.5 cm heavy water (radius 26.5 cm). (Author)
Source
Gaona, E. (ed.) (Universidad Autonoma Metropolitana, Mexico D.F. (Mexico)); Huitron, B.G. (ed.) (Universidad Autonoma del Estado de Mexico, Toluca (Mexico)); Asociacion Latinoamericana de Fisica Medica (ALFIM) (Mexico); Sociedad Espanola de Fisica Medica (SEFM) (Spain); Secretaria de Salud de Mexico (Mexico); Instituto Nacional de Cancerologia (Mexico); Organismo Internacional de Energia Atomica (IAEA), Vienna (Austria); Organizacion Panamericana de la Salud (Mexico); Organizacion Internacional de Fisica Medica (Mexico); Universidad Autonoma Metropolitana (Mexico); Instituto Nacional de Investigaciones Nucleares (Mexico); Universidad Autonoma del Estado de Mexico (Mexico); Universidad Nacional Autonoma de Mexico (Mexico); Direccion de Riesgos Radiologicos (Mexico); Comision Nacional de Seguridad Nuclear y Salvaguardias (Mexico); Sociedad Mexicana de Radioterapeutas, A.C. (Mexico); Centro de Investigacion y Estudios Avanzados, IPN (Mexico); Centro Universitario contra el Cancer, UANL (Mexico); Asociacion Mexicana de Fisica Medica, A.C. (Mexico); Sociedad de Fisica Medica de Nuevo Leon, A.C. (Mexico); Sociedades Nacionales de Fisica Medica de Latinoamerica y el Caribe (Mexico). Funding organisation: Med-Tec (United States); Nucletron (Mexico); Grupo Venta Internacional, S.A. de C.V. (Leibinger) (Mexico); PTW Freiburg (Germany); Scanditronix Medical AB (Mexico); Kodak (United States); Electronica y Medicina, S.A. (Mexico); Siemens (Germany); Electronica 2000, S.A. de C.V. (Mexico); 283 p; ISBN 968-835-419-8; ; 1998; p. 254-257; 1. Ibero-Latin American and Caribbean Congress on Medical Physics; 1. Congreso Iberolatinoamericano y del Caribe de Fisica Medica; Mexico, D.F. (Mexico); 22-25 Nov 1998
; 1998; p. 254-257; 1. Ibero-Latin American and Caribbean Congress on Medical Physics; 1. Congreso Iberolatinoamericano y del Caribe de Fisica Medica; Mexico, D.F. (Mexico); 22-25 Nov 1998
No abstract available
Source
Babyij, Ya.S. (ed.); Ministerstvo Zdravookhraneniya Ukrainskoj SSR, Kiev (Ukraine); Nauchno-Issledovatel'skij Rentgeno-Radiologicheskij i Onkologicheskij Inst., Kiev (Ukraine); Khar'kovskij Nauchno-Issledovatel'skij Inst. Meditsinskoj Radiologii, Kharkov (Ukraine); Asotsyiatsyiya radyiologyiv Ukrayini, Kyiv (Ukraine); Naukovo-Tekhnyichnij zbyirnik; v. 1; 140 p; ISBN 966-95116-3-1; ; 1997; p. 18-19; Meditsina Ukrayini; Kyiv (Ukraine); Republican scientific and practical conference on radiation diagnosis and radiation therapy; Respublyikans'ka naukovo-praktichna konferentsyiya: promeneva dyiagnostika, promeneva terapyiya; Kharkov (Ukraine); 17-18 Sep 1997
; 1997; p. 18-19; Meditsina Ukrayini; Kyiv (Ukraine); Republican scientific and practical conference on radiation diagnosis and radiation therapy; Respublyikans'ka naukovo-praktichna konferentsyiya: promeneva dyiagnostika, promeneva terapyiya; Kharkov (Ukraine); 17-18 Sep 1997
[en] Since 1989, an international collaboration group, with support from the European Commission and from numerous national grant agencies, has been working to establish boron neutron capture therapy (BNCT) with epithermal neutrons as an alternative therapy for high-grade glioma. A total of 15 European countries are working toward this goal
Journal
[en] Neutron capture therapy (NCT) is a binary therapeutic modality with significant potential for the treatment of localized tumors in humans. The NCT relies on selective uptake and/or retention within tumor of a nontoxic neutron capture agent (NCA) containing a neutron capture element such as 10B and irradiation of the tumor with an appropriate-energy neutron beam. The development of tumor-affinative capture agents is requisite for efficacious NCT, particularly those NCAs that specifically localize to vital organelles such as mitochondria and nuclei. Various methods have been utilized to determine tumor and normal tissue boron levels. Few, however, have successfully localized neutron capture elements, in vivo, at the ultrastructural level, which is crucial for determination of radiation microdosimetry. This paper describes experimental results of NCT on gliosarcomas in rats
Journal
[en] The paper deals with a study of methods to improve the efficiency of combined treatment of oncological patients with a not quite favourable forecast. Radiation therapy methods producing a systematic antitumor effect are proposed. The systematic radiation therapy (SRT) is aimed at producing a tumoricidal effect on multiple obvious subclinical and occult tumor centers. The perspectives of SRT development include the expansion of radiobiological investigations in the clinic, which investigations will enable a more comprehensive idea of the mechanism of SRT action
Journal
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