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Michał Półtorak, Edyta Fujak and Paweł Kukołowicz

Abstract

The aim of the study was to investigate the influence of thermoplastic masks material (Klarity Medical&Equipment Co., Guangzhou, China) with different diameters of holes (ϕ 0.25 cm and ϕ 0.40 cm) on the dose distribution in the build-up region for photon beams. Measurements were made for external radiation beams produced by the linear accelerator (TrueBeam, Varian Medical Systems, Inc., Palo Alto, CA, USA) using the Markus parallel plane ionization chamber and the Unidos electrometer (both from PTW, Freiburg, Germany). Measurements were made in a solid water phantom for two photon energies 6 MV and 15 MV, at 90 cm source to skin distance, for four fields of 5 cm × 5 cm, 10 cm × 10 cm, 15 cm × 15 cm and 20 cm × 20 cm. Compared to the open field, the maximum dose with mask was closer to the surface of the phantom by about 1.4 mm and 1.2 mm for 6 MV and 15 MV X-Rays, respectively. The surface dose increase from 10% to 42% for 6 MV and from 5% to 28% for 15 MV X-Rays.

Open access

Thomas Sajeev, Mohamed Mustafa and Sanjay Supe

Dosimetrical evaluation of Leksell Gamma Knife 4C radiosurgery unit

A number of experiments was performed using standard protocols, in order to evaluate the dosimetric accuracy of Leksell Gamma Knife 4C unit. Verification of the beam alignment has been performed for all collimators using solid plastic head phantom and Gafchromic™ type MD-55 films. The study showed a good agreement of Leksell Gammaplan calculated dose profiles with experimentally determined profiles in all three axes. Isocentric accuracy is verified using a specially machined cylindrical aluminium film holder tool made with very narrow geometric tolerances aligned between trunnions of 4 mm collimator. Considering all uncertainties in all three dimensions, the estimated accuracy of the unit was 0.1 mm. Dose rate at the centre point of the unit has been determined according to the IAEA, TRS-398 protocol, using Unidose-E (PTW-Freiburg, Germany) with a 0.125 cc ion chamber, over a period of 6 years. The study showed that the Leksell Gamma Knife 4C unit is excellent radiosurgical equipment with high accuracy and precision, which makes it possible to deliver larger doses of radiation, within the limits defined by national and international guidelines, applicable for stereotactic radiosurgery procedures.

Open access

Szymon Domański, Michał A. Gryziński, Maciej Maciak, Łukasz Murawski, Piotr Tulik and Katarzyna Tymińska

for Standardization; 2001. [9] Zielczyński M, Golnik N. Rekombinacyjne komory jonizacyjne. Seria monografie IEA, Otwock-Świerk. 2000. [10] Golnik N, Pliszczynski T, Wysocka A, Zielczynski M. Determination of Dose Components in Mixed Radiation Fields by means of Recombination Chambers. 5th Symp Neutr Dosim; 1985 Sep 17-21; Munich; Germany. Luxembourg: Commission of the European Communities, p. 717-725. [11] R Core Team. R: A language and environment for statistical computing. R Foundation for Statistical Computing

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Tamer Dawod, Michael Bremer, Johann Karstens and Martin Werner

therapy for lung cancer. Int J Radiat Oncol Biol Phys. 2007 Jun;68(1):416-425. de Mooy LG. The use of carbon fibers in radiotherapy. Radiother Oncol. 1991;22(2):140-142. Murray B, Forster K, Timmerman R. Frame-based immobilization and targeting for stereotacticbody radiation therapy. Med Dosim. 2007 Summer;32(2):86-91. Polednik M, Abo Madyan Y, Schneider F, Wolff D, Bannach B, Lambrecht U et al. Breast Cancer Working Group (German Cancer Association), Evaluation of Calculation Algorithms

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Piotr Wojewnik and Jakub Żmigrodzki

References [1] Achim Westermann. JChart2D, precise visualization of data [Internet]. [place unknown: publisher unknown]; [updated 2010 Jun 19; cited 2013 Jun 23]. Available from: http://jchart2d.sourceforge.net/. [2] Below K, Dietrich K.: Medizinische Gerätetechnik. 1st ed. Haan-Gruiten: Verlag Europa-Lehrmittel; 2006. p. 126. German. [3] Directive 2006/25/EC of the European Parliament and of the Council of 5 April 2006 on the minimum health and safety requirements regarding the exposure of workers to risks arising from physical agents

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Lali Kutateladze, Nino Zakariashvili, Izolda Khokhashvili, Maya Jobava, Tinatin Alexidze, Tamar Urushadze and Edisher Kvesitadze

Contaminated Soil, Leipzig, Germany, 2000;.2: 886-887. 14. Oh B, Sarath G, Shea PJ, Drijber RA, Comfort SD. Rapid spectrophotometric determination of 2,4,6-trinitrotoluene in a Pseudomonas enzyme assay. J Microbiol Methods 2000; 42(2):149-158. 15. Parrish FW. Fungal transformation of 2,4-dinitrotoluene and 2,4,6-trinitrotoluene (TNT). Appl Environ Microbiol 1977; 34:232-233.

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Elias Alibeyki, Saeid Karimkhani, Sepide Saadatmand and Parvaneh Shokrani

Involved Field Radiotherapy in the Treatment of Patients with Early Stage Hodgkin’s Lymphoma: Update Interim Analysis of the Randomised HD10 Study of the German Hodgkin Study Group (GHSG). Blood. 2005;106(11):2673. [17] Yahalom J, Mauch P. The involved field is back: issues in delineating the radiation field in Hodgkin’s disease. Ann Oncol. 2002;13(suppl 1):79-83. [18] Hoskin P, Díez P, Williams M, et al . Recommendations for the use of radiotherapy in nodal lymphoma. Clin Oncol. 2013;25(1):49-58. [19] Herst J, Crump M, Baldassarre F, et al

Open access

Samuel N. A. Tagoe, Samuel Y. Mensah and John J. Fletcher

References [1] Tagoe SNA, Mensah SY, Fletcher JJ, Sasu E. Telecobalt Machine Beam Intensity Modulation with Aluminium Compensating Filter Using Missing Tissue Approach. Iraj J Med Phys. 2018;15(1):48-61. [2] Schlegel W, Bortfeld T, Grosu A. New technologies in radiation oncology. Springer-Verlag Berlin Heidelberg, Germany. 2006. [3] Khan FM. The physics of radiation therapy. Fourth Edition. Lippincott William and Wilkins. 2010. [4] Vaarkamp J, Adams EJ, Warrington AP, Dearnaley DP. A comparison of forward and inverse planned conformal