Dosimetric evaluation of a three-dimensional treatment planning system

Autor: Appasamy Murugan, Xavier Sidonia Valas, Kuppusamy Thayalan, Velayudham Ramasubramanian
Jazyk: angličtina
Rok vydání: 2011
Předmět:
Zdroj: Journal of Medical Physics, Vol 36, Iss 1, Pp 15-21 (2011)
Druh dokumentu: article
ISSN: 0971-6203
1998-3913
DOI: 10.4103/0971-6203.75467
Popis: The computerized treatment planning system plays a major role in radiation therapy in delivering correct radiation dose to the patients within ±5% as recommended by the ICRU. To evaluate the dosimetric performance of the Treatment Planning system (TPS) with three-dimensional dose calculation algorithm using the basic beam data measured for 6 MV X-rays. Eleven numbers of test cases were created according to the Technical Report Series-430 (TRS 430) and are used to evaluate the TPS in a homogeneous water phantom. These cases involve simple field arrangements as well as the presence of a low-density material in the beam to resemble an air in-homogeneity. Absolute dose measurements were performed for the each case with the MU calculation given by the TPS, and the measured dose is compared with the corresponding TPS calculated dose values. The result yields a percentage difference maximum of 2.38% for all simple test cases. For complex test cases in the presence of in-homogeneity, beam modifiers or beam modifiers with asymmetric fields a maximum percentage difference of 5.94% was observed. This study ensures that the dosimetric calculations performed by the TPS are within the accuracy of ±5% which is very much warranted in patient dose delivery. The test procedures are simple, not only during the installation of TPS, but also repeated at periodic intervals.
Databáze: Directory of Open Access Journals