Validation of a radiotherapy treatment planning system using an anthropomorphic phantom and MTS-N thermoluminescent detectors.
A treatment planning system (TPS) was validated in conditions of simulated radiotherapy (RT) of an anthropomorphic tissue-equivalent phantom. Individually calibrated solid MTS-N (LiF:Mg,Ti) detectors were placed within the treatment volume in this phantom which was then repeatedly irradiated by external 60Co or 6 MV X ray beams. On the basis of TLD-measured depth-dose curves for the two beams, the relative accuracy of determining dose (of the order of 1 Gy) at live depths in a water phantom is about 0.4-0.6%. In the volume of interest representing the target volume, the relative standard difference between the calculated and measured dose values ranged between 1.3% and 2.2% for the 60Co and 6 MV X ray beams, respectively. The TPS-calculated uniformity of irradiation of that volume is within 1%. While fraction-to-fraction repeatability was within 1-2%, systematic underexposure around the reference point, by 2-3%, was found in two consecutive exposures by sets of both beams.
Waligórski
M P R
MP
Centre of Oncology, Kraków, Poland. z5waligo@cyf-kr.edu.pl
Bilski
P
P
Lesiak
J
J
Byrski
E
E
Rozwadowska-Bogusz
B
B
Barańczyk
R
R
Góra
E
E
Ochab
E
E
Olko
P
P
D000042:Absorption; D006801:Humans; D019047:Phantoms, Imaging; D011868:Radioisotopes / Q000493:pharmacokinetics* / Q000627:therapeutic use; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D013819:Thermoluminescent Dosimetry / Q000295:instrumentation / Q000379:methods*
D011868:Radioisotopes