TY - JOUR
T1 - Dose verification of volumetric modulated arc therapy (VMAT) by use of in-treatment linac parameters
AU - Haga, Akihiro
AU - Sakumi, Akira
AU - Okano, Yukari
AU - Itoh, Saori
AU - Saotome, Naoya
AU - Kida, Satoshi
AU - Igaki, Hiroshi
AU - Shiraishi, Kenshiro
AU - Yamashita, Hideomi
AU - Ohtomo, Kuni
AU - Nakagawa, Keiichi
PY - 2013/7
Y1 - 2013/7
N2 - Linac parameters such as the multi-leaf collimator (MLC) position and jaw position, cumulative monitor units (MUs), and the corresponding gantry angle were recorded during the clinical delivery of volumetric modulated arc therapy for prostate, lung, and head/neck cancer patients. Then, linac parameters were converted into the beam-data format used in the treatment planning system, and the dose distribution was reconstructed. The dose-volume histogram and the dose difference (DD) were compared with the corresponding values in the treatment plan. A reproducible error of in-treatment linac parameters was observed when a sudden change of beam intensity or MLC/jaw speed occurred. The maximum cumulative MU error was more than 4 MU for lung cancer cases, and the maximum MLC position exceeded 5 mm for prostate and head/neck cancer patients. However, these errors were quickly compensated for at the next control point. All treatments analyzed in the present study were delivered within 0.4 % accuracy at the planning target volume. The cumulative dose agreed with that of the plan within 3 % of the prescribed dose. The 1 % DD was 93.9, 99.9, and 93.4 % of the prescription dose for prostate, lung, and head/neck cancer patients, respectively.
AB - Linac parameters such as the multi-leaf collimator (MLC) position and jaw position, cumulative monitor units (MUs), and the corresponding gantry angle were recorded during the clinical delivery of volumetric modulated arc therapy for prostate, lung, and head/neck cancer patients. Then, linac parameters were converted into the beam-data format used in the treatment planning system, and the dose distribution was reconstructed. The dose-volume histogram and the dose difference (DD) were compared with the corresponding values in the treatment plan. A reproducible error of in-treatment linac parameters was observed when a sudden change of beam intensity or MLC/jaw speed occurred. The maximum cumulative MU error was more than 4 MU for lung cancer cases, and the maximum MLC position exceeded 5 mm for prostate and head/neck cancer patients. However, these errors were quickly compensated for at the next control point. All treatments analyzed in the present study were delivered within 0.4 % accuracy at the planning target volume. The cumulative dose agreed with that of the plan within 3 % of the prescribed dose. The 1 % DD was 93.9, 99.9, and 93.4 % of the prescription dose for prostate, lung, and head/neck cancer patients, respectively.
KW - Dose reconstruction
KW - Linac parameter
KW - VMAT
UR - http://www.scopus.com/inward/record.url?scp=84880286583&partnerID=8YFLogxK
U2 - 10.1007/s12194-013-0205-6
DO - 10.1007/s12194-013-0205-6
M3 - 記事
C2 - 23479401
AN - SCOPUS:84880286583
SN - 1865-0333
VL - 6
SP - 335
EP - 342
JO - Radiological Physics and Technology
JF - Radiological Physics and Technology
IS - 2
ER -