Open AccessLung and liver SBRT using helical tomotherapy — a dosimetric comparison of fixed jaw and dynamic jaw delivery
Author(s) -
Rudofsky Leonie,
Aynsley Eleanor,
Beck Sebastian,
Schubert Kai,
Habl Gregor,
Krause Sonja,
Debus Jürgen,
Sterzing Florian
Publication year - 2014
Publication title -
journal of applied clinical medical physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.83
H-Index - 48
ISSN - 1526-9914
DOI - 10.1120/jacmp.v15i3.4664
Subject(s) - tomotherapy , medicine , nuclear medicine , lung , dosimetry , radiation therapy , radiology
The purpose of the study was to evaluate the time effectiveness and dose distribution details of dynamic jaw delivery compared to the regular helical tomotherapy delivery mode in stereotactic body radiation therapy (SBRT) of liver and lung tumors. Ten patients with liver and ten patients with lung tumors were chosen to analyze the dose profiles and treatment times of regular helical tomotherapy delivery (2.5 cm field width) and new helical tomotherapy mode using dynamic jaw delivery with 5 cm field width. A median dose between 24 and 30 Gy was delivered in a single fraction. Regular helical tomotherapy took an average of 31.9 ± 6.7 min (lung SBRT) and 41.7 ± 15.0 min (liver SBRT). A reduction in delivery duration of 38.8% to 19.5 ± 2.9 min could be accomplished for lung irradiation ( p < 0.05) and by 50.8% to 20.5 ± 6.0 min for liver SBRT ( p < 0.05). Target coverage, as well as conformity and uniformity indices, showed no significant differences. No significant increase in organs‐at‐risk exposure could be detected either for lung or liver tumors. Therefore, use of new delivery mode with dynamic jaws improves treatment efficiency by reducing beam‐on time, while maintaining excellent plan quality. PACS numbers: 87.55.D‐, 87.53.Ly, 87.55.N‐