Abstract
A new radiation system known as the TomoTherapy Radixact X9 was introduced at our hospital in June 2021. From August 2021 to March 2022, 6 patients underwent total body irradiation (TBI) with tomotherapy with the Radixact X9. This paper describes the sequence of events from treatment planning computed tomography to irradiation. Results are also reported for measurements made with Gafchromic EBT3 film, the Delta4 Phantom+, and an A1SL ionization chamber dosimeter, set-up error, and time required to enter and exit the room, which were measured during plan verification. The measurement results were as follows: Gafchromic EBT3 film, 91.78±0.96% ; Delta4 Phantom+ head, 100±0% ; chest, 98.93±1.17% ; foot, 98.90±2.28% ; ionization chamber dosimeter A1SL, -0.39±0.70%; Residual error: -0.01±1.91 mm for lateral, 0.29±1.60 mm for longitudinal, 0.36±2.07 mm for vertical, -0.06±0.78° for roll. In addition, the time required to enter and exit the room was 98.50±17.17 min. TBI could be performed within set-up error of 5 mm in all cases. The validation results from the initial 6 cases confirmed that TBI with tomotherapy provided good dose distribution and positional accuracy.
