RapidPlan development of VMAT plans for cervical cancer patients in low- and middle-income countries
Cervical cancer has a high incidence and mortality rate in low- and middle-income countries (LMICs) largely due to limited resources and insufficient staffing. Knowledge-based planning (KBP) could alleviate understaffing issues by streamlining the radiotherapy treatment planning process. Varian's KBP system (RapidPlan) was used to develop a model capable of producing volumetric modulated arc therapy (VMAT) plans for cervical cancer patients. Plan data from 46 patients previously treated at MD Anderson Cancer Center (MDACC) were used to create and train the model which was then applied to 32 patients excluded from the train...
Source: Medical Dosimetry - November 14, 2019 Category: Radiology Authors: Marisol Tinoco, Erika Waga, Kevin Tran, Hieu Vo, Jamie Baker, Rachel Hunter, Christine Peterson, Nicolette Taku, Laurence Court Source Type: research
Comparison of dose distributions between transverse magnetic fields of 0.35 T and 1.5 T for radiotherapy in lung tumor using Monte Carlo calculation
We investigated the impact of the transverse magnetic fields of 0.35 T and 1.5 T on the dose distributions for a 6 MV beam, by using a thorax phantom with a lung tumor. First, the dose distributions in the magnetic flux densities of 0 T, 0.35 T, and 1.5 T were compared by increasing the number of irradiation fields. Next, the dose distributions for stereotactic body radiotherapy (SBRT) with 5-fields for an isolated lung tumor was compared in transverse magnetic fields. All dose distributions were calculated by the Monte Carlo method. (Source: Medical Dosimetry)
Source: Medical Dosimetry - November 14, 2019 Category: Radiology Authors: Takahiro Kubota, Fujio Araki, Takeshi Ohno Source Type: research
Improving TBI lung dose calculations: Can the treatment planning system help?
Lung toxicity is a serious concern during total body irradiation (TBI). Therefore, evaluation of accurate dose calculation when using lung blocks is of utmost importance. Existing clinical treatment planning systems can perform the calculation but there are large inaccuracies when calculating volumetric dose at extended distances in the presence of high atomic number materials. Percent depth dose and absolute dose measurements acquired at 400 cm SSD with a cerrobend block were compared with calculated values from the Eclipse treatment planning system using AAA and Acuros. (Source: Medical Dosimetry)
Source: Medical Dosimetry - November 11, 2019 Category: Radiology Authors: Narottam Lamichhane, Matthew T. Studenski Source Type: research
Surface dose and acute skin reactions in external beam breast radiotherapy
The biologically relevant depth for acute skin reactions in radiotherapy is 70 µm. The dose at this depth is difficult to measure or calculate and can be quite different than the dose at a depth of as little as 1 mm. For breast radiotherapy with medial and lateral tangential beams, the skin dose depends on both the contribution from the entrance beam and the exit beam. The sk in dose has been estimated in a breast model hemi-ellipse accounting for field size, beam energy, obliquity, lack of backscatter, fractionation, size and shape of the hemi-ellipse. (Source: Medical Dosimetry)
Source: Medical Dosimetry - November 8, 2019 Category: Radiology Authors: Patrick N. McDermott Source Type: research
Evaluation of the RayStation electron Monte Carlo dose calculation algorithm
The aim of this work was to evaluate the accuracy of the RayStation treatment planning system electron Monte Carlo algorithm against measured data for a range of clinically relevant scenarios. This was done by comparing measured percentage depth dose data (PDD) in water, profiles at oblique incidence and with heterogeneities in the beam path, and output factor data and that generated using the RayStation treatment planning system Monte Carlo VMC++ based calculation algorithm. While electron treatments are widely employed in the radiotherapy setting accurate modelling is challenging (TPS) in the presence of patient being bo...
Source: Medical Dosimetry - October 16, 2019 Category: Radiology Authors: Neil Richmond, Vincent Allen, Jonathan Wyatt, Richard Codling Source Type: research
