It is described in the literature that an independent calculation of Monitor Units can detect most of the potential failures in treatment administration. Due to the laborious procedure of radiosurgery, often this check can be time consuming if you do not have the appropriate verification systems. For these reasons, it requires a user friendly tool that allows for an expeditious and independent check to ensure the proper correspondence between the prescribed and calculated dose.
With that in mind, We develop the mobile application MU QC SRS under Android environment to do an independent monitor units verification for the treatment of intracranial radiosurgery by linac and cones.
Because of the App can generate a report with the dosimetric parameters used and the deviations found between the TPS's MUs and the MU from the App, MU QC SRS can be easily integrated to a Quality Assurance program of any institution.
CALCULATION FORMALISM AND DOSIMETRIC DATA
The Calculation Formalism comes from the Eclipse Cone Planning Training Manual. You can download from myvarian.com (https://myvarian.com/) if you have access.
The dosimetric data comes from a Trilogy CLINAC, installed in The Hospital de Clinicas Caracas in Venezuela. This data were measured with stereotactic diode PTW ® TN60017, and were compared against the Golden Beam Data from Varian Medical Systems ®, finding for depths greater than dmax, differences smaller than 1.10% with σ = 0.60% for TPR for all cones, and 0.10% with σ = 0.25% for output factors (OF) of cones from 10 mm to 30 mm. For the 5 mm cone we found a difference of 2.15%. This data was introduced into the Cone Dose Calculation Algorithm from Varian Medical Systems ®.
The Tolerances uses in MU QC SRS comes from 114 AAPM report published in 2011:
Verification of monitor unit calculations for non-IMRT clinical radiotherapy: Report of AAPM Task Group 114 Medical Physics, Vol 38, Issue 1. https://www.aapm.org/pubs/reports/RPT_114.pdf
MY OWN DATA
Do you want to use your own SRS dosimetric data with MU QC SRS?
Please contact us.
MSc. Franklyn Reggio
MSc. Jugleys Seijas
This development has been introduced in September 2016, at the 7th Latin American Congress of Medical Physics (ALFIM) in Argentina. http://www.alfim2016.com/es/