A software tool to automatically assure and report daily treatment deliveries by a cobalt‐60 radiation therapy device

Abstract

The aims of this study were to develop a method for automatic and immediate verification of treatment delivery after each treatment fraction in order to detect and correct errors, and to develop a comprehensive daily report which includes delivery verification results, daily image‐guided radiation therapy (IGRT) review, and information for weekly physics reviews. After systematically analyzing the requirements for treatment delivery verification and understanding the available information from a commercial MRI‐guided radiotherapy treatment machine, we designed a procedure to use 1) treatment plan files, 2) delivery log files, and 3) beam output information to verify the accuracy and completeness of each daily treatment delivery. The procedure verifies the correctness of delivered treatment plan parameters including beams, beam segments and, for each segment, the beam‐on time and MLC leaf positions. For each beam, composite primary fluence maps are calculated from the MLC leaf positions and segment beam‐on time. Error statistics are calculated on the fluence difference maps between the plan and the delivery. A daily treatment delivery report is designed to include all required information for IGRT and weekly physics reviews including the plan and treatment fraction information, daily beam output information, and the treatment delivery verification results. A computer program was developed to implement the proposed procedure of the automatic delivery verification and daily report generation for an MRI guided radiation therapy system. The program was clinically commissioned. Sensitivity was measured with simulated errors. The final version has been integrated into the commercial version of the treatment delivery system. The method automatically verifies the EBRT treatment deliveries and generates the daily treatment reports. Already in clinical use for over one year, it is useful to facilitate delivery error detection, and to expedite physician daily IGRT review and physicist weekly chart review.PACS number(s): 87.55.km

Discrepancies in Dose-volume Histograms Generated from Different Treatment Planning Systems

“…The ViewRay TM system (ViewRay Inc., Cleveland, OH), provides a unique combination of a magnetic resonance imaging system and a tri-Co-60 radiation therapy system [7]. The TPS of the ViewRay system is the MRIdian TM (version 4.1.1; ViewRay Inc., Cleveland, OH, USA); its dose calculation algorithm is based on the Monte Carlo simulation [7][8][9][10]. Based on previous studies that showed differences in DVHs among commercially available TPSs, the MRIdian system should also be evaluated.…”

Technical design and concept of a 0.35 T MR-Linac

“…The software automatically generates a report comparing both original and secondary dose calculation in terms of dose-volume-histogram (DVH) parameters as well as gamma analysis. Additionally, the vendor-supplied QA tool also compares the original treatment plan to the reoptimized daily plan regarding number of segments, segment shapes and weights, and Monitor Units [6], [22], [23], [24]. After delivery, the system generates a report containing a delivery record as well as an evaluation of recorded Monitor Units and MLC leaf positions compared to the planned values.…”

First Reported Case of Pediatric Radiation Treatment With Magnetic Resonance Image Guided Radiation Therapy

“…Detailed descriptions of the initial planning process, simulation, and MRgRT treatment device, including its imaging characteristics and dedicated treatment planning system (TPS), have been previously published. 4 , 5 , 6 , 7 For this pediatric patient, simulation comprised both CT and MRI, with use of CT as the primary data set. The gross tumor volume (GTV) was defined as the preoperative visible tumor volume with modifications accounting for return of organs to their normal anatomic position after surgery.…”

“…Detailed descriptions of the initial planning process, simulation, and MRgRT treatment device, including its imaging characteristics and dedicated treatment planning system (TPS), have been previously published 4, 5, 6, 7. For this pediatric patient, simulation comprised both CT and MRI, with use of CT as the primary data set.…”