Treatment analysis

RadCalc’s TG 218 compliant delivery QA technology reconstructs delivered doses from EPID dosimetry or treatment log file. EPID dosimetry delivers pre-treatment and in-vivo calculations as recommended in TG 307. Acquired in-vivo images are transmitted back through the patient to determine the incident fluence, differentiating it from all other available solutions.

RadCalc EPID for pre-treatment dosimetry - tackling risks of high error sensitivity

RadCalc reconstructs the dose from the delivered pre-treatment plan on the patient’s original planning CT, giving a direct comparison with both the intended dose from the TPS and RadCalc’s 3D dose second check.
After the sensitivty RadCalc's Log File analysis and dose reconstruction for Fractional Log QA (FLQA)- monitor every treatment delivery for every patient
Reconstruct the dose delivered in the first fraction in 3D automatically and evaluate 2D BEV gamma maps for every delivered eam to ensure fidelity of the delivery to the treatment intent. tests of RadCalc's EPID Dosimetry System and Features and before Benefits we need to add a new section:

Pre-treatment verification

Prior to actual patient treatment users of RadCalc can perform independent MU and dose calculation of individual points or 3D volumes. The pre-treatment verification activities can be extended with Fluence and Dose Map image analysis. RadCalc’s calculated Dose Map can be compared with a measured Dose Map. Additionally, calculated fluence can be compared with TPS fluence or the calculated fluence from the linac log files. These pre-treatment checks can be performed with data from RadCalc Dose, Pinnacle Dose, Dicom Dose, DICOM Image, Pinnacle ODM, RadCalc Fluence, imported Fluence, MapCHECK dose map or IBA MatriXX dose map.

Fractional Machine QA

Treatment delivery data acquired during the treatment can be used for machine performance analysis. The intended plan can be compared to the delivery reconstructed from Dynalog or TrajectoryLog files, as well as RadCalc LINAC Log created from iCom data transfer for Elekta LINACs. The available analysis methods allow the calculation of the percentage dose difference, distance to agreement value and the gamma values. The statistical results are shown on a histogram, and the comparison results can be visualised along any arbitrary line in a 2D plane or as a 3D dose volume analysis.

In-vivo calculation

RadCalc can perform in-vivo diode or TLD calculations for photon and electron beams by computing an expected reading or range, based on the Dmax dose. Correction factors for photon beams may include: SSD, field size, attenuation factors, wedge factors and off-axis factors. Cone correction factors may be used for electron beams. In-vivo verification results can be collected through the whole course of treatments and can be stored together with the secondary dose verification calculations. By exporting the results to the R&V System it can be part of the complete patient documentation in one system.

Potential error detection

With phantom-based measurements

Data transfer corruption
Deliverability of dose
Checks TPS dose on phantom
Spends additional time on aligning and calibrating phantoms
Costly and time consuming

With on-board imager and RadCalc software

Data transfer corruption
Deliverability of dose
Checks TPS dose on volumetric patient image
Saves up to 20% of QA time
Uses reconstructed 3D measurements

RadCalc EPID for in-vivo dosimetry - accurate QA instead of basic measurement

In-vivo deliveries allow to reconstruct the dose delivered during the treatment, giving a direct comparison on the actual delivered dose re-constructed on the patient’s original planning CT to evaluate intra-fraction changes in the patient.

Uncertainties in dose delivery?

Patient alignment checks on x-ray
Strongly increasing risks with rising complexity of treatment
Without In-Vivo uncertainty on actual dose received by the patient

Understanding the actual dose delivered

Accurate validation:
Dose checks along the treatment
- Patient setup against treatment plan
- First fraction dose delivery vs. plan
- Patient anatomy changes
3D and EPID analysis

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Sensitivity Test of RadCalc's EPID Dosimetry System

Features

Simple

RadCalc’s EPID module utilizes the collected integrated measurements for all static and dynamic beam segments to reconstruct 3D dose on the patient’s real anatomy using RadCalc's Collapsed Cone algorithm.

Supported modalities

Supporting commercially available linear accelerators with integrated EPID panels for all treatment techniques.

True composite

Actual dose delivered is compared with both the intended dose from the TPS and RadCalc’s 3D dose reconstruction for a thorough pre-treatment QA.

Inherent sensitivity

RadCalc’s implementation exploits the inherent sensitivity of the EPID to changes in the patient making it a valuable tool for analysing deviations from the intended dose.