Application features

• Web user interface
• Matlab user interface
• Automated workflow
• vCT generation based on CBCT images
• WET computation on vCT
• Range-corrected dose distribution
• Clinical indicators calculated on WET
• Flagging per indicator

The Daily Plan Evaluation application quantitatively assesses WET and dose distributions using CBCT for proton therapy. The workflow provides clinical indicators similar to those for repeat CT on patients with considerable interfractional anatomic changes. The dose is recalculated on a virtual CT scan (vCT) computed by deforming the planning CT onto a cone beam CT acquired in the treatment room. A more accurate, offline, Monte Carlo dose recalculation can be performed as well to determine whether a rescan CT for replanning is required.

Target users:

• Researchers
• Physicists

Publications using the application

1. A comprehensive evaluation of the accuracy of CBCT and deformable registration based dose calculation in lung proton therapy.
2. First Clinical Investigation of Cone Beam Computed Tomography and Deformable Registration for Adaptive Proton Therapy for Lung Cancer.
3. Feasibility of automated proton therapy plan adaptation for head and neck tumors using cone beam CT images.

An image arriving on the Orthanc DICOM server, from an external source, automatically triggers a new evaluation. Having set the patient input parameters, clinical indicators constraints and flagging criteria using the web interface, when a daily CBCT gets pushed to Orthanc, the CAPTAIN workflow manager executes the computations in openREGGUI to update the indicators. The results are displayed in a web interface to help take a decision whether to adapt the treatment plan or not.

Orthanc

• Receives CT, CBCT, RT Ion-Plan, RTStruct DICOM files from the OIS/TPS system. Alternatively, the files can be loaded into Orthanc via a direct web interface or by a third party application.
• Stores for future use vCT files generated by the workflow in OpenREGGUI.

• Web interface: collects user defined input concerning patient, clinical indicator constraints and flagging criteria.
• Database: stores user inputs, workflow configurations and calculation outputs.
• Workflow manager: defines set of rules workflow automation. For example, the clinical indicators automatic update when a new CBCT image arrives on the Orthanc server.

• Computes the virtual CT by deforming the planning CT onto the CBCT.
• Computes the Water Equivalent Thickness (WET) along the beam path on the vCT image.
• Based on WET derives dosimetric and non-dosimentric clinical indicators.
• Sends clinical indicator results back to Captain DB and the vCT to the Orthanc DICOM server.