Purpose: Our real-time scatter display system (SDS) has been enhanced in functionality to include automatic in-room tracking of staff members for the update of on-screen position indicators.
Methods: A circular indicator displaying local dose-rate value is positioned at the location of the staff member in the SDS. The indicator is superimposed over a virtual reality (VR) depiction which includes the color-coded room scatter distribution, a graphic of the imaging system gantry, table, and patient. For staff tracking, a robot operating system (ROS) wrapper was implemented with a Microsoft Kinect V2 depth (infrared) camera using OpenNI2 and NiTE2 for body identification. Tracking of landmark body features is accomplished and torso transformation vectors are read out for each individual directly into a text file which is then imported to the SDS. Real-time performance was then evaluated using the SDS.
Results: The refresh rate of the staff member indicator position on-screen was quantified for different values of torso coordinate frame durations for the Kinect. The torso coordinate frame durations were varied from 0.06 s up to 6.3 s and the corresponding body tracking delay time (between movement of an individual and update of the staff member indicator position on the SDS) was observed. With the current software, a coordinate frame duration of 0.06 s was determined to lead to the smoothest update of the on-screen position with a corresponding tracking lag time of 1.5 s. The SDS image frame update time for scatter distribution and dose rate update was determined to increase from 0.17 s to 0.39 s when body tracking is introduced.
Conclusion: A method for incorporating real-time staff tracking in the SDS has been developed. Display of individualized scatter dose rate information can provide feedback to staff for enhanced radiation safety in a clinical setting.
Funding Support, Disclosures, and Conflict of Interest: This research was supported by Canon Medical Systems.
Not Applicable / None Entered.