Purpose: The patient dose-tracking system (DTS), which we developed, generates real-time skin-dose mapping during fluoroscopically-guided-interventional procedures by interfacing to the imaging system through a vendor-specific controller-area-network (CAN) bus. In this work we investigate modification of the DTS to incorporate the information in DICOM-standard radiation-dose structured reports (RDSR) for post-procedure skin-dose mapping with any fluoroscopic system.
Methods: During a procedure, the DTS stores in a log file the values of 30 (60) technique and geometric parameters for every exposure pulse for a single (bi-) plane imaging system; the RDSR contains 18 (36) such parameters for exposure events. The corresponding parameters were identified in the RDSR file for input into the DTS to obtain the procedure dose mapping. In the data conversion, a number of approximations had to be made. For example, the RDSR file provides only beam area and so the beam is assumed to be square. Also, whereas the DTS log file leads to dose computation for every exposure pulse, only single parameter values are available for each x-ray activation in the RDSR. A MATLAB script was developed for automatically converting the RDSR to a DTS-compatible log file for playback. To compare the two approaches, time sequences of the parameter values from clinical procedures were generated.
Results: Corresponding data was identified, so that the information provided in an RDSR file can be used in the DTS. Our analysis indicates that the CAN log files provide more detailed parameter data compared to the radiation-event data in RDSR files.
Conclusion: Although the data provided by the RDSR is not as detailed as that provided by the CAN-bus log files, its incorporation into the DTS can provide automatic generation of a final dose map and estimate of the peak skin dose for post-procedure patient dose management for any fluoroscopic imaging system.
Funding Support, Disclosures, and Conflict of Interest: This work was supported in part by Canon Medical Systems Inc.