Enhancing Radiographic Quality Assurance through Systematic Monitoring of Deviation Index Data – Automation to Mitigate Dose Creep
Abstract
Purpose
AAPM TG Report 232 recommends deviation index (DI) action limits of ±1 and ±2 SD based on site radiographic exam data. However, obtaining DI data can be arduous and time-consuming. We propose a solution to efficiently and continuously monitor DI data with potential applications in dose creep prevention, quality assurance (QA), and protocol optimization.
Methods
Following a radiologist’s request to investigate a saturation artifact in a portable chest x-ray exam, exposure index (EI) and (DI) data were physically collected from 12 portable X-ray units with mean and SD of DI values calculated and reported. Physical collection of this data is time consuming and often requires dedicated vendor login information. To reduce the challenges in accessing this data, a collaboration was initiated between our hospital’s RIS and medical physics teams, developing and implementing a monitoring solution based on automated DICOM routing using an intermediate DICOM node. Studies are filtered based on DICOM tag (0008,0061) – “Modalities in Study”. Studies containing “CR” or “DR” are routed to a RIS server where relevant DICOM information, including EI and DI, is extracted and stored to a structured query language (SQL) database that can be accessed through a web portal within our hospital’s intranet.
Results
DI values from 19,297 chest exams obtained from portable X-ray units had a mean DI of 0.85 (SD=2.75), with 70.16% falling within ±1SD, and 94.76% falling within ±2SD of the mean. Our automated solution demonstrated potential for saving 20 hours per data collection from extracting EI and DI dose statistics manually, allowing for continual, efficient monitoring of dose data.
Conclusion
With the creation of a website based on relevant study SQL data, this team-based approach could reduce physicist time burden and allow for automated periodic monitoring and clinical implementation of a radiographic QA program.