Sponsored by Banner Health
By Paul Hanny, Ph.D., DABR
Performing half a million CT exams each year, Banner Health organized a team to make significant radiation dose decreases while maintaining diagnostic image quality. Radiologists, CT technologists, medical physicists, radiation safety officers and medical imaging directors meet monthly to review the mountain of CT data. Using Bayer’s Radimetrics, CT scan parameters are organized and displayed into dashboards that compare every aspect of the CT scans. To identify steps to take to optimize the dose, Banner Health exports the CT data from Radimetrics and creates monthly reports that focus on scan parameters that offer the greatest opportunity to keep the image quality and reduce the dose.
In Banner Health, the desire for CT dose reduction grew from medical imaging department staff, radiologists and managers from 48 medical centers and imaging centers. They viewed the importance of keeping the doses low while maintaining diagnostic quality, tracking CT doses, comparing them to benchmarks and automatically entering the doses in the patients’ medical records. A systemwide approach is key to leveraging support between facilities.
Banner Technology Management/ENTECH and the Banner Medical Imaging Clinical Consensus Group (CCG) organized the systemwide approach. Bayer Radimetrics was the platform chosen to gather the data, organized it into dashboards, create alerts and enter dose into electronic records. Radimetrics could handle the mountain of CT data collected daily, and Bayer’s continued support in training and troubleshooting made the process easier. Using Bayer’s recommendations, we organized our efforts and formed a system oversight group that reports to the CCG. The oversight team includes program administrators, imaging managers, radiologists, diagnostic medical physicists, CT super users, clinical data specialists and radiation safety officers. This team meets monthly to focus on developing, implementing and managing the people, processes and technology of the radiation dose reduction initiatives with the goal of sustaining an enduring, flexible program.
We formed a CT super user group of those managing the alerts and protocols daily. The super user group meets monthly to discuss issues with the database, protocols, dashboards and alerts. The super users at each site, along with the radiologists and medical physicists, make the changes to reduce the dose and review the outcomes.
Early challenges included the amount of data, making sure it was clean data that we could use to make decisions, and that it was accurately transferred. Every clinic had unique protocol naming conventions, which led to a master lexicon of protocol names. Occasionally, after a CT unit’s preventive maintenance, the protocol names reverted to the previous names and were rejected or unreported. The super users regularly check the protocol names and scans to make sure Radimetrics accept them.
To take the data to an even more practical level, we exported data from Radimetrics and created facility-specific reports that identified the most likely scan parameters that we could change to reduce the dose. We wanted a visible scoreboard that easily compares each facility CT with the same model to see how much the protocols varied. Additionally, the monthly reports show dose trends for head, chest, abdomen/pelvis, sinus and neck CTs. Pediatric scan data are grouped by age and weight. The reports compare CTDIvol and Dose-Length-Product to national benchmarks, plus compare Size-Specific Dose Estimates (SSDE) and patient doses using ICRP 103 tissue weighting factors.
Our reports promptly identified the CTs operating in low-dose mode and the scanner models that tended to deliver higher doses for the same protocol. The scoreboard shows the mAs, kVp, rotation time collimator, and pitch, and indicates the scan parameter that gives the best opportunity to lower the dose for each CT.
Continuing challenges include staff turnover, adding to and removing CT units from service, refining the protocols to be reviewed and ensuring the data is accurate. Banner ENTECH and Bayer training reduce the impact of these changes. We saw an increase in chest and abdomen CT doses during COVID-19 peaks due to patient population changes. Although total scan numbers were lower during this time, the protocol names ordered by attending physicians were within 1% of pre-COVID months.
Health care system-wide, effective dose optimization is realized using a multilayered approach. Success doesn’t happen without a commitment from the clinic through corporate-level, good data that is accurate enough to make decisions and gathering feedback to continually improve and refine the program.
Paul Hanny, Ph.D., DABR, is a medical physicist and corporate radiation safety officer at Banner Health.