A Holistic Approach to CT Protocol and Dose Management

Challenges from administrative support, scanners' heterogeneity, patient size variation, and protocol mapping hinder CT protocol and dose management. We present a holistic approach to overcome these challenges.

A dose tracking software was selected with two key requirements: intelligent protocol mapping and customizable dose threshold settings according to the patient size. A multifaceted workflow was carefully implemented. It included patient size-dependent dose thresholds for e-mail alerts, a base protocol archive on a website with a unified format using an in-house developed reformat software upon protocol export, prompt dose alert follow-up, and well-controlled protocol changes. The thresholds were iteratively updated following protocol changes or review of dose statistics. The program outcome was evaluated using 11 protocols from January 2020 to May 2023 (N = 148,678) in comparison to ACR's achievable dose (AD) and dose reference levels (DRLs).

The 75th percentile dose data were lower than the ACR's DRL on average, ranging from -4.9% to -36%. The median doses were in a range of -23% to 19% on average in comparison with the ACR's AD. The median value from pulmonary embolism scans initially showed 36% higher than the AD but was gradually reduced to nearly 3% lower than the AD. The percentage of unjustified alerted cases decreased from 80% in first half year of 2020 to 17% in the first 5 months of 2023.

The results showed that our holistic approach to protocol and dose management has been effective. The impact to practice has been prompt and sustainable.