The American College of Radiology’s (ACR) CT Dose Index Registry (DIR) program was introduced in May 2011. The DIR is a data registry that allows institutions across the United States to send their anonymized CT exam dose information to the ACR to be saved in a database at ACR. Institutions are then provided with semi-annual feedback reports comparing their results by body part and exam type to aggregate results for adult and pediatric exams. Facilities can then compare their CT dose indices to regional and national values.

At UW, we enrolled in the DIR in May 2011 and since then have been sending encrypted DICOM structured dose report files from all of our CT scanners to ACR. Doing so required collaboration between ACR, IT, PACS personnel and the on-site physicist. Implementation involved several challenges, including software installation and data transmission consistency problems. Since numerous institutions are involved, the ACR required an exam mapping process via the Radlex Playbook to unify the protocol classification. This mapping process has been the most challenging factor in the implementation process. These challenges have been overcome and data is being successfully transmitted to and analyzed by the ACR.

The first report comparing adult patient dose data (CTDI and DLP by medical examination and by scan) between our site and others around the region and country was made available in January 2012 and the second one in September 2012.  For each exam, the report includes box-plots and histogram data for a variety of standard protocols.  The second report estimated the size specific dose estimate from the scout for each patient exam.

The ACR CT Dose Index Registry program has been very successful and is a useful tool for dose data mining and will eventually establish national benchmarks for CT dose indices.

For more information on the Registry, please see this article here!