The phantom portion of the American College of Radiology (ACR) Computed Tomography (CT) accreditation program: Practical tips, artifact examples, and pitfalls to avoid

TLDR

The ACR CT accreditation program, initiated in 2002, requires submission of about 20 images, multiple data sheets, and three Excel worksheet printouts. This review supplements ACR instructions by providing additional phantom setup photos, ROI and image placement examples, and a discussion of CT dose measurement techniques to aid physicists. The authors demonstrate phantom setup, ROI selection, and image placement on film sheets, and discuss dose measurement methods and calculations. The review identifies common and uncommon mistakes, offering explanations and guidance to prevent errors during accreditation submissions.

Abstract

The ACR CT accreditation program, begun in 2002, requires the submission of approximately 20 images, several completed data sheets and printouts of three Excel worksheets. The procedure manual is very detailed, yet participants unfamiliar with the program or having minimal CT experience have needed to redo aspects of their submission, or in some cases do not receive accreditation, due to mistakes made by the physicist. This review of the phantom portion of the ACR CT accreditation program supplements the ACR provided instructions with additional photos of phantom setup, region-of-interest (ROI), and image placement on the film sheets, and examples of completed portions of actual (but anonymous) submissions. Common mistakes, as well as uncommon but interesting images, are shown and explanations are given as to what could have been done to avoid the problem. Additionally, a review of CT dose measurement techniques and calculations will enable the physicist to better assist sites where typical exam doses are above the ACR reference values.