New CT Accreditation Dose Requirements Effective January 1, 2008
Effective January 1, 2008, all sites applying for computed tomography (CT) accreditation must comply with new CT dose pass/fail criteria established by the ACR Committee on CT Accreditation. The CT accreditation program will also revise its current reference levels at the same time.
Dose Pass/Fail Criteria and Reference Levels for ACR CT Accreditation
| Examination | Pass/Fail Criteria | Reference Levels | |
| New* CTDIvol (mGy) |
Old CTDIw (mGy) |
New* CTDIvol (mGy) | |
| Adult Head | 80 | 60 | 75 |
| Adult Abdomen | 30 | 35 | 25 |
| Pediatric Abdomen (5 year old) | 25 | 25 | 20 |
* Effective January 1, 2008
To be accredited with the ACR, a CT unit must pass both the clinical and phantom image-quality tests. Beginning January 1, 2008, the phantom will fail (and, the unit will fail ACR accreditation), if the dose from the CT unit exceeds the pass/fail criteria. The facility must repeat the entire phantom portion of the accreditation testing, and pass, for the unit to be granted accreditation.
Reference levels help identify situations in which doses are above expected values and should be investigated. Units exceeding these reference levels (but remaining below the pass/fail criteria) will not fail accreditation. However, even if the unit is granted accreditation, the ACR will strongly urge the facility to consult with its medical physicist to determine if it is possible to reduce the exam dose without sacrificing image quality.
These new pass/fail criteria and reference levels are based on a detailed analysis of the dose data and image quality collected during the first three years of the accreditation program. The new requirements and recommendations consider the amount of radiation necessary for adequate image quality. Because multislice CT scanners are more prevalent since the accreditation program started, the new dose criteria and levels also incorporate a more appropriate dose descriptor (CTDIvol).
We are providing this advance notice to allow facilities adequate time to review and revise their CT protocols as necessary to comply. These latest changes will help facilities reduce unnecessary radiation dose to patients undergoing CT exams while still maintaining sufficient radiation levels necessary for appropriate diagnoses.
If you have any questions about this new requirement, please call the ACR Accreditation Hotline at (800) 770-0145.