Revision History


There are 2 portions to your ACR Breast MRI Accreditation Program submission:

  • ACR MRI Equipment Evaluation Summary and MR Safety Checklist: see our article on Breast MRI QC

  • Clinical Image Testing: General information is provided in this article; also see our article on clinical image review categories  

Image quality and procedure performance assessments are the cornerstones of ACR accreditation programs. The breast MRI facility’s lead interpreting physician is responsible for ensuring high image quality and implementing an effective quality assurance (QA) program. Successful facilities are often those in which the staff’s commitment to high quality reflects the interests of the lead interpreting physician; therefore, the lead interpreting physician must routinely review and critique the image quality produced at the facility. Furthermore, the lead interpreting physician must understand the requirements of accreditation and demonstrate an interest in the results.


The facility must submit 1 case with a known, enhancing, biopsy-proven carcinoma clearly visible in the breast parenchyma, with laterality and location indicated on the form. The case must be a bilateral exam of native breasts (i.e., no TRAM or autologous tissue reconstructions). The MRI must be performed prior to any surgery on the breast with cancer (e.g., excisional biopsy or lumpectomy). You may submit a case of a patient with a new cancer who has had an old lumpectomy or biopsy at a different location within the breast, as long as it has a known, enhancing, biopsy-proven carcinoma clearly visible in the breast parenchyma. Needle biopsies may have been conducted either before or after the MRI; excisional biopsies must have been conducted after the MRI. The biopsy may be performed under guidance of any imaging modality (it need not be performed under MR-guidance). The biopsy need not be performed at the applicant’s facility; however, you should have a copy of the results so that you know the case was a biopsy-proven carcinoma. Do not submit a pathology report with the cancer case.


The ACR clinical image reviewers assume that the images submitted for accreditation are representative of the facility’s best work. The ACR Committee on Breast MRI Accreditation understands that images obtained during all breast MRI examinations may not meet these criteria. Consequently, sufficient time (45 days) is allowed to select a case that is an example of “best work.” ACR reviewers will evaluate images accordingly. If you have difficulty finding examples of your best work during this time period, please contact the ACR to request an extension. ACR reviewers recognize that some cases may be of adequate quality for diagnosis even though they are less than optimal. Also, some specific features of pulse sequences that are used clinically for breast MRI examinations are variable due to the physician’s personal preferences as well as the varying capabilities of different MRI systems. Despite this variability, experienced interpreting physicians are able to agree on what constitutes “acceptable” and “unacceptable” diagnostic exams based on both objective and subjective criteria. The accreditation process also provides guidance and recommendations for achieving optimal image quality beyond that which is merely acceptable.


Please note that although we ask you to select examples of your facility’s best work to submit for accreditation, we do expect that these examples are representative of the protocols your facility routinely uses (i.e., not only used once every 3 years for accreditation). In keeping with the Practice Site Accreditation Survey Agreement signed by your site’s owner or officer, we assume that “all accreditation criteria are met and that the same standard of performance is maintained during the accreditation period for all diagnostic modalities accredited” when your facility applied for accreditation.


If your lead interpreting physician has concerns about the quality of the case(s) selected relative to ACR requirements, your facility should carefully review the details in our article on clinical image review categories. If you need additional help, you should consult with a medical physicist (or MR scientist) who has experience in MRI regarding your routine protocols before selecting and submitting cases for accreditation. This is not something that can be done over the phone or on paper. Protocols differ for each manufacturer and model of equipment. The individual will need to work with your staff at the console to determine if your system will be able to accept the parameters necessary to meet the ACR requirements while ensuring that all necessary anatomy is covered and the required times, slice thickness and in-plane spatial resolution are met. The ACR cannot provide this type of consultative service.


Cases submitted for accreditation must meet the following criteria:

  • The facility’s lead interpreting physician for breast MRI must review and approve the selected cases, clinical images and completed forms and acknowledge this by signing the Test Image Data Form. Incorrect clinical images or incorrect information listed on the form may result in accreditation failure.

  • All examinations submitted must have been performed within six 6 months of the date that the testing package link was released to the facility. No images will be accepted for review that predate this date by more than six months. 

  • The case must be from an actual patient (not a model or volunteer) and must have been formally interpreted.

  • All images of a case must be from the same patient.

  • Do not submit exams from mastectomy patients. This is important because:

    • Unilateral cases do not allow ACR reviewers to evaluate your facility’s ability to acquire bilateral exams (i.e., they aren't necessarily representative of the timing or spatial resolution of a bilateral exam).

    • The reviewers will not be able to determine if both sides of the breast coil are working properly without both breasts present.

    • It eliminates symmetry that clinical readers and reviewers depend on.

  • You may submit a case from a patient with implants, as long as the exam is bilateral and the implants are in place with the native breast tissue. Cases from patients who have implants for mastectomy reconstruction should not be submitted. Cases from patients reconstructed with TRAM, latissimus or other autologous tissue flaps (with or without implants) should not be submitted.

  • Each case must include localizer or scout sequences. You should remove the lines from the scout/localizer images before submitting them to the ACR if possible; however, you may submit them with the lines if you cannot remove them.

  • You may submit cases for accreditation review with motion correction so long as all submitted cases are examples of your “best work.”


Each case must include the 4 sequences detailed in the table below:


Sequence

Criteria

T2 Weighted/Bright Fluid Series

  • Adequate SNR/Not too grainy

  • Sufficient bright fluid contrast

Multi-Phase T1-Weighted Series


Pre-Contrast T1

  • Adequate SNR/Not too grainy

Early Phase (first) Post-Contrast T1

  • Adequate SNR/Not too grainy

  • Completed within 4 minutes of completion of injection

  • Technical factors match pre-contrast T1

Delayed Phase (last) Post-Contrast T1

  • Adequate SNR/not too grainy

  • Technical factors match pre-contrast T1

Note: Aurora systems acquire a pre-contrast T1- weighted series that is also a T2-weighted/bright fluid series. For those cases, only 3 sequences need be submitted. If the pre-contrast series is sufficiently T2-weighted, it can be evaluated as both the T2-weighted/bright fluid series and the pre-contrast T1-weighted series. In this case, enter the acquisition parameters under “Pre-Contrast T1” on the Test Image Data form; in the “Sequence name/type” space under “T2-Weighted/Bright Fluid Series,” check “see precontrast T1W.” Do not fill out the remaining parameters for the T2-weighted/bright fluid series.

 

Specifications for the T2-weighted/bright fluid series: May be run as a single series on both breasts or as 2 separate series, 1 on each breast. In the latter case, 2 separate series numbers and data should be entered in the Test Image Data form under “T2-Weighted Bright Fluid Series” so the reviewers will know that you did both breasts with a T2-weighted series. You do not need to bind them into a single series.

 

Specifications for the multi-phase T1-weighted series: The intent of early phase and delayed phase post-contrast imaging is to capture information on lesion enhancement in the early and late phases of post-contrast enhancement.

  • Must be run bilaterally, with both the left and right breasts in the same series.

  • May be in 3 separate series, in 2 series (i.e., 1 for pre-contrast, the rest for post-contrast), or in a single series (i.e., pre-contrast and post-contrast).

  • All 3 multi-phase series (with the exception of Aurora systems) should match in terms of spatial and temporal parameters. Some small deviations may exist in the parameters listed in the series DICOM header files (e.g., in TR and TE values) between the pre- and post-contrast series. As long as these differences are small and do not affect the ability to subtract pre- from post-contrast series, such small differences are acceptable. Aurora EDGE software uses a distinctly different acquisition time for the pre- contrast series compared with that of the post-contrast series. This difference is acceptable.

  • The ACR does not require subtracted images for Breast MRI Accreditation; however, if chemical-shift (i.e., frequency-selective) fat suppression is not used or is not evident in the multi-phase T1 weighted series, then subtraction of pre-contrast from post-contrast series may be used to eliminate the bright signal from fat. If this is done, then both the unsubtracted (source) series and the subtracted series (i.e., pre-contrast subtracted from post-contrast, slice by slice) must be included for both the early and delayed phases.


If possible, only submit the required sequences. If incomplete or incorrect sequences are submitted, the unit fails accreditation. We understand that some systems do not allow for the separation of sequences without conducting special reconstructions. The ACR will accept additional sequences under this circumstance, as submitting all the sequences performed is preferable to providing reconstructions that may alter the signals between the pre- and post-contrast series.


If possible, each sequence should be presented separately and not as “stacked” or “interleaved” sequences (contact your MRI manufacturer representative for assistance). If your manufacturer informs you that it is impossible for your equipment to present the sequences separately, we will accept them; however, reviews may be delayed due to the difficulty of reviewing these cases.


Facilities applying for accreditation are not required to submit phantom images for accreditation review at this time; however, the ACR may require phantom image submission as this accreditation program matures.



Revision History for this Article

Date

Section

Description of Revision(s)

12-12-19

All

Article created; FAQs incorporated; No criteria changes



Previous: Reporting: Breast MRINext: Clinical Image Review Categories: Breast MRI