Revision History

In April 2018, the FDA approved the ACR to begin to accredit DBT systems. If your facility previously received an extension of your MQSA certificate from the FDA to include this DBT unit(s), you must now accredit your DBT unit(s) with the ACR during your renewal process, and submit your FDA Certificate Extension Approval Letter with the application.  

Because DBT is considered a separate mammographic modality under MQSA,  and the image quality, QC, and personnel requirements are different from 2D, facilities must accredit the same mammography unit as two separate units.

In order to transmit the information about these units correctly to the FDA, the FFDM unit must appear before the DBT unit. If the FFDM unit is already accredited, add the DBT unit as a new unit. If the unit is completely new to your facility, you must add them both in the same application, but the FFDM unit must be entered into the application first. If the DBT portion of your unit is not being used clinically, it does not need to be accredited. The FFDM portion of the unit must be accredited, whether used clinically or not, as it is the basis for some of the QC testing for the DBT portion.

For clinical images: for both the FFDM and DBT "units" you may submit 2D synthesized images. You may submit 2D acquired images for the FFDM unit, but not for the DBT unit unless the ability to synthesize images is not available on your system. You may not submit tomosynthesis sets for accreditation. Although not recommended, you may submit the same patient for the DBT and FFDM units, but only if both units are in the same application, submitted at the same time.

For phantom images: for the FFDM "unit," you must submit a 2D acquired image. For the DBT "unit" you must submit the best tomosynthesis slice. Best slice is defined as the slice that demonstrates all the test objects in the phantom better than any other slice in the tomosynthesis set.

Digital Breast Tomosynthesis (DBT) and MQSA (from

MQSA defines a mammographic modality as “a technology for radiography of the breast.” Under MQSA, DBT is considered a mammographic modality.

While there are technological differences between DBT systems, and differences in their FDA-approved Indications for Use, the various FDA-approved DBT systems are now treated under MQSA as a single mammographic modality. Facilities that perform mammography using any of these DBT units are subject to MQSA requirements.

Under MQSA, personnel need to receive 8 hours of initial training prior to independently using any new mammographic modality, defined as a modality in which the person has not previously been trained. While the FDA’s Division of Mammography Quality Standards (DMQS) recognizes there are some features that are unique to each specific DBT system, personnel need only obtain training on one DBT system, or general DBT training, to meet the new modality training requirement. Nevertheless, personnel are encouraged to pursue additional training on the unique features of their unit(s) and providers of DBT modality training are encouraged to discuss the similarities and differences between DBT systems.

Under MQSA, the new modality training does not need to be provided by the manufacturer. The individual providing the training must be a qualified instructor, defined as “an individual whose training and experience adequately prepare him or her to carry out specified training assignments.” Each of the currently approved manufacturers, Hologic, GE, Siemens, and Fuji, offers training on its own system; however, third-party training courses as well as certain informal training can also satisfy the requirement for new mammographic modality training under MQSA. For example, peer training by a qualified peer who has previously met the 8 hours of DBT new modality training requirement is permitted.

The new modality requirement applies to all mammography personnel types, including recently graduated radiology residents, fellows, radiologists providing locum tenens services, consulting medical physicists, and mammography technologists providing per diem services. For residents and fellows, the training can be obtained during residency or fellowship and should be documented in the residency or fellowship letter. Please see DMQS’s sample residency letter.

Eight hours of general training in DBT or 8 hours of training on a particular manufacturer’s DBT system both satisfy the new mammographic modality training requirement. Documentation may include: letters, certificates or other documents from manufacturers' or other formal training courses, confirming letter from a Continuing Education Unit granting organization, or an attestation about experience with investigational units using DMQS’s recommended form.

For additional questions regarding DBT and MQSA, contact the FDA Mammography Facility Hotline at 1-800-838-7715 or

Revision History for this Article



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Article created; FAQs incorporated; No criteria changes

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