Ontario is looking to get rid of all their computed radiography (CR) mammogram units in favor of digital radiography (DR) mammogram systems.
In January of 2012 my colleague, Shelly Middleton, addressed the question, “Is digital mammography truly superior to film?” In Shelly’s piece only two categories were under discussion. Now a new major medical study further divides the digital category into CR and DR. This study asks, “Is DR truly superior to CR?” Results indicate that up to 20% of breast cancer was undiagnosed by CR mammo. This prompted the Ontario Ministry of Health to upgrade CR-based digital mammography to DR.
So, does Ontario’s decision to switch to DR mean that CR is no longer viable? Not so fast.
In all three types of mammography machine (film, CR, DR) X-rays are fired through breast tissue in order to obtain images. The patient's testing experience will be the same. The biggest difference is the way the images are processed.
Traditional film mammography records images using film which is then processed chemically the way photography negatives used to be processed. Digital mammography stores images using electronic signals and sends them to a computer, similar to the way a digital camera works.
CR mammography uses a phosphor-based plate which is “read” by a special mammo CR and then digitized into a computer. Think of the plate as the card that comes out of your camera and has to be plugged into the computer to be shared and looked at.
DR mammography is more like a digital camera connected directly to a computer- no transferring required. DR units have a detector that directly processes the X-ray image to the computer. This is much faster and, all studies agree, provides an image quality as good, if not better than anything else.
But, is DR image quality actually better? There are now three published studies. Two indicate CR is better than film and as good as DR while the most recent one indicates DR is better than either film or CR.
While studies continue and more conclusive results are brought to light other Canadian provinces like Quebec and British Columbia have said they are staying with CR mammography for now.
The CR/DR image quality debate is likely to remain open as research and development of new breast cancer detection technologies continue. As mammography providers in Canada wait for those details to emerge fully, what we can say for the field as a whole right now are some of the pros and cons of choosing DR over CR:
Pros of switching to DR mammography:
- Higher reimbursements
- Faster patient throughput
- Lower radiation dose
- Easier to store, share, and manipulate images
Cons of switching to DR mammography:
- Higher capital costs
- Higher maintenance costs
Fortunately, costs have gone down significantly for used and refurbished digital mammography systems. If you're considering upgrading, we'd love to help you find the best CR or DR option for your facility. Use the button below to learn more.