Why CT and MRI Quality Makes a Difference
One in 11 people who get care through The Alliance network has an outpatient CT or MRI each year.
The Alliance is developing QualityPath for CT and MRI scans to guide these patients to high-quality care while creating savings for self-funded employers. QualityPath for outpatient CT and MRI scans will launch in January 2017.
CT and MRI scans are so common that they might even seem like a “routine” test to many patients. So why does quality matter?
Ask Dr. Seidenwurm
We asked Dr. David Seidenwurm to explain the impact of quality measures for CT and MRI scans. Seidenwurm provided medical expertise for the development of QualityPath quality criteria for CT and MRI scans.
Seidenwurm is a graduate of the Harvard Medical School and completed a residency in diagnostic radiology at Stanford University Medical Center and a fellowship in neuroradiology at New York University Medical Center. He is based in California and works with the Sutter Medical Group, while also consulting on quality, safety and performance measurement. He has a long-term interest in whether imaging is appropriate for the patient.
Why do you say there is a “strong case” for measuring quality in CT and MRI scans?
The first reason is, why do anything that isn’t necessary? Just on the face of it, there’s never a good case for waste.
And the second reason is that there are also some specific potential harms that can occur.
For CTs, that includes radiation exposure. You can’t really measure the harm to any one individual patient, but you can measure it for the population as a whole. A CT scan delivers radiation that is the equivalent of roughly 200 chest X-rays. As your lifetime exposure to radiation increases, so does your risk of cancer. Some research has estimated that CT scans will lead to 2 percent of future cancers in the U.S., or approximately 29,000 cases of cancer leading to 15,000 deaths per year.
There’s also the danger of false positive diagnosis, which happens in many of the common imaging procedures that are included in the QualityPath CT and MRI program. A false positive diagnosis occurs when a CT or MRI scan indicates that an illness or injury is present, even when it is not. Some of these findings occur frequently in people who don’t have symptoms, as well as in people who are having symptoms. If you adhere to specific guidelines for clinical imaging, you can avoid doing scans on people without significant symptoms, which means these people don’t risk getting a “false positive” diagnosis that leads to unnecessary additional tests or even to unnecessary treatment.
It’s worth noting that a false positive finding is different than an “incidental finding,” which occurs when a scan reveals a problem in an organ system that just happens to be adjacent to the area targeted by the CT. The QualityPath quality criteria also address incidental findings.
From your perspective, what are most important features of the CT and MRI quality criteria for QualityPath?
Some criteria deal with the quality of how the procedure is performed, and I think that’s important. But what’s most important is:
- Requirements for the hospital or clinic to have accreditation by the American College of Radiology or the Intersocietal Accreditation Commission, because that ensures that minimum quality standards accepted by our profession are followed.
- Radiation exposure guidelines that are part of the Image Gently program for children and the Image Wisely program for adults. These programs were developed by medical specialty societies to provide guidelines for safe imaging and reduce unnecessary radiation exposure.
- Evidence-based guidelines for following up on incidental findings. For example, let’s say the patient had a CT of the abdomen for pain and the radiologist observed some small nodules in the lung. There are guidelines for lung lesions that deal with the appropriate duration of follow-up for the patient, and the appropriate interval for follow-up visits. In other words, how often the patient comes back to be followed, and how long that follow-up continues if nothing worrisome is found. That depends on things like individual risk factors like smoking and how often people in the local population have benign abnormalities, which are not cancer, along with abnormalities that are cancer.
- You also have to look at the characteristics of the tests you’re going to use to follow the abnormalities, like what is the minimum size change that can reliably be detected, and what is the minimum interval at the expected rate of growth that would lead to the detection of a real change that is meaningful to the patient’s care? If the follow-up interval is too long, you might have a false diagnosis based on a change in size. If the interval time is too short, you could fail to observe a real change in the size, which would result in false reassurance. Either possibility could lead to errors, which might mean missing an important diagnosis, or it might mean a false positive diagnosis that would lead to harm in the form of unnecessary follow-up procedures.
- Standards that deal with whether the CT or MRI scan is the most appropriate imaging to use for this patient at this time. There are decision support processes built in that get at issues such as whether an X-ray was used first, when appropriate.
Can you provide an example of the harm that can occur when patients are “overdiagnosed”?
There are conditions that have such a small probability of being something serious that investigating them can cause more harm than good. There’s now an epidemic of thyroid cancer, which is treated with radiation and surgery. And yet, over years and years, there has been no decrease in the death rate from thyroid cancer. These “incidental findings” are causing treatments that patients don’t need, and those treatments carry their own risk of harm. Similarly, imaging can find incidental lesions on the adrenal glands. A couple of percent of patients have adrenal lesions, but only a very small number of those patients will have adrenal cancer. So, many of these patients don’t have cancer to start with, but they could undergo invasive diagnosis or surgery due to an incidental finding.
Radiology professionals have reached an “expert consensus” on what requires follow up and what does not. This helps distinguish tumors that will become symptomatic in a patient’s lifetime as opposed to those that are so small they would never become a problem, or those that are a type of tumor that would not become symptomatic, which means they do not pose a risk to patients. QualityPath measures related to follow-up care adhere to these standards of the radiology community.
What’s the advantage to patients for using a QualityPath provider?
When you use clinics and hospitals that have QualityPath designation for CT and MRI scans you will know:
- You need to have the scan taken.
- Your scan is being done in a safe way.
- Your scan will be of sufficient quality to be used for diagnosis.
- The practical standards of diagnosis and follow-up care are being followed.
You might want to compare this experience to getting a passport picture – you just want to make sure your picture is the right size and shape and quality so you don’t have to get it taken again, you can get a passport and you don’t end up stranded in Outer Mongolia because your picture doesn’t match your reality. QualityPath gives you greater assurance that your medical imaging is going to serve its intended purpose.
Should patients be concerned about “switching health care systems” when they use a doctor from one clinic or hospital, but get their CT or MRI scan from a different clinic or hospital?
What’s most important to the patient is that the standards for care are being met. QualityPath uses the standards that reflect the consensus of what is quality care for CT and MRI scans.
Effective communication between the clinic or hospital that does the scans and the patient’s doctor who is coordinating care is also important. QualityPath includes provisions for making sure that electronic records can be effectively shared between health systems. We’ve worked very hard to make sure that reports are communicated in the ways that doctors can receive them.
Could QualityPath standards for CTs and MRIs lead to broader changes in how images and tests are used?
The hardest thing to see in radiology is what isn’t there. For example, there are medical syndromes that are diagnosed when people are missing internal structures. Sometimes, those are hard diagnoses to make.
Likewise, in our current health care system, we don’t know what we are missing. There’s sometimes not a good flow of information. Most doctors, like most people, want to see how they’re doing and they want to do a good job. QualityPath is potentially a unique source of information for doctors that can help them monitor and improve their quality. We can help give people the knowledge and information to make things better.