It’s not easy to order imaging. There are a large number of imaging tests available now than before, so it becomes quite tough for a physician to decide which ones to order. 

“The panel of imaging tests that are now available has grown quite dramatically and has become very, very specialized,” Max Wintermark, MD, chief of neuroradiology at Stanford University, Stanford, CA, told MDLinx. “It’s just hard for the referring physician to know about all of them and to be able to decide which one is going to be the best test for one individual patient.”

To that end, the American College of Radiology (ACR) developed Appropriateness Criteria®. These are evidence-based guidelines to help referring physicians choose the most appropriate imaging or treatment decision for specific clinical conditions. More recently, the ACR converted its Appropriateness Criteria into a searchable electronic Clinical Decision Support tool. This allows the clinician to input a patient’s condition and the tool automatically provides a list of the most appropriate imaging tests, along with the radiation dose and cost for each one, explained Dr. Wintermark.

Physicians are certainly encouraged to use the ACR’s electronic clinical decision portal, but they’re just as welcome to connect with the radiologist by phone or through electronic communication, Dr. Wintermark reminded.

To CT or not CT

What if a physician has a patient with a possible neurological condition and orders a CT scan of the brain with contrast dye? That’s a fairly specific test, but not quite specific enough.

What will happen is that the radiologist will query the referring physician about the reason for the patient’s test. If the referring physician says it’s for a brain tumor, the radiologist will perform a CT scan post contrast 3-5 minutes after the dye is injected, Dr. Wintermark explained.

But if it’s for a suspected stroke due to a blood clot, the most appropriate test is a CT-angiogram, where the CT images are taken while the dye is traveling in the arteries. Same imaging, same body part, same dye—but a very different type of test because of the timing of the pictures compared with the injection of dye.

To help patients get the most appropriate imaging, the ACR also instituted the Radiology Support, Communication and Alignment Network (R-SCAN™), for which Dr. Wintermark is a clinical advisor. The R-SCAN website lists several recommendations for appropriate imaging that may be instructive for referring clinicians. (Bear in mind that these are general recommendations; each patient should be assessed on a case-by-case basis, Dr. Wintermark advised.)

Routine chest x-ray

Routine admission or preoperative chest x-rays aren’t needed for ambulatory patients unless they have specific findings in their history and/or physical exam. Only 2% of such images lead to a change in the patient’s management, according to the ACR.

However, a chest x-ray is OK for a patient suspected to have acute cardiopulmonary disease. It’s also appropriate for a patient older than age 70 who has a history of chronic stable cardiopulmonary disease and hasn’t had chest radiography within 6 months.

Minor head injury in children

Minor head injuries are common in children and adolescents. Consequently, approximately 50% of children who wind up in hospital emergency departments with a head injury get a CT scan, many of which may be unnecessary, according to the American Academy of Pediatrics.

Unnecessary CT scans not only add undue costs to the health-care system but also increase a child’s lifetime risk of cancer because their brain tissue is more sensitive to ionizing radiation. Clinicians should first opt for clinical observation and use the Pediatric Emergency Care Applied Research Network (PECARN) criteria to determine whether imaging is indicated.

Low back pain

Low back pain is the fifth most common reason for all physician visits, according to the American Academy of Family Physicians. Some patients may literally cry for help. Nevertheless, don’t order imaging for low back pain within 6 weeks of pain onset, unless red flags are present. Red flags include severe or progressive neurological deficits or when you suspect the patient has an underlying condition, such as osteomyelitis.

“We know that imaging findings in the first 4 to 6 weeks of back pain are not necessarily tightly correlated with patient symptoms,” Dr. Wintermark said. So, conservative measures—such as rest, physical therapy, or medication—should be implemented before any imaging is done.

“Imaging is typically reserved only for the subset of patients who do not get better after 6 weeks, which probably indicates that those patients are more likely to have findings on imagining that correlate with their pain.”

“Sometimes the best imaging to get is actually no imaging at all,” he said.

This story is contributed by John Murphy and is a part of our Global Content Initiative, where we feature selected stories from our Global network which we believe would be most useful and informative to our doctor members.