Episode 82 – Emergency Radiology Controversies

In the U.S. over the last 15 years there has been a faster increase in emergency radiology imaging utilization than any other physician service including major procedures and lab tests. In Canada, we run up an annual radiology bill of more than 2.2 billion dollars. This escalation in imaging is likely due to a variety of factors including availability of technology, inappropriate imaging referrals, increasing patient expectations, overuse of follow-up imaging, vague reports, incidental findings, increasingly busy practices and a paucity of resources and guidelines in emergency radiology.

Some of the recommendations from a recent Canadian Choosing Wisely Campaign for emergency radiology go like this: Avoid imaging for low back pain, minor head trauma or uncomplicated headache unless red flags are present. Don’t start with CT for children suspected of appendicitis. Don’t order CT head routinely in the workup of syncope with a normal neurologic clinical exam. These are all very practical reminders.

But still we can do better. In a recent Canadian study, a whopping one in seven ED patients received a CT scan, and physician knowledge about the quantitative risks associated with CT radiation dosing was limited. There is a huge variation in utilization of CT among ED physicians. In one study, 'low users' ordered an average of 78 CT scans per 1,000 patient visits, as compared to the 'high users' who ordered 135 CT scans per 1,000 patient visits. We can minimize potentially harmful imaging while at the same time improve our diagnostic accuracy by gaining more knowledge about the specific indications of various imaging modalities in common clinical scenarios, thinking carefully about how the likelihood ratios change from pre to post imaging, understanding the limitations of different imaging modalities, predicting the radiation effects, and knowing when we really need to push for advanced imaging like MRI.

So, with the help of ‘the walking encyclopedia of EM’ Dr. Walter Himmel and North York General’s Deputy Chief of Radiology Dr. Ryan Margau, we’ll discuss a few emergency radiology controversies, pearls and pitfalls: Which patients with chest pain suspected of ACS require a CXR? What CXR findings do ED docs tend to miss? How should we workup solitary pulmonary nodules found on CXR or CT? Is the abdominal x-ray dead or are there still indications for it's use? Which x-ray views are preferred for detecting pneumoperitoneum? When should we consider ultrasound as a screening test instead of, or before, CT? What are the true indications for contrast in abdominal and head CT? How should we manage the patient who has had a previous CT contrast reaction or "allergy" who really needs a CT with contrast? What is the truth about CT radiation for shared decision making? And many more emergency radiology controversies...



Podcast interview recorded October, 2015, commentary recorded June 2016

Written summary and blog post written by Anton Helman, June 2016

Cite this podcast as: Himmel, W, Margau, R, Helman, A. Emergency Radiology Controversies. Emergency Medicine Cases. June, 2016. https://emergencymedicinecases.com/emergency-radiology-controversies/. Accessed [date].

Which patients with chest pain suspected of ACS require a CXR?

Observational studies show that >70% of patients who present with chest pain who are suspected of ACS receive a CXR. Many of these CXRs may not be necessary.

The Canadian ACS Guidelines suggest that patients can forgo CXR if they have:



* No history of CHF

* No history of smoking

* No abnormalities on auscultation



However the study that this was based on could not be validated in subsequent studies.