Setting the Record Straight on Radiology Myths
Experts discuss the importance of dispelling misunderstandings that may have a negative effect on patient care
Outdated beliefs about radiology are still shaping clinical decisions in ways that can delay diagnoses, prompt unnecessary precautions and compromise patient care.
“Many patients and non-radiologist medical professionals have misconceptions about certain aspects of radiology,” said Laszlo Szidonya, MD, PhD, an assistant professor of radiology in the molecular imaging and therapy and neuroradiology sections of the Department of Radiology at Oregon Health & Science University (OHSU) in Portland.
Dr. Szidonya is the lead author of a RadioGraphics article that explored common misconceptions related to radiology and the myths he and his coauthors encounter on a regular basis.
For example, Dr. Szidonya said a shellfish allergy does not bar a patient from receiving iodinated contrast. “The myth comes from case reports from the 1940s, when patients had severe, sometimes fatal allergic reactions to early, ionic contrast agent—for example, diodrast—and this was attributed to ‘iodine sensitivity,’” Dr. Szidonya noted. “As iodine is an essential element necessary for human health, it is not possible to have an allergy to elemental iodine.”
Still, iodinated contrast agents can cause adverse reactions, some of which are due to an allergic reaction to the non-iodine parts of the molecule. “This confusion can lead to people refusing a contrast-enhanced CT, compromising the diagnostic value of their exam, and leading to suboptimal care,” he said.
The same pattern applies to another long-standing belief in radiology: that patient shielding should be used whenever possible.
Lindsay DeWeese, PhD, a study coauthor and associate professor and section chief of imaging physics in the Department of Radiology at OHSU, said that misconception also stems from outdated research.
“The myth persists because of studies done on fruit flies before the 1950s that looked at heritable effects of radiation,” she said. “The reality is that heritable effects have never been observed in humans.”
“But because of the technology we use now, patient shielding does not provide a clear benefit,” Dr. DeWeese added. “If shielding gets into the image, it degrades the quality of the image and the diagnostic information that is being examined. It can also result in the need to repeat the image, which results in a higher overall dose.”
When Contrast Fears Outlast the Evidence
Yet another myth is that patients with renal dysfunction should avoid iodinated IV contrast agents or be given a lower dose, according to coauthor Alice Fung, MD, professor of radiology in the body imaging section of the Department of Radiology at OHSU.
“The early literature associating contrast administration with acute renal injury examined the effects of intraarterial rather than intravenous contrast administration, and did not differentiate causality from coincidence,” she said.
Studies from the last 20 years suggest that contrast-induced acute kidney injury (CI-AKI) is much less common than previously believed, she said, adding that decreased contrast dose can increase the possibility of poor imaging quality and should not be used as a method to avoid CI-AKI.
For Dr. Szidonya, the gap between lingering belief and current evidence underscores a broader responsibility for radiologists. “Radiologists should stay up to date with the latest consensus guidelines from the American College of Radiology and other professional societies so they can communicate effectively with patients and non-radiologist medical professionals to dispel these kinds of myths,” he said.
Taking an Operational View
Radiology myths persist in large part due to operational causes, according to Ritu R. Gill, MD, MPH, a professor of radiology in the Department of Radiology at the Columbia University Irving Medical Center/New York-Presbyterian Hospital in New York City.
Dr. Gill is a strong proponent of evidence-based imaging utilization research and the ways clinical decision support tools can change ordering behavior and reduce outdated imaging practices.
“The myths live inside electronic health record (EHR) allergy fields, clinical decision support rule sets, pre-procedure order panels, technologist scripts and consent forms,” Dr. Gill said. “None of these are easy to change, and none update automatically when the literature does.”
Adding to this is that the level of published literature is often not sufficiently robust to trigger a change in belief, Dr. Gill noted.
“The myths live inside electronic health record (EHR) allergy fields, clinical decision support rule sets, pre-procedure order panels, technologist scripts and consent forms. None of these are easy to change, and none update automatically when the literature does.”
— RITU GILL, MD, MPH
“Every one of these misconceptions translates into something the patient feels: a delayed diagnosis, a refused exam, an inflated dose conversation, an isolation order that separates them from their family, an allergy entry that follows them through every future hospital visit,” she said. “Operational fixes only matter if the patient ends up with a faster, safer and more honest encounter at the end.”
Taking as an example the myth related to iodine and shellfish, Dr. Gill noted that the operational damage is enormous.
“Allergy alerts in the EHR trigger automatic premedication protocols, exam delays, modality substitutions to MRI (which cost more and take longer), and sometimes outright cancellations—all for a contraindication that doesn’t exist,” she said. “The fix must be at the system level.”
“Rewrite the allergy fields such that ‘iodine’ or ‘shellfish’ redirect to a contrast-specific question, give patients a clear explanation when an entry is corrected, and use every alert as a re-education opportunity,” she said.
Radiologists have an active role to play in dispelling common myths in radiology—they won’t fade on their own, Dr. Gill noted. She also urges non-radiologists to recognize that ordering decisions made with outdated assumptions cause real harm: missed diagnoses, delayed care, unnecessary procedures and avoidable patient anxiety.
“The evidence has moved, and our shared workflow needs to move with it,” she said.
For More Information
Access the RadioGraphics article, “Radiology Myth Busters: Debunking Common Radiology Misconceptions.”
Read previous RSNA News stories on safety in radiology: