Most patients lack basic knowledge about the risks of radiation exposure from X-rays and other diagnostic imaging tests used to detect cancer, according to a survey published in the Journal of the American College of Radiology. Researchers contacted 5,462 oncology patients who had undergone diagnostic imaging at a comprehensive cancer center to determine their knowledge regarding the use and potential risks of ionizing radiation in diagnostic imaging.
The findings were summarized in a news report from Reuters.
“Our concern is that the term ‘radiation’ may have a negative bias,” lead author Dr. Joseph Steele of the University of Texas MD Anderson Cancer Center in Houston told Reuters in an email. “Essentially, that irrational fear may result in patients not agreeing to something that is in their best interest.”
The survey found that only about 22% of the respondents could correctly define ionizing radiation as a type of energy. Moreover, only about 35% of them correctly said computerized tomography (CT) scans used ionizing radiation, whereas about 29% incorrectly stated that magnetic resonance imaging (MRI) tests used ionizing radiation.
Many respondents did not understand the risks from exposure to diagnostic doses of ionizing radiation. Of 3,139 respondents who believed that an abdominopelvic CT scan carried risks, 1,283 (41%) believed sterility was a risk; 669 (21%) believed heritable mutations were a risk; 657 (21%) believed acute radiation sickness was a risk; and 135 (4%) believed cataracts were a risk. In reality, CT scans of the abdomen and pelvis don’t carry any of these risks, the authors write.
Dr. Leonard Berlin, a radiology researcher at Rush University and the University of Illinois in Chicago, suggests it’s possible that at least some of the patients’ lack of knowledge in the survey may have been due to people simply relying on their doctors to recommend needed tests and failing to ask about potential risks.
“It’s extremely rare to encounter a patient who asks, ‘Doctor, can the exam harm me in any way?’” Berlin, who wasn’t involved in the study, told Reuters by email. “Indeed, it’s rare for them to even ask how much the exam will cost.”
Repeated exposure to ionizing radiation should prompt patients to ask questions about the risks, said Dr. Hans-David Hartwig, a researcher at Wolfson Children’s Hospital in Jacksonville, Florida, who wasn’t involved in the study.
“Excessive exposure can cause damage to our body’s cells and DNA,” Hartwig said by email. “We use it for certain diagnostic imaging as it gives clear pictures of problems, aids in correct diagnosis, and is time efficient––i.e., if you have a bleed on your brain you do not want to be in an MRI scanner for 30 minutes.”
In their article, the authors conclude that most patients and caregivers do not possess basic knowledge regarding the use of ionizing radiation in oncologic diagnostic imaging.
“To ensure health literacy and high-quality patient decision-making, efforts to educate patients and caregivers should be increased,” they write. “Such education might begin with information about effects that are not risks of diagnostic imaging.”