Taking Steps to Improve Radiation Safety

March 14, 2011

Throughout the industry, radiologists and referring physicians are using a number of strategies to limit patient exposure to unneeded radiation. New programs, equipment, and contrast agents are being used together to drastically reduce the amount of radiation patients receive.

Radiology currently has two buzzwords: safety and low dose. And, it’s a trend that’s been growing for the past five years.

Throughout the industry, radiologists and referring physicians are using a number of strategies to limit patient exposure to unneeded radiation. New programs, equipment, and contrast agents are being used together to drastically reduce the amount of radiation patients receive.

Safety and low-dose vigilance really kicked into high gear when the Biological Effects of Ionizing Radiation VII report came out in 2005. Media reports over the perceived dangers of radiation exposure prompted calls for measures that would protect patients, with the two main worries being accidental over-irradiation due to CT scan protocol errors and potential cancer risks associated with radiation.

The pendulum is now swinging toward limiting doses whenever possible. Through its Image Wisely and Image Gently campaigns, the American College of Radiology (ACR) and its partners have provided guidance and encouragement for reducing the amount of radiation used with both adults and children, respectively.

“The specialty is taking steps to improve safety. When it comes to doses, it’s all about ALARA - as low as reasonably achievable,” said James Thrall, MD, ACR President and Massachusetts General Hospital radiologist-in-chief. “The good news is that there are a tremendous number of technical innovations and clinical practices that are rapidly reducing exposure from CT scanning.”

One such tactic is clinical decision support systems (CDSS) that focus specifically on radiology. They are among the most wide-spread and rapidly growing methods for improving radiation safety by preventing unnecessary tests. According to Scott Cowsill, chair of the Imaging e-Ordering Coalition and senior product manager of Diagnostic Solutions at Nuance, a CDSS can help referring physicians determine whether patients need a diagnostic test in real time at the point-of-care.

Not only does this limit the patient’s amount of radiation exposure, but also saves them the time and money wasted on unnecessary radiologic tests.

“We don’t often talk about it, but there are two impacts on the patient when it comes to diagnostic testing,” Cowsill said. “No one wants to leave the doctor’s office either not knowing whether they can have a needed test or having had the wrong one conducted. And there are many costs - time off work, babysitters, travel expenses - that all go into patients taking the time for return appointments.”

Manufacturers have also built safety features into CT scanners that can prevent over-irradiation accidents even when physician orders are incorrect. Similar to alerts that appear warning pharmacists of dangerous prescriptions, new CT scanners will shut down automatically rather than conduct an unsafe test, said James Brink, MD, chair of radiology department at Yale School of Medicine and a practicing radiologist at Yale Diagnostic Radiology.

In addition, Brink said, limiting the number of people who can enter your protocols is paramount to making sure tests are safe for all patients.

“It’s important that you have one or maybe two people who input protocols,” he said. “Not everyone should be able to change them. Lock the machines down once you’ve confirmed the protocols so that only those with special permission can alter anything. It’s just an added layer of applied vigilance.”

Brink also recommended raising the issue of radiation safety throughout your entire practice, as well as with your referring physicians.

Safer machines and extra clinical information are only part of the push toward reduced radiation exposure, however. Low-dose contrasting agents also play a big role in meeting the ALARA principle, and they are increasing in popularity, said Mark Hibberd, MD, PhD, senior medical director of global medical affairs at Lantheus Medical Imaging. The smaller doses lower the risk of accidental overdoses without sacrificing the image clarity needed to make a proper diagnosis.
“The general trend is to reduce doses and radiation to benefit the patient,” Hibberd said. “Many physicians are keen on the idea of lower doses. They are now understanding that, in radiology, lower doses are a good way to go and that they really work.”

Hibberd acknowledged, however, that physician opinion is a slow ship to turn, and many other practicing radiologists are holding out for more evidence-based data that low-dose techniques are effective.

Despite misconceptions, though, low-dose agents don’t require more scans - and the same amount or more exposure - to produce a usable image, Thrall said. While initial scans will be at a higher dose to provide a proper diagnosis, subsequent scans can be effective at lower doses. As a result, exposure is reduced between 80 to 90 percent, he said.
But the United States does have a unique problem - a higher population of overweight patients.
“We have an extra challenge here because 34 percent of Americans are obese,” Thrall said. “That has a direct impact on the amount of radiation we must use to make a proper diagnosis in both adult and child patients.”

You can’t get an accurate diagnostic scan using low-dose techniques when there is too much tissue to scan through. In those cases, he said, the need for the right diagnosis trumps the desire to limit the amount of radiation exposure.

Radiology also faces another challenge to full adoption of safety and low-dose strategies, Thrall said. Hospitals and radiology practices often keep CT scanners for more than a decade, and the rapidly changing technology could easily outpace an office’s current equipment, requiring upgrades when offices can afford them.

But, he said, the fact that advancements have occurred quickly is a positive step.

“This is the most important question radiology has faced in my 42 years of practice,” Thrall said. “We are working to prove to ourselves, our patients, and the public that we are using radiation responsibly and that, as we move forward, whatever previous risks have been associated with therapies have been eliminated by up to 90 percent.”