Radiation risks in procedures prompt calls for solutions

(This story has been updated with a correction.)

The growth of fluoroscopic imaging in cardiovascular and orthopedic interventional procedures is raising fears that institutional safety protocols are not adequate to protect medical staff from increased health risks resulting from radiation exposure.

Emerging technological solutions are reducing those risks, but most are in early stages of development and not yet in widespread use, at least partly because of their costs.

Fluoroscopy, which uses X-ray beams, gives cardiologists, orthopedists and interventional radiologists a less-invasive way to perform procedures such as catheter insertions through the blood vessels, angiograms, stent placements and orthopedic surgery.

But experts say the long-term effects of frequent low-dose radiation exposure on medical staff who perform such procedures has never been fully examined. “We kind of take our safety for granted when we get into this profession as interventionalists,” said Dr. Charles Chambers, a professor of medicine and radiology at Penn State Milton S. Hershey Medical Center. “We know there are radiation issues.”

In the natural environment, people are exposed to an average of 3 millisieverts, or units of radiation absorption, a year. But patients undergoing barium fluoroscopy can be exposed to the same amount of millisieverts in two minutes. Over a 20-year career, an interventional cardiologist can be exposed to up to 1,000 millisieverts to the head and 100 millisieverts to the lower body, according to estimates by the International Atomic Energy Agency.

A February report by the Organization for Occupational Radiation Safety in Interventional Fluoroscopy found evidence of a link between interventional imaging procedures and adverse health effects on medical staff. It reported heightened risk for cataracts, tumors, reduced sperm production and birth defects. A 2013 study in the American Journal of Cardiology found 22 cases of physicians who developed brain tumors on the left side of their head, which the researchers said was linked to prolonged exposure to ionizing radiation in the interventional laboratory.

Standard practices to protect staff in interventional labs include limiting their length of exposure and increasing the distance between staffers and the radiation source. Another is wearing heavy lead shields during fluoroscopy.

But some say lead protective gear does not offer staffers full-body protection, leaving the head, neck and limbs exposed. And the use of heavy lead gear has discouraged some young doctors from going into imaging-related specialties out of fear that regular use of the heavy gear over many years will cause musculoskeletal problems.

“A large number of people were dissuaded from going into the field because of the physical labors,” said Dr. Lloyd Klein, an interventional cardiologist at Rush University Medical Center in Chicago.

Klein was the lead author of a report published in the April issue of the journal Catheterization and Cardiovascular Interventions, which found that 49% of 314 surveyed interventional cardiologists reported having at least one work-related orthopedic condition. Nearly 7% of catheterization laboratory operators said they limited the number of procedures they performed because of adverse health effects from radiation exposure, and 9% of cath lab operators reported the need to take a health-related leave of absence.

“Many physicians are very patient-oriented and just don't see—or don't want to see—the long-term effects of what they're doing,” Klein said.

Dr. Anne Roberts, chief of vascular and interventional radiology at the University of California San Diego Health System, said she and her staff limit the number of personnel in the lab during fluoroscopy procedures. Doctors also are instructed to use a common feature of newer fluoroscopes called “last image hold,” in which the last image on a monitor is digitally frozen after the radiation flow has ended. That allows doctors to continue looking at the image without exposing themselves or patients to additional radiation.

“There's no reason to keep your foot on the fluoroscopy pedal when you have that image there,” Roberts said. In her view, people are “much more careful” about radiation exposure than they were 15 years ago, and the radiation exposure that interventional radiologists face now is “a lot less.”

Innovations such as robotic-assisted systems that allow a physician to perform interventions by remote control at a safe distance could help with the radiation-exposure problem. There also are mobile protective shields that can be lowered into place from the ceiling of the interventional lab, or that can be rolled up in wheeled stands.

But Klein said those types of solutions can be cost-prohibitive for many hospitals. In addition, they distance the doctor from the patient and doctors don't necessarily like that. Hospitals and surgery centers, he said, should rethink how fluoroscopy tables and labs are designed to improve staff and patient safety. “Physicians ought not to be wearing their protection,” Klein said. “Their protection should be surrounding them.”

(An earlier version of this story has been corrected. The measurement for the human radiation exposure described is millisieverts.)