The push for this regulation came about after hundreds of cases of radiation overdoses at a prominent hospital in Southern California were made public.
When President Barack Obama opted for a virtual colonoscopy during his annual physical early this year, that choice fueled a debate about the growing use of powerful CT scanners. The machines can perform a wide range of high-end imaging tests, but according to a recent study at UCSF, may also pose radiation risks.
"The doses from CT are higher than commonly known," says Rebecca Smith-Bindman, MD, from UCSF.
Smith-Bindman led the study, which followed the radiation exposure of more than 1,000 patients receiving the most common diagnostic tests involving computed tomography. It found that doses of radiation given for similar tests varied widely depending in part on hospital protocols and even which technician was operating the machine.
"They're highly variable. So if a patient goes into the hospital or a clinic, the dose they receive for the same type of study can vary up to 20 fold depending on who they happen to see," says Smith-Bindman.
She found some of the highest doses approached levels linked to radiation poisoning. The Food and Drug Administration also expressed concern last fall, after Cedars-Sinai Medical Center in Southern California admitted that it had mistakenly overdosed more than 200 patients during CT scans, giving some patients up to eight times the normal dose which is the equivalent of 50,000 chest X-rays.
Because of those concerns, California lawmakers recently passed a bill that will put new safety measures in place, to protect patients from receiving too much radiation.
The bill requires hospitals and other facilities to record the actual level of radiation delivered during CT scans and to include that information in the patient's medical file as well as the CT scan report. Any dosages 50 percent or more above normal would have to be reported to the health department.
The bill also sets up a new accreditation program for CT technicians, though it does not provide money to pay for the training.
"We may be creating a big brother bureaucracy, lots of regulation for something that may be better solved by a bottom up, rather than a top down approach," says Fergus Coakley, MD, a professor of radiology at UCSF.
Coakley helped push for a radiation safety committee. Still, he believes that improved safety technology being built into newer machines could soon solve many of the problems without excessive regulation.
"Maybe it's a little bit like the deepwater horizon, that the regulations tend to respond to the last problem and not the next problem of the next generation of technology," says Coakley.
Despite the added costs, Smith-Bindmann believes the use of computed tomography is becoming so widespread that regulations are justified.
"This is a small drop in the bucket to try to improve the safety of what we do," says Smith-Bindmann.
A report that will appear in the October issue of "Radiology" is calling on a national collaborative effort to develop evidence-based criteria for the appropriate use of imaging technology.
