March 27, 2015
Add to Google
FDA Verdict on Patient Radiation Overdoses: Operator Error
email a friend print

Markers in the blood of people who are or will become depressed offer a step forward in early diagnosis and treatment. More >

Follow us on Twitter. Become a fan on Facebook. Receive updates via E-mail and SMS:

Would you like to ask our staff a question? >
Join the discussion and leave a comment on this article >

FDA Verdict on Patient Radiation Overdoses: Operator Error


A recently-issued FDA press release details a series of safeguards and changes in procedures designed to prevent the dangerous over-exposure to radiation from CT scans. The recommendations were prompted by two studies published in the journal, Archives of Internal Medicine, detailing the huge variation in how much radiation people undergoing CT (computerized tomography) scans are exposed to.

As far back as 2008, hundreds of patients received sizeable radiation overdoses from CT scans. The Food and Drug Administration (FDA) has now investigated, and the conclusions they have reached are both good news and bad news for patients.

The FDA found approximately 385 overdoses received by patients at five hospitals in California and one in Alabama. The New York Times reported more than 400 overdoses at eight hospitals.

The FDA wants scanner manufacturers, doctors and technologists all to pay more attention to the radiation dose each patient receives during every scan. These overdoses were fairly easy to prevent, and following the new recommendations should prevent most future ones from occurring.

Introduction: What the FDA Found

In its November press release, the FDA concludes that the overdoses were caused by scanner operator error.(1) The FDA found no fault with the scanners themselves. The press release suggests several improvements that could prevent a future repeat of these overdoses, including scanners designed to provide a specific, obvious on-screen notification to scanner operators of a high radiation dose.

In a letter to hospitals and medical professionals released the same day, the FDA details many further safety recommendations to hospitals and scanner operators.(2)

The FDA found approximately 385 overdoses received by patients at five hospitals in California and one in Alabama. An article in The New York Times reported more than 400 overdoses at eight hospitals.(3)

Eight Times the Normal Dose

The overdoses all occurred to patients who underwent a CT perfusion scan. This is a rapid series of X-rays usually given to patients who are suspected of having a stroke. Over 200 of the overdoses were of patients in a single California facility, Cedars-Sinai Medical Center. These patients received approximately eight times the radiation dose normally associated with the procedure.(4)

Such excessive radiation can lead to cancer. For various reasons, scientists cannot state with absolute certainty that a specific radiation dose will ultimately cause cancer. But the best estimates predict that each of the eight-fold overdoses has a 1 in 600 probability of causing a cancer.(5) This probability is higher in younger individuals, simply because they are likely to live many more years than an older patient would.

A Safety Feature Gone Awry

A potential stroke is a life or death situation. Proper treatment requires information, quickly, and the amount of radiation a potential stroke victim receives during a CT scan may not be the most important medical issue of the moment. But by all accounts, that is not the reason for the overdoses in these scans.

The overdoses all were from GE and Toshiba scanners and appear to have stemmed from the inappropriate use of a safety feature. GE scanners have a feature called automatic exposure control. It automatically adjusts the radiation dose according to a person's size and the body part being scanned, rather than using a fixed, predetermined radiation level. Its intent is to lower radiation doses. But when used in combination with certain machine settings that govern image clarity, its effect was to significantly raise the dose of radiation delivered to a patient.

GE claims that the feature was designed for procedures that scan multiple body parts of varying thickness. It's of limited usefulness for brain perfusion scans, which target only the brain. Hospital officials claim that GE trainers never properly explained the feature and that manuals do not point out that the feature is not designed for use in brain perfusion scans.(3)

To prevent similar mishaps from occurring in the future, The FDA issued several recommendations to the scanner manufacturers on how to make their manuals both clearer and more specific and also recommended more extensive training for scanner operators.

 1 2 | 3 | Next > 


Add Comment
NOTE: We regret that we cannot answer personal medical questions.



Characters remaining:

Readers Comments
(3) Comments have been made

Huntsville Hospital continued to overdose patients after the FDA recommendations and after it knew patients had been overdosed. This is criminal. How long had this been going on? COVER-UP! Why wasn't the radiation department shut down. Now, even more patients have been harmed.
Posted Fri, Jan. 21, 2011 at 5:27 pm EST
Neil Wagner
Hi Robert, What happened to you sounds awful. Couldn't believe some of the things I was reading while researching this piece. If the hospital runs TV commercials, this is one bit they probably won't put in them. Hopefully you'll never be put through anything like this again. Once is bad enough.
Posted Wed, Dec. 15, 2010 at 12:45 pm EST
Robert Mostacci
Hi Neil, I was one of those who Cedars held the truth from. I saw the article in the paper and connected it back to my symptoms and ct scan episode. When I called Cedars they at first told me that they contacted my daughter. They were caught off guard when I told them I did not have a daughter.Then they advised that I did not get the extra radiation. After checking with Cinga who advised I was charged for the Brain Perfusion Scan I obtained my records. At that point they could not deny it any longer. For a month I was put through hell.
Posted Tue, Dec. 14, 2010 at 4:23 pm EST

This website is certified by Health On the Net Foundation. Click to verify. This site complies with the HONcode standard for trustworthy health information:
verify here.

Copyright 2015 interMDnet Corporation. All rights reserved.
About Us | Privacy Policy | Disclaimer | System Requirements