General information

FDA Issues Interim Recommendations to Address CT Scan Concerns
Investigation finds 256 confirmed cases of overexposure in California.

On Oct. 8, the Food and Drug Administration (FDA) issued an Initial Communication identifying 206 patients that had been exposed to excess radiation during computed tomography (CT) perfusion imaging. The recent cases triggered a nationwide FDA investigation. Current findings from the investigation show at least 256 confirmed cases of overexposure in California, as well as possible cases in multiple states. The investigation also shows that more than one CT scanner manufacturer is involved.

Overexposure to radiation can cause hair loss, skin redness, cataracts and increase the risk of some cancers. Exposure that is higher than anticipated, but not high enough to produce immediate symptoms may go undetected and unreported for years and increase the patient’s risk of long-term effects. While the FDA cautions against overexposure, patients are urged to follow their doctor’s recommendations for receiving CT scans.

To prevent further excess exposure to radiation, the FDA has issued interim recommendations for facilities, radiologists and radiologic technologists as the agency completes its investigation. The recommendations apply to all CT perfusions images, whether brain or heart scan.

The recommendations include:

  1. Assess whether patients who underwent CT perfusion scans received excess radiation 
  2. Review your radiation dosing protocols for all CT perfusion studies to ensure that the correct dosing is planned for each study
  3. Implement quality control procedures to ensure that dosing protocols are followed every time and the planned amount of radiation is administered
  4. Check the CT scanner display panel before performing a study to make sure the amount of radiation to be delivered is at the appropriate level for the individual patient
  5. If more than one study is performed on a patient during one imaging session, practitioners should adjust the dose of radiation so it is appropriate for each study

The FDA is also advising manufacturers to review training and guides for users, reassess information that is provided to health care providers and create and implement new surveillance systems designed to quickly identify malfunctions or other problems.

A CT perfusion scan is a medical imaging technique that identifies problems in blood flow in various organs, including the heart and brain. The scan produces a 3-dimensional image and aids in the treatment and diagnosis of various medical conditions, such as strokes.

The FDA requires hospitals and other imaging facilities to report any serious injury or death related to the use of such medical devices. Should an adverse event occur or a problem with the device is suspected, health care providers should follow the facility’s reporting procedure and directly contact the device manufacturer or the FDA’s MedWatch program at; send information to MedWatch at, 5600 Fishers Lane, Rockville, MD 20852-9787; or call (800) FDA-1088.

Providers should include the following information in reports:

  1. The protocol followed during the event
  2. The CT conditions of operation (technical parameters, modes etc)
  3. The dose-index values displayed