There are over 70 million CT scans performed in the United States every year. The FDA is investigating problems with overexposure to radiation by CT scans. This is an ongoing problem everywhere but is complicated by significant overexposure of special types of CT scans (called perfusion CTs) at two hospitals.
First, some background: CT scans (also called CAT scans, or computerized tomography) is an x-ray that uses radiation to visualize internal structures of the body through a cross-section of images (unlike the flat images of normal x-rays). One CT scan is equivalent to about 100 chest x-rays. One perfusion CT scan (used to examine blood vessels and often used to diagnose stroke or aneurysm) is equivalent to several hundred chest x-rays.
Sample Perfusion CT
Many physicians have been concerned about the protocols for delivering x-rays and CT scans for years. A recent study by Dr. Rebecca Smith Bindman, published in the Archives of Internal Medicine, reports that there are significant variations in radiation dosage across many CT scans. Some machines provide 13 times more radiation than others doing the same job. The study reports that one in every 250 patients who have CT scans of the abdomen or pelvis will probably get cancer from the scan. Obviously, patients who receive higher doses are at a higher risk. An editorial in the same journal, by Rita Redberg, M.D., is here. Another study, by Amy Berrington de Gonzalez, et al., is here.
The National Cancer Institute estimates that 29,000 cases of cancer and 15,000 deaths can be linked to overexposure of radiation from CT scans every year.
The FDA reports that it is investigating potentially defective CT scanners in three hospitals in Los Angeles County and one hospital in Huntsville, Alabama. They have received reports of 256 people who have received overdoses of radiation. In those hospitals, perfusion CT scans have incorrectly pumped radiation equivalent to several thousand chest x-rays into individual patients. There is no word on whether this was because of human error or machine error (the machines used were manufactured by GE Healthcare and Toshiba).
Effects of radiation exposure include reddening of the skin, loss of hair, flaky skin, cataracts, fatigue, dizziness, nausea, inability to eat, and tissue destruction, besides cancer.
Some safety questions to ask your doctor and radiologist before you go in for scans include:
- Are there alternatives to this exam?
- Is this machine calibrated to my size, diagnosis, and region of the body being scanned (particularly important for children and infants)
If you believe that you or a loved one have been harmed by overexposure to radiation, please contact us at 1.800.553.8082, or click here for an internet consultation.