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CT Scans - Radiation levels prove to be cancer causing

CT image of human head
CT image of human head
courtesy of

Throughout the busy days in many clinics and hospitals, patients are put through the time-consuming process of x-rays and CT (computed tomography) scans to diagnose health issues.  Over the years there has been talk about whether or not they could be potentially harmful or risky, but no definite answers.  However, recent studies show that there is cause for concern over CT scans and the possible threat they may pose to some patients.

CT scans have increased dramatically over the last 20 years. CT scans are also associated with a higher dose of radiation than conventional x-rays. Radiation doses may vary depending on where the CT scans are performed on the human body.  For example, researchers estimate that 1 in every 270 women who undergo CT coronary angiography at age 40 will develop cancer from that scan, compared to 1 in 8,100 women who only had routine head CT scans. The variation of radiation doses also cause the chance of developing cancer to vary.

Investigators at the University of California and their colleagues have conducted studies to estimate the radiation dose and the possible link between CT scans and cancer. The study involved 4 San Francisco Bay Area institutions in 2008.   Findings of the study suggest that radiation doses from common-performed CT scans may be higher than expected. The variability is giving reason for greater standardization of the protocols for CT scans. It also showed that  the same imaging procedure performed on different machines or at different facilities, can yield a significant difference in the amount of radiation - exposing some patients to high risk.  Dr. Rita Redberg of UC San Francisco has acknowledged that these studies make it clear that there is far more radiation from CT scans than previously thought.  To put it in perspective, one CT scan of the chest is like getting 100 chest x-rays, and in some instances the equivalent is even higher: 440 x-rays, depending on the scanner used.

As far as the CT related cancer cases, an estimated two-thirds would be in women, who seem to be far more vulnerable to radiation. Also, the younger the patient is when undergoing a scan, the higher the risk of cancer developing later on in life. Good advice for patients is to keep track of how many scans they have received, and ask for other imaging procedures such as an MRI which minimizes the radiation exposure.