Radiation from CT scans may be linked to cancer and more deaths, according to studies published in the Archives of Internal Medicine.

CT scans are a special type of x-ray called a computed tomography. Experts say those scans have a higher radiation dose than conventional x-rays and expose people to four times as much radiation than previously thought.

It is estimated that scans done in 2007 will cause 29,000 deaths and kill nearly 15,000 Americans.