Mary Kathryn Lynch stood next to her young son in a Lake Tahoe emergency room. The Oakland resident had rushed her 9-year-old to the hospital after a ski accident left him groggy, curled up in the fetal position, and speaking incoherently.
Nurses and hospital staff told Lynch that her son needed a CT scan of his head right away, she recalled.
While Lynch and her husband were both worried the accident may have caused brain damage, her husband was also weighing risks of the scan’s radiation.
CT — or computerized tomography — combines a series of x-rays for a sophisticated image. In this case, doctors could use the scan to quickly detect internal bleeding or other injuries.
It is a powerful tool that has saved lives by discovering small problems before they’ve had the chance to get worse, says Andrew Phelps, a pediatric radiologist at UCSF. But the useful pictures come at a cost: CT scans expose patients to radiation levels that are higher than other types of imaging, like traditional x-rays or MRIs.
And exposure to high levels of radiation has been linked to cancer. Continue reading