Questions about the overuse and true necessity of CT reflect a growing awareness of the potential pitfalls of diagnostic imaging, which in the past two decades has exploded into a $100 billion-a-year business.
Like x-rays and PET, CT uses ionizing radiation, which can damage DNA and cause cancer. Two other imaging technologies, MRI and ultrasound, do not use radiation. Computerized tomography is used for a plethora of reasons: evaluating chest, back and abdominal pain as well as headache.