CT scan's merits weighed against its risks

BLUFFTON -- Recent reports say that CT scans are overused nationwide and could cause cancer in as many as 3 million people over the next three decades.

Computed Tomography (CT) scans superimpose hundreds of X-ray images to make 3-D pictures of the body. In a matter of minutes, they can show doctors what is occurring inside the body without having to cut someone open. They are especially useful in high-trauma situations that require quick decision-making or to find out what is happening to a stroke patient.

The scans, however, expose patients to radiation, which has the potential to cause cancer.

Dr. Robert Hewes of Hilton Head Regional Medical Center said a CT scan is equivalent to one year's exposure of sunlight. The information doctors can obtain from the scans sometimes far outweighs the risks, he said.

The New England Journal of Medicine study, released last month, reports that one-third of CT scans are medically unnecessary.

Hewes said that number is much higher than what he sees locally. Doctors determine what tests are appropriate based on the type of injury or ailment, a person's medical history and physical exam.

"We want to make sure the patients are getting appropriate exams with the least amount of radiation possible," he said. "I have to say, though, that we also need to be careful of the population, especially those people who are young and females."

Women are more vulnerable to radiation, which can lead to an increased risk of still births.

Dr. Joseph Borelli, president of Bluffton's MRI at Belfair and chairman of the national committee on MRI Accreditation, said excessive levels of radiation lead to breaks in a person's DNA, allowing cancer to spread.

He stands by the MRI, which stands for magnetic resonance imaging.

While an MRI takes about 20 minutes, compared to a five-minute CT, it can provide a better picture of the body.

"It picks up more tumors than a CT would," Borelli said. "And, it's better at looking at bone marrow."

Borelli doesn't expect MRI technology to catch up to CT speed. He also says CT scans are more portable and often used for military men and women in times of war.

Other alternatives include:

• X-rays provide one-dimensional views of fractures or broken bones.

• Ultrasound technology uses sound waves to show the structure and movement of the body's internal organs, along with its blood flow. It does not have any negative side effects and is the method of choice for tracking fetal growth and movement.

• A PET scan, or positron emission tomography scan, is a nuclear medicine exam. It carries higher amounts of radiation because a radioactive substance is injected into the body, which causes the person to be radioactive for a few days following the exam.

Source: http://www.beaufortgazette.com/local/story/121710.html