Easy does it before PET scan

By HSC Staff Writer • Published: June 14th, 2006
Category: Health in a Heartbeat

Believe it or not, doctors say the best course of action for patients is sometimes inaction.

While the benefits of regular exercise are fantastic, there are times when strenuous activity should be avoided… and even much less arduous movements like chewing gum.

The hour before a PET scan is one of those times.

PET stands for positron emission tomography, and it’s a way of diagnosing cancers, neurological conditions and cardiovascular disease.

Nuclear technologists inject a patient with a relatively harmless drug, usually a combination of a sugar and a radioactive atom.

The PET scanner can “see” the radioactive material and measure how quickly a patient’s cells take in the sugar. Because dangerous cells such as cancer gobble sugar at a much higher rate than normal cells, doctors can detect problems.

But University of Florida radiologists say people who are about to undergo a PET scan should keep exercise to a minimum in the two days before the test.

That’s because exercise makes normal cells metabolize sugar at a quicker rate, much like problem cells do. Doctors almost always recognize when unusual or excessive physical activity has taken place, but it is distracting.

Likewise, because the tongue is a muscle and speech involves muscular contraction, excessive talking or chewing may cause cellular activity in healthy cells to compete with activity going on in a tumor, potentially “hiding” the tumor.

Figuratively speaking, patients would do well to hold their tongues, especially after the injection.