Medical Services > Radiology Services > Diagnostic Radiology > PET Scan

PET Scan

What is a PET scan?
Positron emission tomography (PET) is a sophisticated imaging technique. It provides information about metabolic activity, how the body's organ systems function and how rapidly cells grow.

Why do I need a PET scan?
PET can clearly identify certain diseases, particularly cancers, often before they are visible on other imaging tests such as CT scans or MRIs.

PET scans are often used to see how well a known disease is responding to treatment such as chemotherapy or radiation.

A PET scan can also be used to study brain and heart function.

What to Expect
A skilled technologist will administer a small intravenous injection of a “tracer” called FDG (fluorodeoxyglucose), which resembles glucose (sugar). The patient will then rest quietly for about one hour as the tracer circulates throughout the patient's body before the scan.

During the scan, the tracer emits a signal, which can be detected by the PET camera. Meanwhile, a computer converts these signals into three-dimensional images of the patient's body. It is important for the patient to remain still as the images are being taken.

A PET scan usually takes about two hours from the time the patient receives the tracer until the scan is completed. The patient will be able to resume normal activities after the test.

Female patients who may be pregnant or are breastfeeding should discuss this with the physician prior to scheduling and with the technologist prior to a PET scan.

PET scans are among Greenwich Hospital's broad range of diagnostic and interventional radiology services.

Radiology services are generally pain-free, non-invasive and available to both outpatients and inpatients.

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