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PET/CT

What is PET/CT?

Positron Emission Tomography, commonly referred to as PET, is an advanced diagnostic procedure that detects changes in cellular function in the body. A CT, sometimes called CAT scan, is an X-ray imaging procedure that produces structural images of your internal organs with greater clarity than conventional X-rays. Together PET and CT can be used to diagnose and manage disease with greater accuracy.

What is a F-18 Fluorodeoxyglucose (FDG) PET/CT Scan?

A FDG PET/CT Scan is a diagnostic procedure which uses a small amount of a tracer (FDG) to help physicians identify abnormal from normal functioning organs and tissues. FDG, when given to a patient, is absorbed by the body's cells. The degree of absorption, shown in a PET/CT scan image, is what helps a physician in identifying areas which may have abnormal cellular activity, possibly indicating disease.

Why is PET/CT important?

One of the reasons that PET/CT can be an important diagnostic tool is its ability to detect changes in a patient's body at a cellular level. For many diseases, including cancer, those cellular changes can occur well in advance of any alteration in anatomy which conventional imaging might identify. That means that PET/CT may detect disease earlier than other imaging methods, when curative therapy can be most effective. PET/CT can also be used to monitor response to therapy and check for recurrent disease.

How is PET/CT used?

PET/CT is utilized in:

  • Oncology to determine the location and severity of a tumor's growth.
  • Neurology to aid in the diagnosis of Alzheimer's Disease, Dementia, brain tumors and seizures.
  • Cardiology to determine the perfusion and viability of the heart.

How do I prepare for my FDG PET Scan?

Preparation for most FDG PET or PET/CT scans include:

  • Fasting for at least 6 hours prior to your appointment
  • Not exercising
  • Arriving on time for the PET/CT procedure

Bring the following with you on the day of your exam:

  • Insurance information
  • Films and reports from previous imaging procedures performed at other institutions.

Wear warm, comfortable clothing without zippers or metallic parts or changing into a gown may be required. You will be asked to remove and store any metal objects that might interfere with scanning. A locker will be available for your valuables and clothing.

If you are scheduled to receive sedation or pain medication, be sure to have someone to drive you home after the exam.

Plan to spend at least two hours at the PET/CT facility.

Exam times and procedures vary with each patient.

Upon arrival at the PET/CT center

Medical history and any prior PET/CT exams will be reviewed. Your Blood Glucose Level (Blood Sugar) will be checked to ensure accurate images are obtained and the injection of the FDG imaging tracer will be administered intravenously (IV).

A brief resting period will be required before the scanning begins. This resting period is necessary for the FDG to be distributed throughout the body.

At the time of FDG PET/CT scanning

  • You will be positioned on the scan table.
  • The table will be moved into a large opening in the scanner.
  • You will be asked to lie still while the scanner acquires the images.
  • The time was the scan varies, but will typically range from 30-60 minutes.

Upon PET/CT scan completion

  • A technologist will process the computer images.
  • The reading physician will interpret these images.
  • A report will be generated and forwarded to your referring physician.
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