PET Scan

A Positron Emission Tomography (PET) scan is a highly advanced nuclear medicine imaging technique that allows doctors to observe metabolic and physiological activity within the body at the cellular level. Unlike standard imaging tests such as CT or MRI, which reveal the structure of organs, a PET scan shows how tissues and organs are functioning, often identifying diseases before structural changes appear.

What Symptoms or Conditions May Lead to a PET Scan?

A PET scan is usually recommended when patients experience symptoms that may indicate:

• Persistent unexplained weight loss

• Chronic fatigue

• Seizures or neurological deficits

• Persistent pain with no clear structural cause

• Signs of cancer recurrence or metastasis

• Abnormal blood work or tumor markers

What Causes or Conditions Does PET Help Diagnose?

PET scans are highly effective in diagnosing or monitoring:

• Cancer: Detecting tumors, metastasis, or monitoring treatment response

• Neurological disorders: Alzheimer’s disease, Parkinson’s disease, epilepsy

• Cardiac conditions: Identifying areas of poor blood flow or damaged heart muscle

• Inflammatory and infectious diseases: Sarcoidosis, certain infections

Treatment Planning and Monitoring

A PET scan is not just diagnostic—it plays a key role in:

• Staging cancer before initiating treatment

• Monitoring how well chemotherapy or radiation is working

• Assessing surgical viability, especially in the brain or lungs

• Determining brain function before epilepsy surgery

• Evaluating cardiac viability for bypass surgery decisions

How Is the PET Scan Performed?

• A small amount of radioactive tracer (commonly FDG – a form of glucose) is injected into the bloodstream.

• The scanner detects areas of high tracer uptake—these usually indicate high metabolic activity (as seen in cancer cells).

• The entire procedure is non-invasive, painless, and usually takes 30–60 minutes.

Key Advantages

• Detects diseases before structural changes occur

• Can differentiate between benign and malignant tumors

• Assists in personalizing treatment plans

• Often combined with CT or MRI (PET/CT or PET/MRI) for comprehensive imaging