A PET/CT scan is a medical imaging technique that merges positron emission tomography (PET) and computed tomography (CT) into a single session. PET uses a small amount of radioactive material called a radiotracer to measure cellular activity, such as metabolism, while CT provides detailed anatomical images of the body’s structures. The combined images allow doctors to pinpoint abnormal metabolic activity with precise anatomical location, improving diagnostic accuracy compared to either scan alone .

During a PET scan, a radiotracer is injected into the bloodstream. Cells that are more metabolically active, such as cancer cells, absorb more of the tracer, creating “hot spots” visible on the scan. The CT scan then provides detailed images of the body’s organs and tissues, which are overlaid with the PET images to create a co-registered image.

PET/CT scans are used to:

• Detect and stage cancer, including identifying metastases and monitoring treatment response

• Evaluate heart conditions, such as areas affected by a heart attack or regions that may benefit from surgery

• Assess brain disorders, including tumors, memory disorders, and seizures

• Monitor treatment effectiveness and detect disease recurrence

• Map normal brain and heart function for research or clinical purposes