When Is a PET Scan Used?

The primary purpose is to detect cancer and monitor its progression, response to treatment, and detect metastases (cancer spreading to different body parts). Cancer cells show bright spots on PET scans as they have a higher metabolic rate than normal cells.

PET scans can also help plan operations such as brain surgery for epilepsy or coronary artery bypass graft. They can help diagnose dementia as it shows the changes in brain functions.