PET scanner is a diagnostic tool that uses a radioactive drug called a tracer, that shows typical and atypical metabolic activity in the body and allows detecting of so called “hot spots”.
PET scan detect diseases before the disease shows up on other tests such as CT or MRI scans alone, being called a “molecular imaging” technique. PET images are usually combined with CT or MRI scan (PET-CT or PET-MRI), in order to detect the exact location of hot spots in the body.
The amount of radiation in the tracer is small, so the risk of negative effects from radiation is low. The most used tracer is FDG (flurodeoxyglucose).
There are at least 3 applications for the PET scan: Oncology, Cardiology and Neurology.
Oncology
On PET scan, the cancer shows up as hot spots because they have higher metabolic rate than normal cells. PET scan is used for an early detection of cancer and it increases the survival rate, if followed by a personalised cancer treatment.
The PET scan is used in: detection of cancer, identifying the spread oc cancer, finding cancer recurrence after treatment and checking if cancer treatment works. The cancers which can be detected through PET scans are: brain, lung, colorectal, pancreatic, head and neck, breast, prostate and lymphoma.
Neurology
PET scan is used in detection of brain tunours, Alzheimer’s disease and seizures.
Cardiology
The main application of cardiac PET/MRI is to detect if there is decreased blood flow in the heart. This is an followed by a decision of recomandation for coronary angioplasty (coronary stent) or surgery (coronary artery bypass).