PET (positron emission tomography) scan is used to test the functionality of certain organs and tissues in the body, by injecting a radiotracer into the body to create 3-dimensional images. The images are interpreted by the doctor and can help to establish any abnormalities and highlight how well the body is functioning. The procedure is often performed in conjunction with a CT (computerized tomography) scan, in order to get more detailed images and may be referred to as a PET-CT scan. PET scans are commonly performed to diagnose cancer, to determine if the cancer has spread to other organs or tissues, and to monitor cancer's response to treatment. They may also be used to to check the function of the brain, or to help surgeons plan operations such as coronary artery bypass graft surgery, by creating clear images which can help to determine the best method of surgery etc. 

The procedure involves injecting a radiotracer through a vein in the body (IV injection), which contains radiation and makes its way through the blood, building up in the organs and tissues. The PET scanner detects the radiation, creating 3-D images which the doctor can interpret. The results may indicate if an infection is present, if there is a change in organ size, location or shape, if cancer is present or has spread to other organs or tissues, or if there is a problem with the functionality of an organ. 

Recommended for Examining cancer patients Monitoring the progress of cancer patients Patients who are having coronary artery bypass graft surgery Time requirements Number of days in hospital 1 . Patients can usually leave after the procedure and resume activities as normal. Those who are sedated may need to stay for a short time after the procedure, until they recover from the sedation. Average length of stay abroad 1 - 2 days. Number of trips abroad needed 1.