Positron emission tomography or PET uses sophisticated computer analysis to provide accurate images of the brain. Unlike MRI or CT images, a PET scan provides a detailed image of one's brain function instead of its structure. PET works by injecting radioactive variants of molecules like glucose, oxygen, neurotransmitters, and hormones in the bloodstream to be carried throughout the body. A PET scanner then detects these radioactive molecules that emit radiation, allowing for the study of its uptake and distribution in the brain. In a PET image, the patches where accumulated radiation is highest (active) is typically red and lowest (decreased activity) is usually colored blue.
PET Imaging Used for Diagnosing Memory Disorders
While MRI and CT can give detailed images of the brain's structure, PET imaging are better at detecting functional abnormalities in the brain. Specialists say that it's even possible to detect these abnormalities very early in the course of the disease and before any anatomical changes occur. The decrease or increase in glucose metabolism at a cellular level are said to be the results of disorders that start with functional abnormalities.