What does a positron emission tomography scan (PET Scan) visualize?

A positron emission tomography (PET) scan is designed to provide insights into the metabolic processes occurring within the body, particularly in the brain. It visualizes blood flow and glucose metabolism by using a radioactive tracer that emits positrons. When the tracer is injected into the body and taken up by tissues, particularly those with high metabolic activity like active brain regions, it allows for detailed imaging of these areas. As brain cells consume glucose for energy, this process is highlighted on the scan, giving clinicians a view of functional activity rather than just the structural anatomy.

Other methods, such as MRI or CT scans, focus more on the structural components of the brain, while electroencephalograms (EEGs) are used for measuring brain waves and electrical activity. Hormonal changes in the body are typically assessed through blood tests or other specialized imaging techniques that involve different methodologies. Therefore, the focus of a PET scan on visualizing blood flow and glucose activity distinguishes it as a critical tool for understanding brain function in various medical contexts.