An ellipse is a set of points, such that for any point of the set, the sum of the distances | |, | | to two fixed points , , the foci, is constant, usually denoted by , > .
Foods to Eat Before a PET Scan. A PET (positron emission tomography) scan is a powerful process for detecting cancer. Cancer cells grow extremely fast and need a lot of glucose. A doctor will inject the patient with glucose, and the PET scanner detects if any cells are emitting signs of high glucose use. If you eat before your PET scan, you risk throwing your glucose levels off balance and getting inaccurate results.
If the biologically active molecule chosen for PET is fludeoxyglucose (FDG), an analogue of glucose, the concentrations of tracer imaged will indicate tissue metabolic activity as it corresponds to the regional glucose uptake.