Ligaments attach your breasts to the pectoral muscle on your chest. When you wear a bra, your supported breast does not allow the pectoral muscle to be exercised as much as it could be. When you do not wear a bra, as you move your arms, reach, and lift, your pectoral muscle is strengthened.
Positron emission tomography. Positron emission tomography (PET) is a nuclear medicine functional imaging technique that is used to observe metabolic processes in the body. The system detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide (tracer), which is introduced into the body on a biologically active molecule.
Advanced Search. A positron emission tomography (PET) scan is a unique type of imaging test that helps doctors see how the organs and tissues inside your body are actually functioning.The test involves injecting a very small dose of a radioactive chemical, called a radiotracer, into the vein of your arm.ne of the main differences between PET scans and other imaging tests like CT scan or magnetic resonance imaging (MRI) is that the PET scan reveals the cellular level metabolic changes occurring in an organ or tissue.