Description

Molecular imaging is an emerging technology that provides images to visualize specific molecular changes in various diseases in living species. The main tools for scintigraphy are positron emission tomography (PET), single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI). SPECT require a radio-labeled pharmaceutical (radiopharmaceutical) in the diagnosis of many common diseases associated with the malfunctioning of organs as well as in the detection of certain type of cancers. SPECT is a nuclear imaging technique that provides a 3D spatial distribution of single-photon emitting radio nuclides within the body. MRI makes use of the property of nuclear magnetic resonance (NMR) to image nuclei of atoms inside the body. The body is largely composed of water molecules. Each water molecule has two protons. When a person is inside the powerful magnetic field of the scanner, the average magnetic moment of many protons becomes aligned with the direction of the field. The strong expansion of medical MRI has prompted the development of a new class of pharmacological products, called contrast agents.