What is the role of nuclear medicine in diagnosis of diseases?
Diagnostic nuclear medicine involves the use of isotopes of elements like technetium, iodine, thallium, gallium and indium for imaging. These are unstable forms of matter that emit electromagnetic radiation in the form of gamma rays, which are detected by instruments called gamma cameras. Different isotopes are attached to chemicals specially designed to target the specific organs to be imaged, to form radiopharmaceuticals, which are then introduced into the body by intravenous or subcutaneous injection, orally (as solid or liquid), or inhaled as a gas or aerosol. Disease processes are identified by a change in the normal distribution pattern of the radiopharmaceutical within the body, displayed as coloured images on computer screens. Radioisotope imaging or scintigraphy differs from plain X-rays, ultrasound, CT or MRI. Conventional radiological techniques demonstrate structural changes in organs or tissues resulting from the disease. Scintigraphy detects pathological changes in organ
