In hospitals you have probably seen patients undergoing radiation therapy for cancer. It is a part of medical specialty called "Nuclear Medicine". Nuclear medicine uses radioactive substances to image the body and tear diseases.
Nuclear medicines is used mainly to allow visualization of organs and regions within organs that cannot be seen on conventional X-Ray images. In an X-Ray or CT examinations,the radiation comes out of the X-Ray or CT system and then passes through the patient's body before being detected and recorded onto film or by a computer. Nuclear medicines uses the opposite approach; a radioactive material is introduced into the patient,and is then detected by a machine called a gamma camera. The radiation which is emitted by the body during nuclear medicine imaging are gamma rays. These gamma rays are similar to X-Rays but with a shorter wave length.
The radioactive substances used in the nuclear medicine imaging consists of pharmaceuticals that have been labeled or tagged with radioactive element(radioactive elements emit certain invisible radiation spontaneously). In diagnosis, radioactive substances (or,radio pharmaceuticals) are administered to patients and the radiation emitted is measured. In therapy radiopharmaceuticials are administered to treat disease. Very small amount of radioactive materials are introduced into the body. The levels of radiation involved in nuclear medicine studies is usually considerably lower or equal than a patient would receive in a conventional X-Ray stud or CT Scan. Whole body and healthy doses can be minimized while the radioscope is targeted only towards the affected tissue or organ.
Nuclear medicine imaging or scanning shows not only the anatomy(structure)of an organ or body part,but the function of the organs as well which shows whether the organ is working properly or not. This is due to the fact that the radioactive substances are absorbed by or taken up at varying rates(or in different concentrations)by different tissues type. For instance,the thyroid gland takes up more radioactive iodine than other parts of the body. The amount of radiation that is taken up and then emitted by a specific body part is linked to the metabolic activity on a nuclear medicine image etc.
Nuclear medicine can image and or show the function of a variety of organs and body parts to diagnose a number of medical conditions including abdomen, brain, blood, hepatobiliary system(gall bladder and the bile duct) heart, kidneys, liver/spleen, lung, stomach and thyroid.
Although nuclear medicine is commonly used for diagnostic purposes, it is also used to provide valuable therapeutic applications. Among these therapeutic uses are-treatment of hyper thyroidism, treatment of thyroid, cancer, prostate cancer, cancer bone pain and polycythemia (abnormal increase in red blood cells).
Nuclear medicine is now an integral part of patient care and is extremely valuable in the early diagnosis, treatment and prevention of numerous medical conditions. Thus radiation helps doctors see deeper inside the human body than they ever could.
