Medical physicists are concerned with the application of physics in medicine to enhance the health care of the community. Medical physicists are primarily concerned with the medical application of radiation to assist doctors in the diagnosis and treatment of patients, that is, they use analytical and applied scientific techniques to assist healthcare workers in the safe diagnosis and treatment of patients.
Medical physicists use a variety of analytical, computer-aided and bioengineering techniques in their work such as radiotherapy, x-ray imaging, ultrasound, tomography, radiology, nuclear magnetic resonance imaging and lasers.
They work both with patients and with a wide range of medical, technical and administrative staff.
There are two kinds of radiation, namely ionising radiation (X-rays, gamma rays, high energy neutrons and electrons) and non-ionising radiation (ultrasound, radio waves, light and magnetic fields).
The most important applications of medical physics are in the following medical disciplines:
Radiotherapy: In radiotherapy, ionising radiations are therapeutically applied to treat malignant conditions such as cancer. Medical physicists are responsible for planning the radiation treatment of the patient and ensuring that the prescribed dose is accurately delivered. They must also ensure that the computerised planning system accurately simulates the radiation distribution that the patient will receive.
Nuclear medicine: Radionuclides are used in nuclear medicine to diagnose diseases. Images of the patient’s organs can be acquired with a computerised scintillation camera after patients have received the required quantities of a specific radionuclide compound. Medical physicists help nuclear medicine physicians to develop techniques, for example for evaluation of the functioning of the heart or kidneys. They try to improve the methods of computer-assisted image processing and are also responsible for the safe handling of radio-pharmaceuticals.
Radiology: Medical physicists are responsible for ensuring that X-ray equipment complies with safety requirements, that optimal exposure techniques are used and that quality control is performed regularly to ensure the best patient care and that patients and radiation workers are exposed to minimal radiation.
Excessive use of, and exposure to radiation is harmful and therefore, sources of radiation and its use are controlled by strict legislation. Medical physicists need to ensure compliance with the requirements that are set by legislation. Research also forms an important part of medical physicists’ work. They may also be expected to train and lecture students in medical and related fields.