What is Biomedical Physics?

Radiation Therapy is involved with the use of radiation (mainly gamma and x-rays) for the treatment of malignant tumors. The medical physicist plays a pivotal role in ensuring that the right radiation dose is delivered to the patient. There have been several recent technological developments in the field such as 3D conformal radiation therapy and intensity modulated radiation therapy (IMRT).

IMRT is designed to address a major limitation of conventionally delivered radiotherapy: its inability to restrict the treatment beam to the tumor-bearing tissue. Unlike conventional treatment, with IMRT, the intensity of radiation is made to vary across the beam. Inverse planning algorithms are used to determine optimal intensity-modulation. A dynamic multileaf collimator is used to sweep opposing pairs of tungsten leaves across the field.

In 3D conformal radiation therapy, the prescribed dose is shaped to match the 3D target volume of cancer cells. Computers are also used to generate beam’s eye-view (BEV) images that present a patient’s anatomy as it would appear to a viewer located at the radiation source. BEV images are used to aid in determining which x-ray beam orientation would yield the best view of cancer cells without irradiating too much normal tissue.

Nuclear Medicine involves the use of radiopharmaceuticals to diagnose and treat diseases. Nuclear Medicine Imaging is unique because it provides physicians with information about both structure and biological changes. These studies have several applications in neurology, cardiology, oncology, etc. The Society of Nuclear Medicine estimates 16 million nuclear medicine imaging and therapeutic procedures are performed each year in the US.

Positron-Emission Tomography (PET) is one such imaging modality in nuclear medicine that has delivered the promise of revealing the presence and mechanism of diseases such as cancer, heart disease, and brain disorders like Parkinson’s and Alzheimer’s disease.

X-rays have given us an extraordinary tool to enhance our ability to see inside the human body. It has been truly Medicine's New Vision from the first radiograph of Röntgen's hand.

Magnetic Resonance Imaging (MRI) is a non-invasive imaging technology that produces three dimensional detailed anatomical images. It is often used for disease detection, diagnosis, and treatment monitoring. It is based on sophisticated technology that excites and detects the change in the direction of the rotational axis of protons found in the water that makes up living tissues.

"Health physics" is the profession devoted to protecting people and their environment from potential radiation hazards, while making it possible to enjoy the benefits of the peaceful use of the atom.

Health physicists work in a variety of disciplines, including research, industry, education, environmental protection, and enforcement of government regulations.

Medical Health Physicists work wherever radiation sources are used to diagnose and treat human diseases. Hospitals, clinics, and major medical centers use radiation sources, including x-ray machines, particle accelerators, and many types of radioactive materials. Medical health physicists are needed to ensure proper and safe working conditions for both patients and medical staff.

A medical health physicist often serves as the designated radiation safety officer (RSO) for a medical facility. The RSO is responsible for performing radiation safety surveys of all radiation sources used within the facility; monitoring radiation exposure of workers, patients, and visitors to the facility; establishing and monitoring radiation safety procedures; and assuring the medical facility is in compliance with state and federal radiation safety regulations..