About Medical Physics
Medical physics is a branch of physics concerned with the application
of physics to medicine, particularly in the diagnosis and treatment of human
disease. The main areas of interest at present are in the treatment of cancer
by ionizing radiation (radiation oncology), in diagnostic imaging with x
rays, ultrasound and nuclear magnetic resonance (diagnostic radiology),
in diagnostic imaging with radionuclides (nuclear medicine) and in the study
of radiation hazards and radiation protection (health physics).
Other applications of physics to medicine include bioelectrical investigations
of the brain and heart (electroencephalography and electrocardiography),
biomagnetic investigations of the brain (magnetic source scanning), medical
uses of infrared irradiation (thermography), heat for cancer treatment (hyperthermia),
and lasers for surgery (laser surgery).
Areas of activities
Medical physicists are generally involved in four areas of activities:
clinical service and consultation; research and development; teaching,
and administration. Usually a medical physicist is involved in all four areas; the relative
distribution of responsibilities, however, varies considerably from one physicist
to another, depending on the particular situation of the employer as well as on
the educational background and interest of the physicist. Medical physicists
employed in clinics or non-teaching hospitals generally have a heavy service
responsibility, while physicists employed in academic institutions are encouraged
to be involved in academic activities, such as teaching and research. Academic
training alone does not make a medical physicist. In addition, practical experience with
medical problems and equipment is essential, and this may be acquired through
on-the-job training or, preferably, through a structured traineeship (residency) or post-doctoral
program of one or two years in a hospital after graduation with an M.Sc. or Ph.D. degree
in medical physics.
Medical physics organizations
Canada and the United States have a strong tradition in medical physics.
Medical physicists in the two countries can join their national organizations,
the Canadian Organization of Medical Physics (COMP) and the American Association
of Physicists in Medicine (AAPM), which promote
professional activities of medical physicists by publishing journals and
newsletters, and by organizing scientific meetings and special seminars. The International Organization of
Medical Physics (IOMP), formed in 1963, is a scientific, educational, and professional organization of 72
member countries and more than 16000 individual members.
Certification of medical physicists
Several professional organizations, such as the Canadian College
of Physicists in Medicine (CCPM), the American Board of Medical Physics
(ABMP), and the American Board of Radiology (ABR) certify the competence
of medical physicists. The certification
is obtained through passing a rigorous examination and is required for medical
physicists occupying senior positions in the medical environment.
Educational requirements for medical physicists
Since medical physicists occupy a responsible position in the medical
environment, they are required to have a broad background of education and
experience. The requirement for basic education in physics and mathematics
is obvious, but the close working relationship of medical physicists with
physicians and medical scientists also requires some familiarity with basic
medical sciences, such as anatomy, physiology, genetics, and biochemistry.
Currently, the most common path toward a career in medical physics
is progression, through a B.Sc. degree in one of the physical sciences but
preferably in physics, to an M.Sc. degree in medical physics, and then to
a Ph.D. degree in medical physics. The minimum academic requirement for
a medical physicist is an M.Sc. degree in medical physics, and this level
is adequate for physicists who are mainly interested in service responsibilities.
However, medical physicists working in academic environments should possess
a Ph.D. degree in medical physics.
Employment opportunities in medical physics
Medical physicists are usually employed in hospitals and other medical
care facilities. Frequently the hospital is associated with a medical school
and the physicists are members of the academic staff. In many non-teaching
hospitals, physicists hold professional appointments in one of the clinical
departments, and are members of the professional staff of the hospital.
Some of the larger teaching hospitals employ a substantial number of medical
physicists who are organized into medical physics departments. These departments
then provide medical physics services to clinical departments. Medical physics
is a profession in which there is a steadily growing demand for trained
individuals. Most large medical centers now employ physicists and many smaller
hospitals are seeking well trained medical physicists.
It is estimated that there are roughly 5,000 medical physicists practicing
in North America today. More than 1,700 hospitals use radionuclides, and
there are over 2,000 high energy radiation therapy machines in use for cancer
treatment and over 1,200 magnetic resonance imagers in use for diagnostic
imaging.
The manpower needs in medical physics are expected to grow an average
of about 7% per year in the foreseeable future. While radiation therapy
continues to be the major field of employment for medical physicists, new
developments and greater sophistication in equipment and procedures for
diagnostic radiology and nuclear medicine have brought about a substantial
increase in positions available in these two fields.
Medical physics as a career option
A career in medical physics is very rewarding, and the work of medical
physicists is interesting and versatile. Medical physicists apply the principles
of physics toward the diagnosis and treatment of disease, and closely interact
with other health care professionals, such as physicians, biomedical engineers,
and technologists.
A characteristic of modern societies is their ever increasing preoccupation
with health, with health care costs accounting for 10% and 14% of the gross
national product in Canada and the United States, respectively. The research
in cancer and heart disease is growing yearly and many new methods
for diagnosis and therapy are physical in nature, requiring the special
skills of medical physicists not only in research but in the application
to patient care. The employment prospects for newly graduated medical physicists
are excellent. Undergraduate students with a strong background in science
in general and in physics in particular are encouraged to consider seriously
the study of medical physics as a career option.
* Based in part on "The Medical Physicist",
published by the "American Institute of Physics" for the "American
Association of Physicists in Medicine" in 1986.