Nuclear Medicine Physicians

Hippocrates, a Greek who lived more than 2,500 years ago, was the first great physician. He is recognized for his theories about the practice of medicine and the anatomy of the human body. His set of medical ethics continues to influence medical practice; the oath that he administered to his disciples is still administered to physicians at the onset of their practice. The "Hippocratic Collection," a collection of around 60 medical texts, are believed to be the first authoritative record of early medical theory and practice. Hippocratic physicians believed in the theory that health was maintained by a proper balance of four "humors" in the body: blood, phlegm, black bile, and yellow bile. Greek physician Galen also influenced medical thought for more than a thousand years. His works were translated into Arabic and Syriac during the Middle Ages.

The great civilizations of Egypt, India, and China all developed medical theories of diagnosis and treatment that influenced later cultures of their own countries and those of other countries. For example, the school of medicine at Alexandria, Egypt, incorporated ancient Greek as well as Egyptian theories, and was influential for several hundred years. Research specialists there learned more about human anatomy than had ever been learned before.

There was no new medical research conducted in the Middle Ages, but monks in monasteries kept the theories and practices of medicine alive by carefully preserving and copying the medical records of the early civilizations. Interest in medical research was revived during the Renaissance. Swiss physician Paracelsus publicly burned the writings of Galen and Avicenna (a Persian physicist and philosopher), signifying a break with the past. Concepts of psychology and psychiatry were introduced by Juan Luis Vives, a Spanish humanist and physician.

Many discoveries and inventions in the 17th and 18th centuries helped to advance medicine. For example, in the 1600s, English physician William Harvey discovered that blood circulates throughout the body, with the pumping action of the heart propelling it. Anton van Leeuwenhoek, a Dutch lens grinder, made instruments that magnified up to 270 times. He also studied blood circulation and composition, and was the first to see bacteria and protozoans. In the 1700s, Dutch physician Hermann Boerhaave introduced clinical instruction (teaching at the bedside of patients). Edward Jenner discovered a vaccination against smallpox. Specialization grew rapidly, as did the growth of medical schools, hospitals, and dispensaries.

More precise instruments, such as the stethoscope, the ophthalmoscope, and X-rays, were introduced in the 1800s. French scientist Henry Becquerel discovered radioactivity in 1896, through his experiments with uranium. Doctors began to use anesthetics like ether and nitrous oxide and antiseptics. Knowledge of the cell, digestion, metabolism, and the vasomotor system increased. Discoveries and developments in the 1900s include the identification of four blood types, the discovery of insulin, development of antibiotics, and immunizations such as the polio vaccine.

Many scientists and inventors have contributed to the field of nuclear medicine throughout the years. In 1929, physicist Ernest Lawrence invented the cyclotron, an apparatus that enabled the study of elementary particles. By the 1950s, the first human imaging of radioisotopes was performed. In 1953, the Society of Nuclear Medicine was founded, and has since been renamed to the Society of Nuclear Medicine and Molecular Imaging. The American Medical Association recognized nuclear medicine as an official medical specialty in 1971, and one year later, the American Board of Nuclear Medicine was established.

Nuclear medicine has grown to be an important component of caring for patients and in conducting medical research. It is also used in pharmaceutical development. Nuclear medicine physicians will continue to be needed to help diagnose, treat, and monitor patients for diseases and disorders.