Photo of Robert Ledley

Robert Ledley

  • National Medal of Technology and Innovation
  • Medicine

For pioneering contributions to biomedical computing and engineering, including inventing the whole-body CT scanner which revolutionized the practice of radiology, and for his role in developing automated chromosome analysis for prenatal diagnosis of birth defects.

Robert S. Ledley wanted a career in physics. His family, concerned that might not be sufficient to pay his bills, pushed instead for him to become a dentist. A compromise was struck: Ledley could study physics as long as he also became a dentist.

Dr. Ledley did indeed become a dentist. But physics and technology is where he made his indelible mark: He is credited with inventing the first full-body CT scanner in 1973, which provided doctors a powerful new diagnostic tool that saved countless lives.

A prolific author and researcher, Dr. Ledley received a doctor of dental surgery degree from New York University in 1948 and a master’s degree in physics from Columbia University in 1950. After serving time in the Army Dental Corps during the Korean War, Dr. Ledley taught electrical engineering at George Washington University and later founded the National Biomedical Research Foundation.

In 1974, after his invention of the CT scanner, Dr. Ledley started the Digital Information Science Corp., known as Disco, which marketed the scanners. Dr. Ledley’s prototype is housed in the Smithsonian’s National Museum of American History. He later sold his company to Pfizer.

Dr. Ledley also taught at Johns Hopkins University and Georgetown. He was inducted into the National Inventors Hall of Fame in 1990.

By Robert Warren