Allan Cormack American physicist Date of Birth: 23.02.1924 Country: USA

1. Early Life and Education
2. Research and Development of Computed Tomography
3. Mathematical Methods and Experiments
4. Recognition and Collaboration
5. Nobel Prize and Later Career

Early Life and Education

Allan McLeod Cormack was born in Johannesburg, South Africa, on February 23, 1924. His parents, George Cormack and Amelia Cormack (née McLeod), emigrated to South Africa from Scotland before World War I. When Cormack was twelve years old, his father died, and the family moved to Cape Town, where he enrolled in the South African College Boys' High School.

Cormack excelled in physics, mathematics, and astronomy. He graduated from the University of Cape Town in 1944 with a bachelor's degree and in 1945 with a master's degree in physics. In 1950, he married Barbara Seavey. The couple had one son and two daughters.

Research and Development of Computed Tomography

Cormack's scientific curiosity led him to pursue doctoral studies at the Cavendish Laboratory of the University of Cambridge. While there, he conducted research on the properties of radioactive helium under the guidance of Otto Frisch. In 1956, Cormack accepted a teaching position at the University of Cape Town, where he became intrigued by the clinical applications of radioactive isotopes.

Observing the shortcomings of conventional X-ray imaging for treating cancer patients, Cormack conceived the idea of using multiple X-ray measurements to obtain more accurate information about the absorption of radiation by different tissues. This concept laid the foundation for computer tomography (CT), a revolutionary medical imaging technique.

Mathematical Methods and Experiments

Cormack developed mathematical methods for analyzing the X-ray data and spent several years refining his approach. In 1956, he conducted experiments using a cobalt-60 gamma-ray source and a human body phantom to further test his theory. The results confirmed his hypothesis and demonstrated the potential of CT in visualizing internal body structures.

Recognition and Collaboration

Cormack's research gained momentum in the 1960s. In 1963 and 1964, he published articles on his mathematical methods and experimental findings, but they received little attention. Meanwhile, in England, Godfrey Hounsfield, an engineer and scientist at EMI, independently developed a similar approach to CT using modern computers.

In 1971, the first clinical CT scanner was installed at Atkinson Morley Hospital in Wimbledon, England. The results were groundbreaking, demonstrating the superiority of CT over conventional X-ray imaging. In 1972, EMI released the EMICT-1000, the first commercial CT scanner.

Nobel Prize and Later Career

In 1979, Cormack and Hounsfield were jointly awarded the Nobel Prize in Physiology or Medicine "for the development of computer-assisted tomography." Cormack's Nobel lecture highlighted the motivations behind his work and emphasized the importance of using advanced techniques to improve patient care.

After becoming an American citizen in 1966, Cormack held various academic positions at Tufts University in Medford, Massachusetts. He became the university's first University Professor in 1980 and received an honorary doctorate that same year. Cormack remained active in scientific research and served as an associate editor of the Journal of Computed Tomography. He died in 1998, leaving behind a legacy of innovation and contributions to the field of medical imaging.