Godfrey Hounsfield

Sir Godfrey Hounsfield (b. 28 Aug 1919, d. 12 Aug 2004) pioneered the CT scanner making him one of the greats in the history of radiology. For his work, he received the Nobel Prize in Stockholm in 1979. This was remarkable because Godfrey had no previous experience of working in the medical field but was an engineer who had spent his working life, prior to x-ray scanners, developing computers and radar. 

Godfrey ushered in a new era of medical imaging when he published the first clinical CT scans. Many previous medical tests were made obsolete by his innovation, including painful and invasive procedures, such as pneumoencephalography and contrast encephalography. His method was fast, pain-free, and made the most efficient use of the allowable X-ray dose. Over 40 years on from his great breakthrough, CT scanners are still in use all around the world, and millions of people have benefited from better diagnosis. Modern scanners have few features which were not first envisaged by Godfrey in 1968 1.

His life provides an insight into the way in which inventions grow from initial conception to becoming a reality through the sheer perseverance and determination of one remarkable individual. 

Godfrey grew up on a small farm near Newark, UK 2 . He left school at age 16 with no qualifications. His school record card discusses his “intellectual retardation”, and he did not study at a university. So his early years did little to suggest that he would pioneer such a great medical breakthrough or be awarded the highest honour in science. 

He volunteered for the Royal Air Force in October 1939, and his wartime years, during which he became a radar instructor, were a major turning point. After the war, Air Vice-Marshal Cassidy helped Godfrey to get a grant to study at Faraday House college, which gave him a diploma. The course was mostly on electric motor design, with little maths beyond school-level, but it was useful when seeking a civilian job. He joined the EMI company, where he worked on radar and computers until 1967. He led the design team for the EMIDEC 1100 computer which was successfully launched in 1957, mostly using skills which he had taught himself or learnt in the RAF. 

 In 1967 Godfrey’s previous projects ceased to be of interest to EMI because of changes in company strategy. He was asked to suggest a new line of work involving pattern recognition, and he suggested what eventually became CT scanning. EMI was unenthusiastic because they had no significant medical business, Godfrey had no medical knowledge, and his proposal was a high-risk leap beyond existing technology. So they sought external funding, and Godfrey managed to get a small amount of money from the Department of Health and Social Security. His struggles for funding continued for the next four years, and he also had to struggle against adverse market research. Visits to the radiology experts at the leading hospitals found that almost everyone (with notable exceptions James Ambrose, Louis Kreel, Evan Lennon and Frank Doyle) thought that his proposal was pointless. Everything changed after the first publication of his clinical CT scans at conferences in London in April 1972 and in New York in May 1972. As soon as people saw those CT scans, they realised how valuable they were. He was the first to show discrimination between soft tissues, tumours and blood clots in clinical use at acceptable cost and dose. Godfrey was inundated with orders for scanners and received a knighthood and dozens of academic awards. However, it had been a long and difficult road to reach that point. His life would have been easier if he had chosen a project which optimised technology which his employer was interested in, rather than revolutionising a field which was new to him and to his company. He persevered because he knew that he was on the track of a hundred-fold improvement, and that vision drove him on. 

Godfrey thought in an unusual way which he described as “you’ve just got to use the absolute minimum of maths but have a tremendous lot of intuition” 3.This is easy to say, but very hard to get right. He used a lot of pictures and mental models, a lot of analogies, and he had a lot of curiosity about how everything in the world worked. This was uncomfortable for academics. How could this highly mathematical field be opened up by someone who was not an academic, not a mathematician, but a man who used the subversive art of intuition? Godfrey’s answer would probably have been that he worked it out from first principles. 

Sir Godfrey Hounsfield rarely used his title, preferring to be called Godfrey. He was gentle, generous, modest and unambitious, but doggedly persistent in his work. He liked working in small teams, but he was always slightly outside the formal structure—a man who set his own rules. Although some people of his seniority rarely talked to those beneath them, he would talk to anybody who was interested in his work, whether it was the cleaner, the panel-beater or the managing director. He was sociable: people who met him socially would see him as an amiable person who helped to wash up the coffee cups, and he’d prefer not to tell them of his past achievements. His focus was the future.

From his teenage years onwards he was interested in how things worked, and in how science and engineering could help to improve the world. He wanted to pass this enthusiasm on to the next generation. Although he dreaded public speaking, he agreed to speak to pupils at his former school. He wanted to tell them that “each new discovery brings with it the seeds of other, future, inventions. There are many discoveries, probably just around the corner, waiting for someone to bring them to life. Could this possibly be you?” 4. What an inspirational message!

This article is based, with permission, on a biography 1 which clarifies some misunderstandings. For example, Godfrey joined EMI in 1949 (not 1951), his studies at Faraday House did not reach university level and the development of CT was not linked to The Beatles. He worked on CT from first principles, independently of predecessors (such as J.Radon, G.Frank, C.Tetel’Baum, R.Bracewell, W.Oldendorf, D.Kuhl, and A.Cormack). Godfrey’s debt was to others: a physics teacher called Mr Ashton, the RAF and John Cassidy, and Alan Blumlein.

History of Radiology
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Section: Physics
Tag: history
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