Mayo Clinic neuro-radiologists were enthusiastic after seeing the first images from Geoffrey Hounsfield’s prototype computed tomography (CT) scanner (made by the EMI organization in England) in the spring of 1972. One of them, Bud Baker, went to England in the summer of 1973 to learn more about the machine, with permission from the Mayo Clinic Board of Governors to buy a machine ″on the spot″ if he saw fit (a little unusual because CTs cost about $350,000 at the time, enough to outfit several labs). He promptly made an offer on an EMI scanner. The National Hospital at Queen’s Square had already ordered the first non-prototype machine but the hospital was 150 years old and the floors and elevators couldn’t support the machine’s weight. It would take two years for them to refurbish the hospital to accomodate the scanner. Thus the Mayo Clinic obtained the first EMI CT scanner outside the United Kingdom. EMI asked Baker how many machines he thought would sell in the U.S. He guessed 3,000. ″That kind of flabbergasted them. They didn’t really know what they had,″ Baker said. This number was quickly surpassed as the CT scanner proved its revolutionary utility for central nervous system diagnosis.

Submitted by Jacqueline A. Leavitt from the Cogan Ophthalmic History Society.