When was PET invented?

The concept of emission and transmission PET (positron emmision tomography) was introduced by David E. Kuhl and Roy Edwards in the late 1950s.

However, in 1961, James Robertson and his associates at Brookhaven National Laboratory built the first single-plane PET scan, nicknamed the "head-shrinker.

The PET compound was first administered to two normal human volunteers by Abbas Alawi in August 1976 at the University of Pennsylvania.

The PET/CT scanner, attributed to Dr David Townsend and Dr Nutt was named by TIME Magazine as the medical invention of the year in 2000.

source: wikipedia and others