We developed simple test tools to optimize imaging parameters. No company was interested in our idea.
When I entered medical physics in 1958 there were fewer than 100 in the U.S. and I could see many opportunities to apply my knowledge of nuclear physics.
Nuclear physics is interesting but it is unlikely to help society.
In 1970 I realized that there was negligible risk from x-rays but many radiographs had poor image quality so that the risk from a false negative was significant.
In some cases radiation reduces the incidence of cancer.
Many Nobel Prizes are awaiting good research to understand and explain the many mysteries of our bodies, such as the basic mechanism of memory or imagination.