My plan was to start a non-profit organization and hire some radiologists, AI experts, and software engineers. I would also need a lot of help from lawyers and healthcare experts to make sure we're complying with laws and regulations. Then I wanted to purchase a few second-hand MRI machines and start a pilot program somewhere.
I would probably start in New Zealand (my home country), and then move to other countries with universal healthcare (Australia, Canada, UK.) Early detection of cancer should end up saving a lot of money (compared to treating cancer in the later stages), so in the future it should be possible to get government funding that covers the entire program.
I'm not too interested in starting a for-profit company, but it's probably the only way to do something in the US. So I'd leave that to someone else.
But yes, it definitely makes sense to work with a university or hospital. Maybe the Centre for Advanced MRI at Auckland University [1].
(P.S. This is just a project I would want to tackle if I ever sell a company and end up with a ton of money. There's no chance that I'll be doing something soon.)