Good questions, and I don't claim to fully know the answers. Some such software is released open-source, e.g. NifTK, FSL, MedINRIA. Some is spun out and then s

Good questions, and I don't claim to fully know the answers. Some such software is released open-source, e.g. NifTK, FSL, MedINRIA. Some is spun out and then sold through vendors as a service, e.g. Siemens, icoMetrix, many others. Why aren't things used more? I'd say the main bottlenecks are monetary, political and cultural. Doctors are often set in their ways, and hospital management staff are risk-averse. Moreover, because of legal liability issues, a lot of this stuff has not been formally approved for clinical use -- so hospitals won't touch it. This is especially true of the open-source software. Getting approved is an expensive and time-consuming process. Service contracts with approved software are expensive, mostly as a result of this. Heck, look at the struggle involved in digital patient records, which is supposedly a simpler problem than imaging. In the UK, we've spent billions on that without getting anything usable. There are uniquely bad political reasons for that, but it's illustrative nonetheless.