Some of them do run Windows on the console the operator the uses. Some run Linux, and some of the older generation scanners used SGI workstations. They run various RTOS's on the systems that actually control the scanner.
During an operation, one of the OR monitoring devices went down because it was running on Windows and was neglected for some period of time, causing Windows to do an automatic reboot for a "Critical Windows Update."
Of course, seeing a necessary piece of OR equipment go down due to a Windows setting didn't make anyone happy, so the response was to remove automatic update from all of the Windows boxes in the Hospital. Not just mission critical ones, all of them: Secratary's machies, Nurse's machines, IT machines, etc. Fast forwood some months/years, no manual updates were done either, and with automatic ones turned off, a virus came across through a worker's computer and wiped out everything.
True or not, I still think it is a good story for how not to handle security issues.