In the pre-DICOM days, I made money by making video capture cards. Back then, the only standard to get images from CT and MRI machines was the composite video

In the pre-DICOM days, I made money by making video capture cards. Back then, the only standard to get images from CT and MRI machines was the composite video on the 75 ohm coax going to the operator's console screen. Laser cameras (medical image film printers) worked the same way. Actually that's not entirely true: there was also a 3M / Kodak defacto standard using a parallel RS-485 bus.