Expect all healthcare machines to be networked, even if only internally. Need the active directory to login and need to upload the image/test sample somewhere else after it's taken. That's sadly one reason why ransomware can propagate so easily and stop hospitals. :(
In theory there can be computers with no network, typically an isolated computer attached to heavy test machinery, but it's becoming impossibly rare in all industries.
And they should be easy to recognize, look for the post-it nearby with the shared username/password to unlock it, also notice the doctors leaving with the x-ray printed on paper or a USB key to be able to transfer it elsewhere.
This if done is usually against the manufacturer's directives (if even possible to put online).
The equipment that has networking capabilities is designed for internal networks, physically isolated, and it's a big emphasis on this coming from the OEMs.
Changing/maintaining SW in medical devices is not easy (FDA, CE...) and as many mentioned, not everything is designed to move like the web...
People on HN forget that a huge amount of computing has nothing whatsoever to do with the web.