Thank you for all the information . It was very helpful.
I don't know how long the swelling will be there. The docs can do a CT scan of his brain, those are simply high-powered special X-rays that do not react badly to metal the way magnetic MRIs do, and it may show if there is any problem in the brain itself. A neurologist should evaluate those scans and do a few neuro tests on your sleeping friend, like shining a light in his eyes, simple things like that. Also, the docs should make sure he doesn't have any infection going on, and of course keep an eye on the swelling situation. They are probably also giving him steroids via I.V. to keep the swelling down, in addition to the shot they gave him. I assume the cervical fusion was higher up, any operation there is a serious matter, so once he had this swelling problem, he should have been put in an ICU. An EEG can be done on him, to see if he's got normal electrical currents going on in the brain, too, and it would detect any decline thereof also.