This sounds like vestibular disease which can be due to an inner ear problem or a neurological issue. You can read about this here.
http://marvistavet.net/html/body_vestibular_disease.html
If the CT scan did not include the bulla (inner ear) as a focus x-rays of that area might give you information on needed care.
This is more technical but becomes more readable down the page
http://www.vcsmilford.com/vs.html
Unfortunately the answer is maybe he can recover depending on where and what the problem is triggering this. I have had several senior rescues with this problem who ended up with a head tilt but recovered. I had one that nothing could help and we later found it was a brain tumor.
If you have not seen a veterinary neurologist (and based on the CT scan you may have) that would be one avenue to pursue. This site lets you search for vets with that specialty
http://www.acvim.org/Specialist/Search.aspx
If that step has been taken then you may want to try a different direction and see if a holistic care option might work. This site may help you find a holistic vet to work with
http://www.holisticvetlist.com/#search
Accupuncture might help for example.
Good luck with the little guy!
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