Diagnosing 13yo cat

[AlpineMuesli]

13yo boy has been to vets twice in the last month.
At first he just had trouble getting onto bed, coat looking uncared for, visiting food bowl more often, pacing around the house, wheezing. Less friendly, didn’t want affection.
First check vet said maybe arthritis so gave Metacam. Lungs fine, heart fine, but wheezing continued. Medicine didn’t help.
Meanwhile we noticed his pupils were different sizes, and he wasn’t leaving his mat often. Aggression to other cat. Toileting outside fine.
Second check different vet sent off bloods which came back normal. Gave us Zodon antibiotics for his breathing.
He is still wheezing, pacing, all the same but now we see him having little seizures(?) where he rolls over and bats his face, contorting. He’s back on feet after 3 seconds.
Any ideas please?

Doesn't sound goo. My cat was diagnosed with arthritis. But turns out it was something neurological. That caused her to start fitting. Had to have her PTS. Vet thought a tumour.

Thanks for replying, we are expecting the worst after seeing the seizures. We just don’t want him in pain.

It sounds neurological to me - you could push for scans but, being blunt, it depends on your finances and how much stress you're willing to put him through when the diagnosis could be fatal anyway.

If I was fully insured I would probably ask for an MRI but if I wasn't I would be tempted to let him go quietly and quickly.