Merlin has been diagnosed with CM, and he had a vestibular attack which was caused by PSOM (also known as middle ear disease or glue ear)

They took a sample of the mucus in the middle ear (whilst he was knocked out having the MRI) and sent it to the lab for testing, it came back all clear and no infection was present therefore they decided not to investigate further.

However he has now started to wobble a bit again and his head tilt is starting to come back (and since this happened he shakes him head all the time). He had right side facial paralysis as a result of the middle ear disease which has recified itself (even though the vet said it never would)

My concern now is that they said it wasnt infected, however some symptoms from the PSOM are showing again, so clearly this matter needs to be resolved once and for all.

The vet said the only way to sort it, would be surgery. To cut under Merlins jaw line, enter his middle ear from there, drain and flush the mucus away, and stitch him back up again.
But with Merlin being 7 and a heart condition, i'm worried about putting him through this surgery and the anesthetic.

Surely there are tablets/other options to try before surgery.
Makes me wonder how these symptoms are coming back again even though they claimed it wasnt infected (although in the lab they only had the sample growing for 4 days which I dont think is long enough for a 100% diagnosis)

Any comments would be appreciated.

Gemma and Merlin.