Otitis media

Lend me your ears!

Otitis media is the inflammation of tympanic membrane, bony acoustic duct and tympanic cavity. Otitis media can occur in rabbits by direct spread of bacteria from Otitis externa, or indirect haematogenous spread.

Clinical signs of Otitis media may include:

The main differential diagnosis is Encephalitozoon cuniculi (EC / E.cuniculi), which is can be ruled out with serological tests, like IFAT or ELISA tests, the best is the PCR test (last checked not available in Australia).

Other differentials include:

Pain relief may be required, this can be supplied with either:

Vestibular signs can be quite serious and potentially can cause severe trauma in rabbits, falling over and rolling around. It is important to manage the environment when you see vestibular signs, removing sharp objects and providing tons of padding (think towels!).

Antibiotics:

The bacteria involved in Otitis in rabbits are:

Therefore a good broad spectrum antibiotic is required for treatment, usually for 4 weeks or more of therapy:

For doses, check out our rabbit formulary for vets at exoticsvets.com/rabbit-formulary/

You will need a password, and to be a vet! If you need the password, email us at exoticsvets@gmail.com

But as with otitis externa, the best chance of recovery often includes surgery:

Surgery:

Disclaimer: These are the surgical options, which should only be performed by experienced surgeons or rabbit veterinarians!!!

But here’s a brief description so you know what to tell your clients, to provide them with the very BEST for their bunny. For an in depth description, check out “Surgical Management of Ear Diseases in Rabbits” by Csomos R et al – reference is in the references!

Here are simple descriptions of VERY COMPLICATED surgeries that should ONLY BE PERFORMED BY EXPERIENCED SURGEONS AND RABBIT VETERINARIANS!

Ear canal ablations:

An incision is made vertically over the ear canal, the ear canal is isolated by dissection, then cut between the opening and the bony acoustic meatus – then lavaged sutured and closed routinely.

An incision is made as a T shape over the ear canal, the ear canal is isolated by dissection, then cut above the bony acoustic meatus and all cartilage is removed – then lavaged sutured and closed routinely.

REMEMBER – PAIN RELIEF IS CRITICAL IN RABBITS!!!!!!!!!!!!

Bulla Osteotomy –

Usually following either ear canal ablation technique, the soft tissues over the bony acoustic meatus are elevated, then the osteotomy is performed into the tympanic bulla. Once open – curette and lavage to remove debris, followed by routine closure.

With the rabbit in dorsal recumbency, dissect and retract muscles until the bulla is exposed. The osteotomy is performed into the tympanic bulla. Once open – curette and lavage to remove debris, followed by a routine closure.

Yes these descriptions are kept purposely quite simplified, if you are a veterinarian with access the Csomos reference, the details can be acquired.

Or, do the best thing, refer the rabbit to an experienced surgeon!

If you are presented with a rabbit with Otitis, do your best to provide analgesia, keeping your bunny patient comfortable, and treat the source of the infection!

If you are unable to resolve the otitis medically, or if the infection is too chronic, then referral for surgery is your bunny’s best option!

Hop to it!