822. A twitching eye. Acquired Oculomotor Nerve Palsy in a Golden Retriever

"Is the right sunken eyeball present since puppyhood?" I asked the lady owner who showed me a bottle of eyedrops prescribed by Vet 1. No other medication was given by Vet 1 who diagnosed eye infection and advised review if the eye condition did not improve.

Case of the Golden Retriever with a twitching eye
Golden Retriever, Male, 8 years. Weight below normal.
Complaint: Fits 2 days ago. I advised bringing the dog to the Surgery rather than a house-call which would waste money as the dog needed more detailed examination.
History: Right eye is smaller than left eye. Vet 1 prescribed eye drops.

Right eye: Drooping eyelid, retracted eyeball, twitching uncontrollably as if blinking at me when reviewed. Occasional twitching (videoed by Nicole).
3rd eyelid covered the right eyeball partially since it has sunken in.
Hospitalised. Blood and urine tests are minimum tests done.

Lumbar puncture for cerebrospinal fluid analysis, MRI scan of the brain are not done at this stage to lower vet costs.




Oculomotor nerve palsy and brain involvement leading to ptosis & fits





OCULOMOTOR NERVE is the 3rd cranial nerve. It innervates the muscles co controlling eye movements, the upper eyelid muscle and the muscles controlling pupil constriction.

In this dog, the Oculomotor nerve and its branches had been damaged or inflamed causing the eyeball to sink inwards, the eyelid to droop. However, since the dog suffered from fits, the lesion is likely to be inside the brain e.g. brain tumour or aneurysm near the Oculomotor nerve or inflammation.

Blood test - high serum urea
Urine test - proteinuria
Brain scan and lumbar puncture are costly options which need to be discussed with the owner.

Other contributing causes
Trigeminal neuralgia involving only the ophthalmic nerve? The trigeminal nerve has 3 branches - ophthalmic nerve, maxillary nerve and mandibular nerve. There does not appear to be facial spasm or dropped jaw and so, the maxillary and mandibular nerves are not involved. The ophthalmic nerve may be involved.

Diagnosis
Brain scan and lumbar puncture are needed for a definitive diagnosis of acquired Oculomotor nerve palsy in this dog but it is costly.

Treatment
Anti-fits and review. The dog can eat and drink and has no more fits when on anti-fit medication. Steroids were not prescribed. To review.


Updates and more pictures at:
http://www.sinpets.com/dogs/20120115oculomotor-nerve-palsy-golden-retriever-fits-singapore_ToaPayohVets.htm