Trigeminal Neuritis in Cats
Trigeminal nerve neuritis (inflammation) is characterized by the sudden onset of the inability to close the jaw owing to dysfunction of the mandibular (jaw) branch of the trigeminal nerves (one of the cranial nerves). This may be due to nerve injury, which ranges from neuritis, demyelination (loss of the fatty sheath around the nerve which helps conduct the signal), and sometimes to fiber degeneration of all the branches of the trigeminal nerve and the nerve cell body.
This condition is uncommon in cats when compared to dogs.
Symptoms and Types
- Acute onset of a dropped jaw
- Inability to close the mouth
- Drooling
- Difficulty in getting food in the mouth
- Messy eating
- No loss of feeling in the jaw or face
- Swallowing remains normal
Causes
The underlying cause of trigeminal nerve neuritis is currently uknown, though it is possibly immune-mediated.
Diagnosis
Your veterinarian will perform a thorough physical exam on your cat, taking into account the background medical history, onset of symptoms and possible incidents that might have led to this condition. Your veterinarian will order a blood chemical profile, a complete blood count, a urinalysis and an electrolyte panel to rule out other diseases. Rabies is one of the more important disease conditions that will need to be ruled out. Diagnostic imaging like X-ray will be used to examine the skull and jaw bones, and bone marrow core biopsies and muscle biopsies can be used to rule out other possibilities for disease.
Treatment
The most effective treatment is supportive care. Your cat will need assistance with eating and drinking. If you are able to provide sufficient care at home, your cat may be treated as an outpatient, but if you cannot care for your cat, it will need supportive nutritional care in the veterinary hospital so that it is receiving adequate nutrients.
If your cat is still able to lap and swallow food that is offered, you can use a large syringe that is placed in the corner of the mouth to feed the cat water and pureed foods, with the cat's head slightly elevated so that it can swallow easily. Fluids can also be administered subcutaneously (under the skin). Feeding tubes are rarely necessary for maintaining adequate food intake, but may be used if your cat is unable to take anything into the mouth or swallow the food that is given.
Living and Management
This disease usually spontaneously resolves after two to four weeks. One result of this disease is shrinkage of the muscles used for chewing. Once the condition has stabilized and your cat is able to move its jaws normally again, you can help your cat to rebuild the jaw muscles. Your veterinarian will recommend exercises for doing this based on your cat's overall health and age.