Trigeminal neuritis is a rare neurological disease of dogs characterized by inflammatory disease of cranial nerve V (trigeminal nerve) with subsequent jaw paralysis. This disease is usually of idiopathic origins and can affect any breed of dog. Dogs with trigeminal neuralgia often have trouble blinking their eyes and opening and closing their mouths. Clinically affected dogs present with polydipsia, trismus, ptyalism and mild dysphagia, although some dogs are usually able to swallow normally.
The primary symptom of trigeminal neuralgia is an inability to open and close the mouth. He may lose the ability to blink his eyes. In most cases, dogs don’t experience total paralysis of the facial muscles, especially not in the initial stages of the disease.
- Inability to close mouth
- Acute onset of dropped jaw
- Messy eating
- Swallowing remains normal
- Difficulty in getting food in the mouth
Sometimes, trigeminal neuralgia occurs in dogs without an obvious reason. This type of trigeminal neuralgia is known to vets as idiopathic trigeminal neuralgia. Trigeminal neuralgia in dogs typically occurs due to injury or inflammation of the trigeminal nerve. Bone deformities, tumors, and injuries can cause trigeminal neuralgia in dogs.
Diagnosis is usually based on presenting clinical signs and exclusion of other causes. Muscle biopsies are usually definitive and show nonsuppurative inflammation and demyelination in the motor branches of the trigeminal nerve involving demyelination with some axonal loss.
A differential diagnosis would include Clostridium tetani, rabies, temporomandibular joint ankylosis due to fractures, masticatory muscle myositis, peripheral nerve sheath tumor, polymyositis, mandibular osteosarcoma, trigeminal nerve paralysis and central neurological lesions, temporomandibular joint luxation and dysplasia, temporomandibular osteoarthritis, retrobulbar abscess and severe otitis externa.
The most effective treatment is supportive care. Your dog will need assistance with eating and drinking. If you are able to provide sufficient care at home, your dog may be treated as an outpatient, but if you cannot care for your dog, it will need supportive nutritional care in the veterinary hospital so that it is adequate nutrients.
If your dog 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 dog water and pureed foods, with the dog’s head slightly elevated so that it can swallow easily. Fluids can also be administered subcutaneously (under the skin).