Infection of the vestibular nerve is called Vestibular Neuritis or Vestibular Neuronitis. The infection affects the vestibular nerve function and causes a disturbance in maintaining balance.
A viral infection may trigger an inflammation of the vestibular nerve. It may start with a cold, flu or a sore throat.
Symptoms of a vestibular neuritis are:
- Dizziness or Vertigo.
- Nausea/VomitingDifficulty in focusing – especially during head movement.
Labyrinthitis and Vestibular Neuritis are similar in many aspects., In Vestibular neuritis, only the vestibular portion of the vestibulocochlear nerve gets inflamed. The inflammation affects the balance function.
However in Labyrinthitis, both the parts of vestibulocochlear nerve get affected causing balance as well as hearing problems.
Vertigo and dizziness symptoms are more intense in the 1st couple of days The severity of the symptoms may then decrease. The patients usually recover from the effects of vertigo in the subsequent three weeks. Some patients experience imbalance and dizziness symptoms for several months especially on rapid head movement.
The videonystagmoscopy (VNG) examination identifies a spontaneous nystagmus, which is horizontal. This nystagmus gets reduced on optic fixation. Video Head impulse test shows a deficit in the vestibulocular reflex on the affected side.
VEMP will help decide whether the inferior or superior vestibular nerve is affected.The Subjective visual vertical(SVV) test shows a misinterpretation of the vertical plane, shifted to the damaged side by more than 10°. Craniocorpography (CCG) will reveal a rotation to the affected side on Unterberger test.
The patient of vestibular neuritis may have reduced Dynamic Visual Acuity (DVA).
Audiogram and Impedance Measurements are conducted to make sure there is no cochlear or middle ear impairment.
The neurological examination is normal. Over a period of a few days, the vestibular symptoms subside and the patient may observe lessened sensations of spinning or rotation. The neurovegetative symptoms like nausea & vomiting improve too. However, the feeling of imbalance may remain for some time.
If the vertigo is coupled with unusual headaches and neurological symptoms like slurring of speech, muscle weakness or loss of altered consciousness a brain MRI must be done to rule out any central pathology
Treatment consists of two parts; one, managing the symptoms of vestibular neuritis and second, starting vestibular rehabilitation treatment at the earliest.
The first step of the treatment plan is to control the symptoms of vestibular neuritis.
Doctors recommend oral drugs to check nausea and vomiting. In cases of acute nausea and vomiting, the patient may be put on IV fluids to control the dehydration.
Vestibular suppressant medicines help control vertigo and dizziness sensations. Vestibular suppressants should not be taken for more than three days. Long-term use of these medicines is strictly not recommended as they maycause recovery to be delayed and at times incomplete leading the patient to have residual symptoms.
Steroids may be used in the 1st five days of the onset of infection to reduce swelling and inflammation of the vestibular nerve.
Vestibular rehabilititation should be started at the earliest once the acute symptoms subside.The purpose of VR is to retrain the brain to adapt to the changes in balance function. This is called vestibular compensation.
Your doctor will evaluate the balance system specifically targeted at the following functions.
- Vestibulospinal system – evaluated to check maintenance of balance during standing and walking.
- Vestibulo ocular system – ability to stabilize vision at rest and during head movement.
- Posture and Center of gravity control.
Depending on the outcome of the evaluation, suitable vestibular rehabilitation exercises are recommended to the patient.
The balance exercises retrain the brain to adjust to the new circumstances and maintain steadiness despite confusing signals given by the dysfunctional balance system. The difficulty levels are advised as per the patient’s condition, disability and progress. These exercises can be done under guidance of a therapist or at home. These patient- customized balance exercises must be done 2 – 3 times a day for effective results. Vestibular rehabilitation specialists provide specific instructions on how to perform the exercises, identify which exercises can be done at home, and provide other home safety tips to prevent falls. In patients who do not respond well to home-based exercise programs, rehabilitation under the guidance of a therapist is required.