Vestibular neuritis

Balance control is regulated by the information we obtain from the outside through three channels: vision, proprioceptive receptors, located at the osteoarticular and cutaneous level, which provide information about the position of the body and its movements, and the inner ear. All this information is collected and integrated at the level of the cerebral cortex, cerebellum and brainstem, and nervous orders are given that allow balance to be maintained.

At the level of the inner ear, information is transmitted through the auditory or vestibulocochlear nerve, also called the eighth cranial nerve (VIII CP). This nerve consists of two branches, the cochlear branch, which transmits information about hearing, and the vestibular branch, which is responsible for transmitting the positional information provided by the inner ear to the trunk. If, for whatever reason, there is a inflammation from this branch of the VIII CP there is what is called vestibular neuritis.

How is it produced?

Vestibular neuritis is usually viral in origin. The virus infection, probably in the context of a discharge, a catarrhal picture, causes the nerve becomes inflamed and therefore the transmission of the information about the position collected by the inner ear is altered, not being congruent with the rest of the information provided by the proprioceptive receptors of the body and vision and, consequently, the feeling of balance se perceived as altered, giving a false sense of movement or lack of balance.

In patients over 60 years of age, it should be taken into account that vestibular neuritis is due to possible acute ischemia, due to involvement of the anterior vestibular artery, a branch of the internal auditory artery, dependent in turn on the anteroinferior cerebellar artery. This artery is responsible for the irrigation of various structures of the inner ear, such as the utricle, the vestibular canals and part of the saccule. A deficit in the irrigation from this artery can lead to a nerve injury that leads to vestibular neuritis.

Symptoms

Vestibular neuritis presents a very typical picture of abrupt onset and is characterized by the presence of head instability, dizziness, spinning sensation, and lack of balance. It can be accompanied by intense vegetative symptoms, such as nausea, vomiting, sweating, or palpitations. It is a very unpleasant sensation, so it can trigger an anxiety attack.

Since it is an isolated involvement of the vestibular branch of the vestibulocochlear nerve, hearing is not altered and tinnitus is not appreciated, unlike what would occur in the case of labyrinthitis or labyrinthitis.

The patient with vestibular neuritis may feel unstable for two to three weeks. When walking, there will be a lateralization of the gait towards the healthy side, since it will pull the patient to walk straight according to his perception of balance.

The Romberg test consists of the exploration of balance on the basis that two of the three systems of control of balance are needed for it to be preserved. The patient is made to stand with eyes closed and the patient is observed to fall to one side. In the case of vestibular neuritis, it will fall to the injured side, which is called Romberg positive.

These patients also often present with abnormal eye movement, known as nystagmus. Nystagmus is an involuntary movement of the eyes in which the eyes quickly lateralize to the side and then slowly return to the normal position. In patients with vestibular neuritis, a horizontal nystagmus of the eyes will occur towards the healthy side.

Diagnosis

Vestibular neuritis is essentially diagnosed by the patient's description of symptoms and physical examination. It is important to perform an otological examination, as well as a complete neurological examination, assessing gait disturbances and the presence or absence of the Romberg sign.

In some cases, if there are doubts about a possible hearing impairment, a

If the symptoms of instability persist after two or three weeks, it may be advisable to carry out an electrical conduction study using an electroneurogram (ENG).