Labyrinthitis and Vestibular Neuritis

Vestibular neuritis and labyrinthitis are disorders resulting from an infection that inflames the inner ear or the nerves connecting the inner ear to the brain. This inflammation disrupts the transmission of sensory information from the ear to the brain. Vertigo, dizziness, and difficulties with balance, vision, or hearing may result. Infections of the inner ear are usually viral; less commonly, the cause is bacterial.

Inner ear structure and function

The inner ear consists of a system of fluid-filled tubes and sacs called the labyrinth. The labyrinth serves two functions: hearing and balance. The hearing function involves the cochlea, a snail-shaped tube filled with fluid and sensitive nerve endings that transmit sound signals to the brain. The balance function involves the vestibular organs. Fluid and hair cells in the three loop-shaped semicircular canals and the sac-shaped utricle and saccule provide the brain with information about head movement.

Signals travel from the labyrinth to the brain via the vestibulo-cochlear nerve (the eighth cranial nerve), which has two branches. One branch (the cochlear nerve) transmits messages from the hearing organ, while the other (the vestibular nerve) transmits messages from the balance organs. The brain integrates balance signals sent through the vestibular nerve from the right ear and the left ear. When one side is infected, it sends faulty signals. The brain thus receives mismatched information, resulting in dizziness or vertigo.

Neuritis (inflammation of the nerve) affects the branch associated with balance, resulting in dizziness or vertigo but no change in hearing. The term neuronitis (damage to the sensory neurons of the vestibular ganglion) is also used.

Labyrinthitis (inflammation of the labyrinth) occurs when an infection affects both branches of the vestibulo-cochlear nerve, resulting in hearing changes as well as dizziness or vertigo.

(Gallardo, 2014)

Symptoms and onset of viral neuritis or labyrinthitis

Symptoms of viral neuritis can be mild or severe, ranging from subtle dizziness to a violent spinning sensation (vertigo). They can also include nausea, vomiting, unsteadiness and imbalance, difficulty with vision, and impaired concentration.

Sometimes the symptoms can be so severe that they affect the ability to stand up or walk. Viral labyrinthitis may produce the same symptoms, along with tinnitus (ringing or noises in the ear) and/or hearing loss.

Treatment during the acute phase

When other illnesses have been ruled out and the symptoms have been attributed to vestibular neuritis or labyrinthitis, medications are often prescribed to control nausea and to suppress dizziness during the acute phase. If symptoms of dizziness or imbalance are chronic and persist for several months, vestibular rehabilitation exercises may be beneficial in retraining the brain’s ability to adjust to the vestibular imbalance. Usually, the brain can adapt to the altered signals resulting from labyrinthitis or neuritis in a process known as compensation. Vestibular rehabilitation exercises facilitate this compensation. The exercises may provide relief immediately, but a noticeable difference may not occur for several weeks. Many people find they must continue the exercises for years in order to maintain optimum inner ear function, while others can stop doing the exercises altogether without experiencing any further problems. A key component of successful adaptation is a dedicated effort to keep moving, despite the symptoms of dizziness and imbalance. Sitting or lying with the head still, while more comfortable, can prolong or even prevent the process of adaptation (Shupert, 2014).