Labyrinthitis
Encyclopedia
Labyrinthitis is an inflammation of the inner ear
, and a form of unilateral vestibular dysfunction. It derives its name from the labyrinths that house the vestibular system
(which sense changes in head position). Labyrinthitis can cause balance disorder
s.
In addition to balance control problems, a labyrinthitis patient may encounter hearing loss and tinnitus
. Labyrinthitis is usually caused by a virus
, but it can also arise from bacteria
l infection, head injury
, extreme stress, an allergy
or as a reaction to a particular medication
. Both bacterial and viral labyrinthitis can cause permanent hearing loss, although this is rare.
Labyrinthitis often follows an upper respiratory tract infection
(URI).
. The vestibular system is a set of sensory inputs consisting of three semicircular canals, sensing changes in rotational motion, and the otolith
s, sensing changes in linear motion. The brain combines visual cues with sensory input from the vestibular system to determine adjustments required to retain balance. When working properly, the vestibular system also relays information on head movement to the eye muscle, forming the vestibulo-ocular reflex
, in order to retain continuous visual focus during motion. When the vestibular system is affected by labyrinthitis, rapid, undesired eye motion (nystagmus), often results from the improper indication of rotational motion. Nausea, anxiety, and a general ill feeling are common due to the distorted balance signals that the brain receives from the inner ear.
This can also be brought on by pressure changes such as those experienced while flying
or scuba diving
.
Recovery from a permanently damaged inner ear typically follows three phases:
s, derealization
and depression
. Often a panic attack is one of the first symptoms to occur as labyrinthitis begins. While dizziness can occur from extreme anxiety, labyrinthitis itself can precipitate a panic disorder. Three models have been proposed to explain the relationship between vestibular dysfunction and panic disorder:
Rehabilitation strategies most commonly used are:
These exercises function by challenging the vestibular system. Progression occurs by increasing the amplitude of the head or focal point movements, increasing the speed of movement, and combining movements such as walking and head turning.
One study found that patients who believed their illness was out of their control showed the slowest progression to full recovery, long after the initial vestibular injury had healed. The study revealed that the patient who compensated well was one who, at the psychological level, was not afraid of the symptoms and had some positive control over them. Notably, a reduction in negative beliefs over time was greater in those patients treated with rehabilitation than in those untreated. "Of utmost importance, baseline beliefs were the only significant predictor of change in handicap at 6 months followup."
Prochlorperazine
is commonly prescribed to help alleviate the symptoms of vertigo and nausea.
Because anxiety interferes with the balance compensation process, it is important to treat an anxiety disorder
and/or depression
as soon as possible to allow the brain to compensate for any vestibular damage. Acute anxiety can be treated in the short term with benzodiazepines such as diazepam
(Valium); however, long-term use is not recommended because of the addictive nature of benzodiazepines and the interference they may cause with vestibular compensation and adaptive plasticity. Benzodiazepines and any other form of mind or mood altering addictive drug should not be used on patients with addictive history.
Evidence suggests that selective serotonin-reuptake inhibitors
may be more effective in treating labyrinthitis. They act by relieving anxiety symptoms and may stimulate new neural growth within the inner ear, allowing more rapid vestibular compensation to occur. Trials have shown that SSRIs do in fact affect the vestibular system in a direct manner and can decrease dizziness.
Some evidence suggests that viral labyrinthitis should be treated in its early stages with corticosteroids such as prednisone
, and possibly antiviral medication such as valacyclovir and that this treatment should be undertaken as soon as possible to prevent permanent damage to the inner ear.
Inner ear
The inner ear is the innermost part of the vertebrate ear. In mammals, it consists of the bony labyrinth, a hollow cavity in the temporal bone of the skull with a system of passages comprising two main functional parts:...
, and a form of unilateral vestibular dysfunction. It derives its name from the labyrinths that house the vestibular system
Vestibular system
The vestibular system, which contributes to balance in most mammals and to the sense of spatial orientation, is the sensory system that provides the leading contribution about movement and sense of balance. Together with the cochlea, a part of the auditory system, it constitutes the labyrinth of...
(which sense changes in head position). Labyrinthitis can cause balance disorder
Balance disorder
A balance disorder is a disturbance that causes an individual to feel unsteady, for example when standing or walking. It may be accompanied by feelings of giddiness or wooziness, or having a sensation of movement, spinning, or floating...
s.
In addition to balance control problems, a labyrinthitis patient may encounter hearing loss and tinnitus
Tinnitus
Tinnitus |ringing]]") is the perception of sound within the human ear in the absence of corresponding external sound.Tinnitus is not a disease, but a symptom that can result from a wide range of underlying causes: abnormally loud sounds in the ear canal for even the briefest period , ear...
. Labyrinthitis is usually caused by a virus
Virus
A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...
, but it can also arise from bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
l infection, head injury
Head injury
Head injury refers to trauma of the head. This may or may not include injury to the brain. However, the terms traumatic brain injury and head injury are often used interchangeably in medical literature....
, extreme stress, an allergy
Allergy
An Allergy is a hypersensitivity disorder of the immune system. Allergic reactions occur when a person's immune system reacts to normally harmless substances in the environment. A substance that causes a reaction is called an allergen. These reactions are acquired, predictable, and rapid...
or as a reaction to a particular medication
Medication
A pharmaceutical drug, also referred to as medicine, medication or medicament, can be loosely defined as any chemical substance intended for use in the medical diagnosis, cure, treatment, or prevention of disease.- Classification :...
. Both bacterial and viral labyrinthitis can cause permanent hearing loss, although this is rare.
Labyrinthitis often follows an upper respiratory tract infection
Upper respiratory tract infection
Upper respiratory tract infections are the illnesses caused by an acute infection which involves the upper respiratory tract: nose, sinuses, pharynx or larynx...
(URI).
Symptoms
A prominent and debilitating symptom of labyrinthitis is severe vertigoVertigo (medical)
Vertigo is a type of dizziness, where there is a feeling of motion when one is stationary. The symptoms are due to a dysfunction of the vestibular system in the inner ear...
. The vestibular system is a set of sensory inputs consisting of three semicircular canals, sensing changes in rotational motion, and the otolith
Otolith
An otolith, , also called statoconium or otoconium is a structure in the saccule or utricle of the inner ear, specifically in the vestibular labyrinth of vertebrates. The saccule and utricle, in turn, together make the otolith organs. They are sensitive to gravity and linear acceleration...
s, sensing changes in linear motion. The brain combines visual cues with sensory input from the vestibular system to determine adjustments required to retain balance. When working properly, the vestibular system also relays information on head movement to the eye muscle, forming the vestibulo-ocular reflex
Vestibulo-ocular reflex
The vestibulo-ocular reflex is a reflex eye movement that stabilizes images on the retina during head movement by producing an eye movement in the direction opposite to head movement, thus preserving the image on the center of the visual field. For example, when the head moves to the right, the...
, in order to retain continuous visual focus during motion. When the vestibular system is affected by labyrinthitis, rapid, undesired eye motion (nystagmus), often results from the improper indication of rotational motion. Nausea, anxiety, and a general ill feeling are common due to the distorted balance signals that the brain receives from the inner ear.
This can also be brought on by pressure changes such as those experienced while flying
Aviation
Aviation is the design, development, production, operation, and use of aircraft, especially heavier-than-air aircraft. Aviation is derived from avis, the Latin word for bird.-History:...
or scuba diving
Scuba diving
Scuba diving is a form of underwater diving in which a diver uses a scuba set to breathe underwater....
.
Recovery
Recovery from acute labyrinthine inflammation generally takes from one to six weeks; however, it is not uncommon for residual symptoms (dysequilibrium and/or dizziness) to last for many months or even years if permanent damage occurs.Recovery from a permanently damaged inner ear typically follows three phases:
- An acute period, which may include severe vertigo and vomiting
- approximately two weeks of sub-acute symptoms and rapid recovery
- finally a period of chronic compensation which may last for months or years.
Labyrinthitis and anxiety
Chronic anxiety is a common side effect of labyrinthitis which can produce tremors, heart palpitations, panic attackPanic attack
Panic attacks are periods of intense fear or apprehension that are of sudden onset and of relatively brief duration. Panic attacks usually begin abruptly, reach a peak within 10 minutes, and subside over the next several hours...
s, derealization
Derealization
Derealization is an alteration in the perception or experience of the external world so that it seems unreal. Other symptoms include feeling as though one's environment is lacking in spontaneity, emotional coloring and depth. It is a dissociative symptom of many conditions, such as psychiatric and...
and depression
Clinical depression
Major depressive disorder is a mental disorder characterized by an all-encompassing low mood accompanied by low self-esteem, and by loss of interest or pleasure in normally enjoyable activities...
. Often a panic attack is one of the first symptoms to occur as labyrinthitis begins. While dizziness can occur from extreme anxiety, labyrinthitis itself can precipitate a panic disorder. Three models have been proposed to explain the relationship between vestibular dysfunction and panic disorder:
- Psychosomatic model: vestibular dysfunction which occurs as a result of anxiety.
- Somatopsychic model: panicPanicPanic is a sudden sensation of fear which is so strong as to dominate or prevent reason and logical thinking, replacing it with overwhelming feelings of anxiety and frantic agitation consistent with an animalistic fight-or-flight reaction...
disorder triggered by misinterpreted internal stimuli (e.g., stimuli from vestibular dysfunction), that are interpreted as signifying imminent physical danger. Heightened sensitivity to vestibular sensations leads to increased anxiety and, through conditioning, drives the development of panic disorder.
- Network alarm theory: panic which involves noradrenergic, serotonergicSerotoninSerotonin or 5-hydroxytryptamine is a monoamine neurotransmitter. Biochemically derived from tryptophan, serotonin is primarily found in the gastrointestinal tract, platelets, and in the central nervous system of animals including humans...
, and other connected neuronal systems. According to this theory, panic can be triggered by stimuli that set off a false alarm via afferents to the locus ceruleusLocus ceruleusThe locus coeruleus , is a nucleus in the brainstem involved with physiological responses to stress and panic. It was discovered in the 18th century by Félix Vicq-d'Azyr....
, which then triggers the neuronal network. This network is thought to mediate anxiety and includes limbic, midbrain and prefrontal areas. Vestibular dysfunction in the setting of increased locus ceruleus sensitivity may be a potential trigger.
Treatment
Vestibular rehabilitation therapy (VRT) is a highly effective way to substantially reduce or eliminate residual dizziness from labyrinthitis. VRT works by causing the brain to use already existing neural mechanisms for adaptation, plasticity, and compensation.Rehabilitation strategies most commonly used are:
- Gaze stability exercises - moving the head from side to side while fixated on a stationary object (aimed to restore the Vestibulo-ocular reflexVestibulo-ocular reflexThe vestibulo-ocular reflex is a reflex eye movement that stabilizes images on the retina during head movement by producing an eye movement in the direction opposite to head movement, thus preserving the image on the center of the visual field. For example, when the head moves to the right, the...
) An advanced progression of this exercise would be walking in a straight line while looking side to side by turning the head.
- Habituation exercises - movements designed to provoke symptoms and subsequently reduce the negative vestibular response upon repetition. Examples of these include Brandt-Daroff exercises.
- Functional retraining - including postural control, relaxation, and balance training.
These exercises function by challenging the vestibular system. Progression occurs by increasing the amplitude of the head or focal point movements, increasing the speed of movement, and combining movements such as walking and head turning.
One study found that patients who believed their illness was out of their control showed the slowest progression to full recovery, long after the initial vestibular injury had healed. The study revealed that the patient who compensated well was one who, at the psychological level, was not afraid of the symptoms and had some positive control over them. Notably, a reduction in negative beliefs over time was greater in those patients treated with rehabilitation than in those untreated. "Of utmost importance, baseline beliefs were the only significant predictor of change in handicap at 6 months followup."
Prochlorperazine
Prochlorperazine
Prochlorperazine is a dopamine receptor antagonist that belongs to the phenothiazine class of antipsychotic agents that are used for the antiemetic treatment of nausea and vertigo. It is also a highly-potent typical antipsychotic, 10-20x more potent than chlorpromazine...
is commonly prescribed to help alleviate the symptoms of vertigo and nausea.
Because anxiety interferes with the balance compensation process, it is important to treat an anxiety disorder
Anxiety disorder
Anxiety disorder is a blanket term covering several different forms of abnormal and pathological fear and anxiety. Conditions now considered anxiety disorders only came under the aegis of psychiatry at the end of the 19th century. Gelder, Mayou & Geddes explains that anxiety disorders are...
and/or depression
Clinical depression
Major depressive disorder is a mental disorder characterized by an all-encompassing low mood accompanied by low self-esteem, and by loss of interest or pleasure in normally enjoyable activities...
as soon as possible to allow the brain to compensate for any vestibular damage. Acute anxiety can be treated in the short term with benzodiazepines such as diazepam
Diazepam
Diazepam , first marketed as Valium by Hoffmann-La Roche is a benzodiazepine drug. Diazepam is also marketed in Australia as Antenex. It is commonly used for treating anxiety, insomnia, seizures including status epilepticus, muscle spasms , restless legs syndrome, alcohol withdrawal,...
(Valium); however, long-term use is not recommended because of the addictive nature of benzodiazepines and the interference they may cause with vestibular compensation and adaptive plasticity. Benzodiazepines and any other form of mind or mood altering addictive drug should not be used on patients with addictive history.
Evidence suggests that selective serotonin-reuptake inhibitors
Selective serotonin reuptake inhibitor
Selective serotonin re-uptake inhibitors or serotonin-specific reuptake inhibitor are a class of compounds typically used as antidepressants in the treatment of depression, anxiety disorders, and some personality disorders. The efficacy of SSRIs is disputed...
may be more effective in treating labyrinthitis. They act by relieving anxiety symptoms and may stimulate new neural growth within the inner ear, allowing more rapid vestibular compensation to occur. Trials have shown that SSRIs do in fact affect the vestibular system in a direct manner and can decrease dizziness.
Some evidence suggests that viral labyrinthitis should be treated in its early stages with corticosteroids such as prednisone
Prednisone
Prednisone is a synthetic corticosteroid drug that is particularly effective as an immunosuppressant drug. It is used to treat certain inflammatory diseases and some types of cancer, but has significant adverse effects...
, and possibly antiviral medication such as valacyclovir and that this treatment should be undertaken as soon as possible to prevent permanent damage to the inner ear.
External links
- DizzyTimes.com
- Dr. Rauch's Online Otology Clinic — video clips
- Labyrinthitis.org.uk
- Vestibular neuritis and labyrinthitis - "Labyrinthitis and related conditions" - "Vestibular rehabilitation therapy"
- Inner ear healthboard
- Labyrinthitis and vestibular neuritis