Dizziness of peripheral etiology

Dizziness
Dizziness is a subjective feeling of imbalance. It is accompanied by:
 * an objective disorder of the interplay of position and movement –  deviations and falls ,
 * vegetative symptoms (nausea, vomiting, heart rate changes),
 * possibly anxiety.

Division

 * 1) vestibular
 * 2) * peripheral – damage to the labyrinth or n. VIII,
 * 3) * central – damage to the nuclei, pathways or cerebellum.
 * 4) extravestibular – with eye disorders and proprioception

The most common etiology of vestibular vertigo

 * overloading of the apparatus due to movement or an inappropriate gravitational field (weightlessness),
 * inflammations, tumors, injuries, toxins, drugs...

Symptoms
Peripheral disorder – harmony of individual symptoms (nystagmus, falls, deviations…).

Central disorders – characterized by disharmony - there is no connection between nystagmus and falls hearing impairment is absent, often there are other neurological symptoms.

Characteristics of dizziness

 * nature (turning, swaying, feeling of falling, weakness),
 * prodromes of dizziness (pressure in the ear, headache, tinnitus),
 * provoking factors (smoking, alcohol, drugs, position, movement, noise, optical sensations…),
 * accompanying manifestations (hearing loss, tinnitus, vegetative symptoms, neuro symptoms),
 * duration and intensity – vertigo primarily means spinning dizziness,
 * symptoms – malaise, vomiting, sweating, palpitations, nystagmus and ataxia (gait disorder).

Peripheral vestibular syndrome
It is caused by impairment of the balance system and/or nerve. In general, the more peripheral the lesion, the more accurate the patient's sense of the condition.

Unilateral disability
There is rotational vertigo with nausea, usually hearing is also affected. Difficulty worsens with head movements.

Bilateral disability
The patient complains of gait disturbances and unsteadiness (so-called ataxia). Difficulties worsen in the dark and on an uneven surface, there is often blurred vision during rapid head movements (so-called oscillopsia). Paradoxically, a bilateral chronically progressing lesion does not have many symptoms.

Nystagmus
Spontaneous nystagmus is almost always present – ​​horizontal or horizontal-rotational, unidirectional, often II-III degrees. In this syndrome, vertigo without nystagmus and nystagmus without vertigo do not occur - eye fixation inhibits peripheral nystagmus (to prove it, we must avoid fixation - we use, for example, Frenzel glasses - thick glasses (+15D)...).
 * the intensity of nystagmus increases when looking in the direction of the fast component (Alexander's law ),
 * there is a positive correlation between the intensity of vertigo and nystagmus.

Nystagmus shows signs of fatigue – when the patient tries to stay longer with the eyes in one position, it disappears over time.
 * to the side of the diseased labyrinth it is irritating, to the opposite side it is destructive.

Symptoms
The syndrome is harmonious – all deviations have the same direction (eyes, movements...), only the fast component of the nystagmus goes in the opposite direction.
 * The intensity of the symptoms is determined by the size of the difference between the two apparatuses - tonic deviations are always directed to the side of the weaker apparatus (the stronger one pushes it...), i.e. to the side of the lesion - the slow component of the nystagmus goes to the side of the lesion, the fast component (given by the cerebral cortex's desire for correction) is in the opposite direction.
 * The direction of standing deviation depends on the position of the head, it usually deviates behind the affected ear – if the right ear is affected and we turn our head to the right, we fall backwards.

Benign paroxysmal vertigo
This is one of the most common causes of peripheral vertigo. A typical example is paroxysmal vestibular dysfunction.
 * the basis is the pathology of the posterior semicircular canal caused by the degeneration of the utricular macula - damage occurs after trauma, after surgery in the middle ear, after infection, aging.

Etiology
Small particles of cells containing minerals (otoconia) are released from the macula and travel into the canal - when moving the head, they affect the flow of endolymph, causing irritation.

Clinical picture
typical - with a certain position of the head, severe rotational vertigo occurs:
 * the patient's position is always the same - dizziness usually disappears within a few seconds,
 * other parts of the ear are not damaged (no tinnitus or hearing loss...).

Therapy

 * maneuver according to Semont – the goal is to remove otoconia from the canal.

Vestibular neuronitis

 * a common cause of vertigo - there is a sudden, complete, unilateral loss of vestibular function
 * etiology – probably viruses
 * symptom – sudden onset, severe rotational vertigo, nausea and vomiting, hearing loss and tinnitus are not
 * within a few days the situation will be corrected
 * treatment – corticoids