Examination of the balance system

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In addition to the vestibule, proprioception (cerebellum) and vision are also involved in balance - that's why balance disorders are difficult to assess.

Spontaneous and provoked vestibular phenomena[edit | edit source]

They are objective.

Nystagmus[edit | edit source]

Nystagmus are rhythmic movements of the bulbs in a certain plane and direction with a fast and slow component:

  • the slow component is the response to vestibular stimulation,
  • the fast component is compensation from the CNS,
  • direction of nystagmus – given according to the fast component – ​​rightward, leftward, up, down,
  • planes of nystagmus – horizontal, vertical, rotatory and diagonal.
  • Intensity of nystagmus – 3 degrees:
    • Grade I – nystagmus occurs when looking to one side, to which it then points,
    • II. degree - it can also be observed when viewed directly,
    • III. degree - it can also be observed when looking at the opposite side to the direction of the nystagmus.
  • we further evaluate – frequency, amplitude and angular velocity,
  • positional nystagmus – can be provoked by slowly moving the head into a certain position,
  • positioning nystagmus – provoked by rapid change of position, onset with latency,
  • vertical, diagonal, rotary or multidirectional is always central.

Standing according to Romberg[edit | edit source]

  • lie down, eyes closed.
  • head first straight, then with a turn to both sides.
  • the affected person leans or falls in the direction of the slow component of the nystagmus (behind the diseased ear).
  • we can scan optically and evaluate with posturography.

Deviations of the arms according to Hautant[edit | edit source]

  • forearm, close eyes, watch for half a minute,
  • in a peripheral disorder, both hands deviate in the direction of the slow component of the nystagmus.

Experimental examination of the vestibular system[edit | edit source]

  • in experiments we imitate the irritation or attenuation of the apparatus,
  • we mainly monitor nystagmus, but we can also monitor Romberg and Hautant.

Caloric examination[edit | edit source]

  • the patient is lying down, the head is tilted forward by 30° (verticalize the lateral semicircular canal),
  • through the glasses we watch the eyes,
  • we use water at 30 °C and 44 °C (ie ± 7 °C from body temperature),
  • first we examine both ears gradually (first one, then the other) with cold and then both with warm water,
  • on the stopwatch, we measure the latency to the onset of nystagmus,
  • cold water into the ear canal dampens (heat strengthens) the response of the lateral semicircular canal,
  • we induce 2 nystagmus – one in the contralateral direction (extinction) and the other in the homolateral direction (irritation),
  • nystagmus occurs in this way even in a healthy person.
Evaluation of results
  • bilateral hyporeflexia – the duration of nystagmus is below the physical value.
  • bilateral hyperreflexia – the duration of nystagmus is above the physical value.
  • lateral difference in excitability – difference in times, pathological reduction in excitability of one side.
  • directional dominance – the difference in the size of the deviation, the sum of the values ​​in one direction is noticeably higher than in the other.
  • vestibular areflexia – does not cause nystagmus.

Investigation of rotations[edit | edit source]

  • we stimulate both labyrinths at the same time, on a swivel chair, head tilted forward 30°, eyes closed,
  • we rotate 1 revolution in 6 s, stop suddenly and read the nystagmus,
  • physiologically, nystagmus lasts 25–60s, against the direction of rotation.

Examination of the fistula symptom[edit | edit source]

  • in the presence of a labyrinthine fistula (it is most often in the semicircular canal),
  • blow the balloon into the ear, increase the pressure and if there is a whistle, nystagmus will occur.

Links[edit | edit source]

Related Articles[edit | edit source]

Source[edit | edit source]