Nystagmus series – Part II
(Peripheral vestibular nystagmus)
“measuring eye movements with precision”
(magnetic field search coil technique)
2) Pathophysiology
“lesion in the vestibular labyrinth or nerve”
*after some time, vestibular adaptation leads to beating toward the lesion
3) Slow-phase waveform
- linear slow-phase drifts
- constant velocity
- sawtooth appearance
4) Associated symptoms
- vertigo
- tendency to fall
- past-point
“symptoms will be toward the side of the lesion”
6) Fixation in peripheral vestibular nystagmus
“suppress the vertical and horizontal components more than torsional”
- pursuit system preventing the vestibular system from moving eyes
2) Pathophysiology
3) Slow-phase waveform
4) Associated symptoms
5) Nystagmus trajectory
“trajectory is according geometrical relationship of semicircular canals”
- mixed horizontal-torsional (most common)
It occurs due to a ‘sum of canal directions of one ear’
6) Fixation in peripheral vestibular nystagmus
7) Making peripheral vestibular nystagmus more noticeable
Alexander’s law
- turn eyes to the direction of the quick phase
Bedside maneuvers
- change head position
- vigorous head-shaking
- hyperventilation
- mastoid vibration
- valsalva maneuvers
9) Peripheral vestibular nystagmus - features
10) Peripheral vestibular nystagmus
11) Peripheral vestibular nystagmus
12) Peripheral vestibular nystagmus
13) Peripheral vestibular nystagmus
14) Peripheral vestibular nystagmus
15) Peripheral vestibular nystagmus
16) Peripheral vestibular nystagmus
17) Peripheral vestibular nystagmus
18) Peripheral vestibular nystagmus
19) Peripheral vestibular nystagmus