Reflexes related to the inner ear

Timothy C. Hain, MD Page last modified: June 18, 2009

VOR (vestibulo-ocular Reflex)

• Stabilizes eye in space
• Necessary to see while head is in motion.
  • Rotational movement in 3D includes roll, pitch and yaw.
  • Linear movement along the same axes.(heave -- up/down, surge-- front/back, sway -- side-side)
• Disorders include
  • Bilateral loss
    • Test for bilateral loss with the DIE (Dynamic Illegible 'E' test)
      • Distance vision with head still
      • Distance vision with head moving (horizontal or vertical, 1-2 hz)
      • Normal: 0-2 lines change.
      • Abnormal: 4-7 lines drop with movement
    • Other tests of lesser utility
      • OCR
      • Head-thrust
      • Ophthalmoscope test
      • Head-shaking test
  • Unilateral loss or imbalance
    • Test for unilateral loss at bedside with head-shaking nystagmus or vibration
      • Head-shaking is about 75% sensitive to unilateral loss
      • Vibration is about 95% sensitive to unilateral loss
  • Test for imbalance by assessing spontaneous nystagmus
    • This test works best acutely (i.e. in the first few days)
  • VEMP test for unilateral saccule loss (research test)
  • Cross-coupling
  • Manifests as positional nystagmus
  • Test with positional testing such as Dix-Hallpike test

VSR (Vestibulo-spinal reflex)

• Stabilizes body
• Helps maintain desired orientation to environment
• Test for VSR using Romberg test
  • Eyes Closed Tandem Romberg (6 seconds)
  • Eyes Open Tandem Romberg
  • Eyes Closed Regular Romberg Eyes
  • Open Regular Romberg
• Other tests of uncertain utility
  • Quix test
  • Fukuda tests