Reflexes related to the inner ear
Timothy C. Hain, MD
Page last modified: January 5, 2008
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
© Copyright May 22, 2008 , Timothy C. Hain, M.D. All rights reserved. Last saved on May 22, 2008