Effect of bone-conducted vibration of the midline forehead (Fz) in unilateral vestibular loss (uVL). Evidence for a new indicator of unilateral otolithic function.
Recently, a new indicator of vestibular otolithic function has been reported: it is a series of negative-positive myogenic potentials recorded by surface electrodes on the skin beneath the eyes in response to bone-conducted vibration (BCV) delivered to the forehead at the hairline in the midline (Fz). The potential is called the ocular vestibular-evoked myogenic potential (oVEMP) and the first component of this (n10) is a small (approximately 8 microV), short latency (~ 10 ms), negative potential. In healthy subjects, who are looking up, the n10 responses to Fz bone-conducted vibration are symmetrical beneath the two eyes. In the present investigation, in 17 patients with unilateral surgical vestibular loss, marked asymmetries were observed between the n10 beneath the two eyes: n10 is small or absent beneath the eye on the side opposite the operated ear, confirming previous evidence that n10 is a crossed vestibulo-ocular response unlike p13 of bone-conducted vibration cervical VEMPs (cVEMPs) is a ipsilateral vestibular response and also it is absent in this type of subjects. These results, together with evidence from patients with superior vestibular neuritis allow us to conclude: the asymmetry of the n10 response to Fz bone-conducted vibration is an indicator of utricular macula/superior vestibular nerve dysfunction on the operated side in patients with unilateral vestibular loss.
MSA, ENT Academy Center, Cassino, Italy.
L
L
Manzari
A M
AM
Burgess
I S
IS
Curthoys
D000328:Adult; D000368:Aged; D005260:Female; D005546:Forehead; D006801:Humans; D008297:Male; D008875:Middle Aged; D010037:Otolithic Membrane / Q000503:physiopathology*; D011446:Prospective Studies; D015837:Vestibular Diseases / Q000503:physiopathology*; D014732:Vibration
Neurology. 2005 May 24;64(10):1682-8
15911791
Exp Brain Res. 2006 Nov;175(2):256-67
16761136
Arch Neurol. 1988 Jul;45(7):737-9
3390028
Neurology. 1995 Oct;45(10):1927-9
7477996
Curr Opin Neurol. 2008 Feb;21(1):29-35
18180649
J Neurol Neurosurg Psychiatry. 2003 Jun;74(6):771-8
12754349
Ann N Y Acad Sci. 2005 Apr;1039:54-67
15826961
Audiol Neurootol. 2008;13(6):396-404
18663292
Exp Brain Res. 1995;103(1):174-8
7615033
Acta Otolaryngol. 1969 Oct;68(4):350-62
5309166
Neurology. 2007 Apr 10;68(15):1227-9
17420408
J Neurol Neurosurg Psychiatry. 1994 Feb;57(2):190-7
8126503
Acta Otolaryngol. 1997 Jan;117(1):66-72
9039484
Clin Neurophysiol. 2004 Nov;115(11):2567-73
15465446
Clin Neurophysiol. 2009 Mar;120(3):588-93
19211301
Clin Neurophysiol. 2007 Jul;118(7):1488-93
17475548
Exp Brain Res. 2000 Feb;130(3):277-97
10706428
Clin Neurophysiol. 2005 Aug;116(8):1938-48
15979939
Clin Neurophysiol. 2009 Aug;120(8):1567-76
19632152
J Neurosci. 1994 Oct;14(10):6058-70
7931562
Clin Neurophysiol. 2008 Sep;119(9):2135-47
18639490