We occasionally encounter subjects complaining of dizziness or vertigo that is induced by noise. The exact phenomenon of sound-induced vertigo was little described in medical literature until the celebrated observations of Prof. Pietro Tullio, an Italian biologist in 1929.
Tulio's phenomenon as it was subsequently called has since been described in 5 otological conditions - Superior canal dehiscence, perilymph fistula, Meniere's syndrome, post fenestration surgery, and vestibulofibrosis.
The interesting aspect is that the original Tullio's experiment observed by drilling tiny holes in the semicircular canals of pigeon was meant to demonstrate sound-induced vestibulopathy.
Now, the real interesting aspect is that we do not have a single explanation as to the exact mechanism of this phenomenon. Rather what we have are explanations of possible mechanisms each peculiar to specific disease entity.
Tullio's phenomenon is also now known to be either physiological or pathological. The physiologic Tullio's can be elicited when very loud pure tone sound is presented monaurally, or clicks at 110 decibel to a blindfolded subject on posturographic platform.
The pathologic Tullio's on the other hand are elicited by less loud sound (<70dB nHL) for clicks, or by loud pure tones presented binaurally.
Pathological modifiers suspected in Tullio's phenomenon include pathological contiguity of the tympano-ossicular chain and membranous labyrinth, dislocated ossicular chain, stapes hyperlaxity, fracture of the footplate or of the labyrinth, fibrotic damping of the ossicular chain, fibrosis of the inner ear, traumatic labyrinth, perilym- phatic fistula and endolymphatic hydrops.
References:
1. B-ENT, 2008, 4, Suppl. 8, 27-28
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