Persistent alternobaric vertigo at ground level.

We recently encountered a 15-year-old female with bilateral tympanostomy tubes who manifested persistent severe vertigo, at ground level, secondary to a unilateral middle-ear pressure of +200 mm H(2)O elicited by an obstructed tympanostomy tube in the presence of chronic nasal obstruction. We believe this is a previously unreported scenario in which closed-nose swallowing insufflated air into her middle ears, resulting in sustained positive middle-ear pressure in the ear with the obstructed tube. Swallowing, when the nose is obstructed, can result in abnormal negative or positive pressures in the middle ear, which has been termed the Toynbee phenomenon. In patients who have vertigo, the possibility that nasal obstruction and the Toynbee phenomenon are involved should be considered.