A possible case of saccular endolymphatic hydrops.

The vestibular-evoked myogenic potential (VEMP) is expected to be one of the examinations for saccular function. We report a case of dysequilibrium possibly due to a saccular disorder. A 27-year-old female came to our clinic complaining of severe recurrent dysequilibrium spells for few hours on September 21, 1998. The first attack was only vertigo with bilateral tinnitus for 8 days before. She did not show possible vestibular findings on a routine vestibular test. An electrochochleogram showed the dominant negative summating potential (SP) on both sides, and the furosemide test showed negative findings on both sides. A VEMP test indicated a low amplitude in the right ear, which improved to the normal response after furosemide injection. The amplitude was increased by furosemide administration even in the left ear. These findings suggested bilateral endolymphatic hydrops in the cochlea and saccule especially on the right side. The VEMP test may reveal saccular hydrops, which differs from the conventional Ménière type vertigo.