[Three cases of Lermoyez's syndrome and its pathophysiology].

Two cases of bilateral Lermoyez's syndrome and one case of unilateral Lermoyez's syndrome are reported. The patients had recurrent episodes of vertigo with improvement of hearing or tinnitus, which is characteristic is Lermoyez's syndrome. In case 1, a 48-year-old female, dehydration with glycerol or furosemide induced nystagmus and improved bilateral hearing and the gain of the vestibulo-ocular reflex, while overhydration with drinking water impaired bilateral hearing with disappearance of nystagmus. These findings indicate that she had endolymphatic hydrops in both ears, suggesting that simultaneous changes in bilateral cochlear and vestibular function induce Lermoyez's syndrome. In case 3, a 52-year-old female, which we already reported, endolymphatic collapse in both ears may have changed bilateral inner ear function, resulting in Lermoyez's syndrome. On the other hand, patients 2, a 47-year-old male, experienced a vertigo attack with improvement of unilateral hearing after defibrinogenation therapy. In this case, slowly developing insufficiency of the inner ear blood supply may have caused the gradual hearing loss. It seemed that decreasing blood viscosity by defibrinogenation allowed blood to rush into the labyrinth, causing vertigo but at the same time improving hearing. We proposed that there are two types of Lermoyez's syndrome, bilateral (cases 1 and 3) and unilateral (case 2).