Poststapedectomy dizziness. A histopathologic report

Long-term disabling dizziness is a rare but serious postoperative complication of stapedectomy. The temporal bone collection of the Ear Research Institute in Los Angeles includes 117 bones from patients who underwent unilateral or bilateral stapes operations. Of them, nine patients (8 percent) complained of severe long-term postoperative dizziness. Histologic examination of the temporal bones revealed a pathologic condition in the peripheral vestibular system of seven patients; the remaining two patients showed normal maculae, cristae, and vestibular nerve. Pathologic conditions found were suppurative labyrinthitis in one case, endolymphatic hydrops in two cases, fibrous adhesions in the utricle in two cases, and a bone fragment in contact with the saccule in one case. An undiagnosed inferior vestibular nerve schwannoma was present in one case of unilateral stapedectomy that was followed by constant unsteadiness. Because there are many causes of poststapedectomy dizziness, a complete neurotologic evaluation is indicated in every case for a specific diagnosis.