Prevalence and characteristics of preoperative balance disorders in cochlear implant candidates

Objectives: The aim of this study was to elucidate the frequency and characteristics of preoperative vertigo symptoms in patients who undergo cochlear implantation (CI), in order to differentiate them from CI-related symptoms. Methods: In a prospective observational study, 47 adult CI candidates were asked about vertigo problems on a question-naire. A subdivision into 3 groups was done: group A (probable otogenic vertigo), group B (possible otogenic vertigo), and group C (not otogenic vertigo). Horizontal semicircular canal function was measured. Patients with vertigo com-plaints were compared to patients without vertigo with regard to the presence of abnormal vestibular function findings. Results: Twenty-five patients (53%) reported preoperative vertigo problems. In 21 (84%), the patient’s history suggested a probable (group A) or possible (group B) otogenic origin. Patients with vertigo more often had abnormal findings on vestibular function testing than did patients without vertigo. This difference, however, was not statistically significant. Conclusions: A considerable number of CI candidates have preoperative vertigo symptoms. These cannot be explained by horizontal semicircular canal function alone. In order to understand why CI patients develop postoperative vertigo, analysis of prospective preoperative vestibular function test findings and vertigo symptoms is necessary