Electrocochleography and intranasal allergen challenge as investigational tools in patients with inhalant allergy and Ménière's disease

Objectives: To expand on a prior study investigating the relation between inhalant allergy and Ménière's disease using electrocochleography and to present data from five patients heretofore unmentioned in previous reports. Study Design: Prospective study of five patients identified with Ménière's disease and inhalant allergy in the practices of two faculty otolaryngologists. Methods: Patients were tested twice using electrocochleography: once as a baseline and again 20 minutes following intranasal challenge with the allergen to which they were most sensitive. Results: Three patients had no prior history of immunotherapy, and all were found to have a > 15% increase in summating potential (SP)/action potential (AP) ratio after antigen challenge. However, only one of these patients developed audiovestibular symptoms. Two patients had a history of immunotherapy. One of these patients was tested using three different antigens to which she was highly sensitive on skin testing, one of which provoked audiovestibular symptoms on environmental exposure. Postchallenge electrocochleography, however, demonstrated normal SP/AP ratios with only one antigen causing a > 15% increase. The other patient had elevated SP/AP ratios both before and after challenge and developed no audiovestibular symptoms despite a > 15% increase. Conclusions: Previous work using this investigational tool has identified that all patients with a normal electrocochleography were asymptomatic from an audiovestibular standpoint at the time of postchallenge testing. An elevated SP/AP was not reliably correlated with audiovestibular symptoms in this group of patients. Further investigation in this area will examine the utility of using the variability of the SP and AP to predict audiovestibular symptoms.