We defined 'an interaural difference in the summating potential/action potential (SP/AP) ratio from the ipsilateral hearing-impaired side to the contralateral normal-hearing side of > or =0.15' as a positive result for a novel 'relative criterion' for the diagnosis of unilateral Ménière's disease. A uniform result could be derived only between a positive ECoG result and the side of disease in 78.7% subjects by conventional absolute criterion (SP/AP > or =0.42). By adding the relative criterion, we found that the diagnostic value increased greatly in specificity (91.2%) and increased slightly in positive predictive rate (79.2%), but decreased greatly in sensitivity (28.8%) and decreased slightly in negative predictive rate (52.5%). In addition, we verified which ear had the disease in all positive cases.
Copyright 2008 S. Karger AG, Basel.