The authors carry out a retrospective study of the diagnostic procedures used in a series of 50 acoustic neuromas. AEP were performed for thirty-four neuromas at some stage of their history. The findings were perfectly normal for eight of them, which represents a sensitivity level of 76%. Various elements likely to account for this are put forward, then the role of AEP and MRI in the diagnostic strategy for neuroma is discussed in the light of this study. Finally, the authors emphasize the necessity to regularly evaluate the diagnostic methods in order to guarantee their quality and reliability.