Optimization of distortion product otoacoustic emission (DPOAE) measurements with the system IL096

Measurements of distortion product otoacoustic emissions (DPOAEs) at Aalborg University are performed with the commercial system ILO96 from Otodynamics. The default measuring setup is not adequate for monitoring the recovery of DPOAEs after noise exposure because (1) data collection is interrupted repeatedly due to the operating mode of the system and (2) it is desired to have control over the presentation order of the primaries f1 and f2, which in the default setup are always presented in an ascending sweep. An optimized setup has been programmed with the ILO96. The setup is able to continuously measure up to 16 user-defined pairs of primaries in a loop mode. Furthermore, a systematic error was found in a particular setup of the system consisting of a mismatch between the primaries programmed to be measured and the ones actually measured. The error was reported to Otodynamics, who verified that the error occurs for this particular model. The ILO96 is no longer under production but it is still widely used for both clinical and research purposes. Therefore, this presentation will explain the new optimized setup as well as the error in the system.