Two-dimensional filter to facilitate detection of transient-evoked otoacoustic emissions

This paper implements a filtering technique to enhance the signal-to-noise ratio (SNR) and, in turn, the detection of transient-evoked otoacoustic emissions (TEOAE´s), generated by healthy human cochlea. One can increase the SNR by compiling an image of recorded TEOAE from more than one stimulus intensity, averaged over a few sweeps, which can be further processed by means of two-dimensional spatial mean filters. Averaging some 60 sweeps recorded to stimuli at several intensity levels requires one-forth of the collection time needed for a classical set of responses (average of 260 sweeps), and obtains approximately the same final SNR. The relation between the performances of the proposed technique and the SNR of the rapidly acquired responses before filtering is also investigated.