[Pseudoemissions and false positive findings in measurement of transiently evoked otoacoustic emissions (TEOAE)].
BACKGROUND
Recording procedure of transiently evoked otoacoustic emissions is an important part of diagnostics in pediatric audiology. As a rule of thumb measurable TEOAE excludes more than slight hearing impairment. Nevertheless any interpretation of these measurements in a clinical setting must consider supposed false positive findings (so called pseudoemissions) and real false positive findings in cases of profound hearing loss with reproducible TEOAE and missing auditory evoked potentials.


METHODS
TEOAE recordings in 512 patients were evaluated for recording procedure failure. Possible types of recording procedure failure were divided into failures conditioned by the patients and stimulus or probe dependent failures. In case of insufficient test procedure and absent TEOAE recording procedure was improved and repeated.


RESULTS
In 2 patients with severe to profound hearing loss we discovered reproducible TEOAE whereas auditory evoked potentials were missing. As a stimulus and probe dependent recording procedure failure we saw reproducible pseudoemissions in 3 other patients with profound hearing loss.


CONCLUSIONS
These results indicate that conclusions concerning hearing ability on the base of TEOAE should keep in mind possible pseudoemissions as a result of recording procedure failure. Reported cases with absent auditory evoked potentials and reproducible TEOAE showed that TEOAE recordings in these cases indicate substantially preserved outer hair-cell function independent of profound hearing loss.
Frese
K A
KA
Klinik für Hals, Nasen, Ohrenheilkunde, Kopf- und Halschirurgie Universitätsklinikum der Christian-Albrechts-Universität zu Kiel, Germany. knut.frese@audio.uni-kiel.de
Reker
U
U
Maune
S
S
D016477:Artifacts; D001300:Audiometry, Evoked Response; D001301:Audiometry, Pure-Tone; D001933:Brain Stem / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D003056:Cochlear Nerve / Q000503:physiopathology; D003638:Deafness / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D005072:Evoked Potentials, Auditory / Q000502:physiology; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*; D010897:Pitch Discrimination / Q000502:physiology; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted