Challenges of recording human fetal auditory-evoked response using magnetoencephalography.
OBJECTIVE
Our goals were to successfully perform fetal auditory-evoked responses using the magnetoencephalography technique, understand its problems and limitations, and propose instrument design modifications to improve the signal quality and success rate.


METHODS
Fetal auditory-evoked responses were recorded from four fetuses with gestational ages ranging from 33-40+ weeks. The signals were recorded using a gantry-based superconducting quantum interference device. Auditory stimulus was 1 kHz tone burst. The evoked signals were digitized and averaged over an 800 ms window.


RESULTS
After several trials of positioning and repositioning the subjects, we were able to record auditory-evoked responses in three out of the four fetuses. Since the superconducting quantum interference device array design was not shaped to fit over the mother's abdomen, we experienced difficulty in positioning the sensors over the fetal head.


CONCLUSIONS
Based on this pilot study, we propose instrument design that may improve signal quality and success rate of the fetal magnetic auditory-evoked response.
Eswaran
H
H
Department of Applied Science, University of Arkansas at Little Rock, USA.
Lowery
C L
CL
Robinson
S E
SE
Wilson
J D
JD
Cheyne
D
D
McKenzie
D
D
D004867:Equipment Design; D005072:Evoked Potentials, Auditory; D005260:Female; D005333:Fetus / Q000502:physiology*; D006801:Humans; D015225:Magnetoencephalography / Q000295:instrumentation / Q000592:standards*; D010865:Pilot Projects; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000295:instrumentation / Q000592:standards*