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OAEs and no ABRs

Michael Gorga GORGA at BoysTown.ORG
Fri Mar 15 12:06:19 EST 1996


Everyone is no confronted by infants and young children who present with robust
OAEs and no ABRs.  First the easy part.  I would be interested in knowing if
any of these children had elevated bilirubin levels, perhaps to the point of
requiring transfusions.  We have a small number of ICN graduates with exactly
the same pattern you report who had extreme elevations in their bilirubin
levels.  Bilirubin will cause damage to nerves but not necessarily hair cells, 
whose response are reflected in OAEs.  

That's the easy part.  The hard part is what to do.  Certainly pediatric
neurological assessment could be of value, but I don't think that's what you're
asking.  At the very least, these kids should be followed audiometrically to
determine what sorts of behavioral manifestations there are accompanying this
pattern of response.  Ordinarily, one would not consider amplification on these
children.  Amplification is meant to ameliorate a peripheral hearing loss, but 
the OAEs suggest that no such peripheral hearing loss exists.  Amplifying such 
an ear potentially poses a risk to surviving OHCs.  However, what if as the
child gets a little older their behavior is much like a deaf or hearing
impaired child.  In the face of compeeling evidence that the child behaves as
if he/she is heairng impaired, the risk of damage to OHCs is perhaps less
worrisome (afterall, the child isn't acting like they hear anyway - whats the
risk?).  If you do obtain compelling evidence that the child behaves as if
hearing impaired at some future date, you might consider amplification.  Output
should be reasonably limited and it might be a good idea to monitor the child
very closely, using OAEs.  Still, one should not expect overwhelming evidence
of benefit because you maybe providing assistance to the part of the system
that is not broken.  

Having done the intellectual equivalent of throwing dirt into muddy waters, goo
d luck.  I suspect that there are a fair number of kids like this, and the
number will only continue to rise so long as babies are discharged from
hospital in the first 24 hours of life.  Perhaps we do not have good options to
offer these families today but maybe we will gain better understanding of these
kids and be able to make reasoned recommendations in the future.

Name:		Michael P. Gorga
Address:	BTNRH
		555 North 30th Street
		Omaha, NE   68131
Telephone:	402/498-6604
FAX:		402/498-6638
e-mail:		gorga at boystown.org

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