All surfaces of the Otoport may be cleaned with an alcohol based wipe or
cloth with antiseptic fluid. Dry the device immediately with tissue.
Do not allow liquid to enter the instrument.
If additional hygienic protection is required, clear plastic infection control
sleeves designed to contain the Otoport during use are available from
Otodynamics.
Otodynamics does not guarantee the accuracy of the test results or the
tests themselves, if accessories other than those supplied by Otodynamics
are used.
1.4
Types of otoacoustic emissions
Otoacoustic emissions are sounds which can be recorded in the ear canal
and which are created by the action of sensory cells within the cochlea.
The sensory cells responsible are the outer hair cells.
Outer hair cells are nearly always damaged or inactive when there is
cochlear hearing loss. Damaged outer hair cells do not produce emissions
so cochlear hearing loss is associated with reduced or absent otoacoustic
emissions.
Damage can occur to one part of the cochlea while other parts remain
normal. This corresponds to hearing loss at some frequencies and
not others. Similarly, otoacoustic emissions can be present at some
frequencies, where hearing is intact, and absent at others, where there is a
hearing loss.
The presence of otoacoustic emissions does not prove that the higher level
auditory system is working normally. They only confirm that the cochlear
environment and sensory outer hair cells are working normally at the
frequencies tested.
The absence of otoacoustic emissions does not always indicate cochlear
pathology. Otoacoustic emissions can be blocked by a malfunctioning
middle ear, or obscured by excessive noise. Absent emissions with normal
middle ear function and a properly conducted test very strongly indicate
that hearing loss is present.
Introduction
CHAPTER ONE
Introduction
12
Summary of Contents for Otoport Advance
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