Transcript QOD

A 43-year old patient goes to an audiologist because he is no longer able to
hear the television or participate in normal conversations. The nurse takes the
patient’s history and discovers that he has worked as a roadie for several major
rock bands over the past 25 years. The audiologist performs the standard
hearing tests and discovers a Weber test with left lateralization and positive
(normal) Rinne Test. Based on these results the audiologist uses an
audiometer and determines that the patient has a hearing threshold of 70
decibels.
What does the result of the Weber test indicate about hearing?
What is a normal Rinne Test and what does it indicate about hearing?
What does a threshold of 70 decibels tell you about the patients hearing?
Why can’t the patient hear the television or normal conversation?
Based on the test results which ear does the patient have hear loss it and is it due to
loss of bone conducation or sensory perception?
Based on these results, does the patient likely have damage to the ear ossicles,
tympanic membrane, oval window, or inner ear structures (cochlea and organ of Corti)?
SPECIFICALLY, how would the involved structures be damaged?
1) Large AMPLITUDE noise (high DB) causes increased displacement of tectorial
membrane
2) Hair cells (stereocilia) are ripped from tectorial membrane
3) Thus ion channels don’t open as effectively
4) Fewer action potentials
5) Less perception of sound!
Low Amplitude
HIGH Amplitude