Audiograms and Typanometry Flashcards
Briefly describe what is plotted on the X and Y axis of an audiogram and the common notation used for each ear for masking, air and bone conduction.
X axis: frequency in hertz
Y axis: volume in Db
Left ear air conduction is denoted with an X
Right ear air conduction is denoted with an O
Masking is when a noise stimulus is presented to the non test ear.
‘[‘Is used to denote masked bone conduction of Right ear
‘]’ is used to denote masked bone conduction of Left ear
Non masked bone conduction is denoted with a triangle.
What does tympanometry test?
Tympanometry is an examination used to test the condition of the middle ear and mobility of the tympanic membrane and the conduction bones by creating variations of air pressure in the ear canal. Tympanometry is an objective test of middle-ear function.
Briefly describe what is plotted on the X and Y in tympanometry testing?
X axis is pressure Y axis is compliance
What is the likely diagnosis from the audiogram?
Conductive hearing loss
What is the likely diagnosis from the audiogram?
Meniere’s Disease: low frequency sensorineural hearing loss
What is the likely diagnosis from the audiogram?
Mixed hearing loss as at one point bone conduction drops below air conduction but at other points bone conduction is greater than 10dB
What is the likely diagnosis from the audiogram?
Noise induced hearing loss, sensorineural hearing loss with a dip at 4k Hz
What is the likely diagnosis from the audiogram?
Normal hearing
What is the likely diagnosis from the audiogram?
Otosclerosis. Conductive hearing loss with a bone conduction dip at 2K Hz. (Caharts notch)
What is the likely diagnosis from the audiogram?
Presbyacusis: a high frequency sensorineural hearing loss
Describe which type typanogram is shown and the potential cause?
Type C.
Negative pressure in the middle ear could be cause by congestion or eustacian tube dysfunction.
Describe which type typanogram is shown and the potential cause?
Type A.
Normal middle ear function, pressure in the middle ear is the same as that in the external auditory meatus.
The peak must be between -100 to +50 mm/H2O to indicate normal middle ear function.
Describe the type of tympanogram and a possible cause?
Type B.
Middle ear dysfucntion, indicates fluid in the middle ear.
If there is a flat line but at a higher level on the y axis aka greater middle ear volume this indicates there may be a perforation of the tympanic membrane also.
