Reading an Audiogram

1
Reading an Audiogram
2
Air vs. Bone Conduction

• A/C
• Via TDH-50P headphones
• Placed on Pinna
• Checks the validity of entire ear system
• Tests that ipsilateral ear

• B/C
• Bone vibrator
• Placed on Mastoid Process
• Tests the validity of only the inner ear
• Tests better cochlea

3
Things to know about an Audiogram

• Lo to Hi Frequency (abscissa)
• 125 Hertz to 8000 Hertz
• Octave and half-octaves
• Lo to Hi dB (ordinate)
• -10 dB HL to 120 dB HL
• Each dB is equal to one octave
• It is a Legal document

20
4
The Legend
5
Ranges of Hearing Loss

• -10 25 dB HL Normal range
• 26 40 dB HL Mild hearing loss
• 41 55 dB HL Moderate
• 56 70 dB HL Moderately Severe
• 71 90 dB HL Severe
• Greater than 90 dB HL Profound

6
Normal Hearing
7
Conductive Hearing Loss
8
Sensorineural Hearing Loss
9
Mixed Hearing Loss
10
Other Hearing Tests

• Tympanometry
• Acoustic Reflexes
• Speech Audiometry
• Speech Reception Threshold (SRT)
• Speech Discrimination (SD)
• ABR
• ECOCHG (Electrocochleography)
• OAE

11
What about Hearing Aids

• Minimal hearing loss
• Probably no/little benefit
• Moderate hearing loss and usually sensorineural
  hearing loss are good candidates
• Profound hearing loss?
• Could for environmental safety reasons
• Cochlear Implant