ENT - Audiometry Flashcards
What is audiometry?
Testing a patient’s hearing by playing a variety of tones and volumes using headphones and a bone conduction device
Helps differentiate and identify conductive and sensorineural hearing loss
What is an audiogram?
A chart that documents the volume at which patients can hear different tones
Helps visualise hearing thresholds across frequencies
On an audiogram, what is plotted on the x and y axis?
X axis
Frequency in hertz (Hz) from low to high pitched
Y axis
Volume in dB, loud at bottom to quiet at top, indicates how sensitive patient’s hearing is
What does it indicate if a patient’s hearing is plotted lower on the audiogram?
The louder the sound required for the patient to hear, the worse their hearing is
Helps assess severity of hearing loss
Plotted at quietest volume patient can hear each frequency
What are the different symbols used for air and boen conduction?
X – Left-sided air conduction
] – Left-sided bone conduction
O – Right-sided air conduction
[ – Right-sided bone conduction
What does it mean when a patient has normal hearing on an audiogram?
All readings will be between 0 and 20 dB, at the top of the chart
In patients with sensorineural hearing loss, where will both air and bone conduction readings be plotted?
More than 20 dB, below the 20 dB line on the chart
Sensorineural hearing loss can affect one side, one side more than the other, or both sides equally
What distinguishes conductive hearing loss on an audiogram?
Bone conduction readings will be normal (0-20 dB) while air conduction readings are greater than 20 dB
In mixed hearing loss, what is the relationship between air and bone conduction readings?
Both will be more than 20 dB, with a difference of more than 15 dB (bone conduction > air conduction)
Mixed hearing loss indicates a combination of conductive and sensorineural components
