The Tympanogram

Summary

In this educational video, Dr. Ted Venema explains tympanometry, a quick and non-invasive test assessing middle ear function. He describes how a tympanogram reflects air pressure changes in the outer ear canal and how these correlate with the middle ear's status. Normal findings indicate equal pressure on both sides of the tympanic membrane, facilitating sound transmission. Abnormal results, such as Type C and Type B tympanograms, can indicate conditions like early otitis media or fluid-filled ears. Tympanometry is a valuable tool for identifying conductive hearing loss, commonly used by audiologists and pediatricians.

Takeaways

• 😀 Tympanometry is a quick, non-behavioral test that assesses middle ear function.
• 😀 The test measures how much sound bounces back from the tympanic membrane as air pressure changes.
• 😀 A normal tympanogram shows minimal sound bouncing back at room air pressure, indicating efficient sound transmission.
• 😀 The tympanogram shape resembles a tent, peaking at room air pressure when middle ear function is normal.
• 😀 Negative air pressure in the middle ear can indicate early otitis media, reflected in a type C tympanogram.
• 😀 Advanced otitis media results in a type B tympanogram, characterized by a flat line due to fluid in the middle ear.
• 😀 Tympanometry is valuable for diagnosing conductive hearing loss when there's an air-bone gap in audiometry.
• 😀 Different tympanogram types can indicate various conditions, such as otosclerosis and fluid buildup.
• 😀 The test is commonly used by audiologists, pediatricians, and hearing instrument practitioners.
• 😀 Sensory neural hearing loss shows a normal tympanogram since there's no associated middle ear pathology.

Q & A

What is tympanometry?

Tympanometry is a non-invasive test that evaluates the function of the middle ear by measuring how sound bounces back from the tympanic membrane in response to changes in air pressure.

What is the main assumption behind tympanometry?

The main assumption is that the normal middle ear has equal air pressure on both sides of the tympanic membrane, which is crucial for optimal sound transmission.

How does tympanometry differ from pneumatic otoscopy?

Tympanometry measures the amount of sound reflected from the tympanic membrane as air pressure changes, while pneumatic otoscopy assesses the movement of the eardrum in response to air pressure.

What does a normal tympanogram look like?

A normal tympanogram is shaped like a tent, with a peak at room air pressure, indicating that the least amount of sound is bouncing back off the eardrum.

What does a Type C tympanogram indicate?

A Type C tympanogram, which has its peak over negative air pressure, suggests early otitis media, where the middle ear pressure is negative, causing the eardrum to be retracted.

What does a Type B tympanogram indicate?

A Type B tympanogram shows a flat line, indicating that the middle ear is filled with fluid, preventing normal movement of the eardrum and sound transmission.

How is tympanometry performed?

Tympanometry is performed by inserting a probe into the ear canal that creates an airtight seal and then changes the air pressure while measuring sound reflection from the tympanic membrane.

What is the significance of a peak in the tympanogram?

The peak in the tympanogram indicates the optimal point of sound transmission when the air pressure is equal on both sides of the tympanic membrane.

Why is tympanometry important in audiology?

Tympanometry is important because it helps identify conductive hearing loss and middle ear conditions quickly, providing essential information for further diagnosis and treatment.

What type of hearing loss is typically associated with abnormal tympanograms?

Abnormal tympanograms are often associated with conductive hearing loss, where there is a problem in the middle ear affecting sound conduction.