What does an air-bone gap indicate?

The difference between the results of air conduction and bone conduction tests is known as the air-bone gap. An air-bone gap may mean a problem in the outer or middle ear. If there is no gap between air and bone conduction this may indicate a problem in the inner ear (cochlea).

What is the air-bone gap for sensorineural hearing loss?

Sensorineural hearing loss (SNHL) is characterized by elevated air-conduction thresholds, with an air-bone gap of 10 dB or less. This type of hearing loss is the result of damage to the cochlea, retrocochlear pathway, or both. Clarity and intensity of sound are both degraded.

What are 3 causes of conductive hearing loss?

Causes of Conductive Hearing Loss

• Fluid in your middle ear from colds or allergies.
• Ear infection, or otitis media.
• Poor Eustachian tube function.
• A hole in your eardrum.
• Benign tumors.
• Earwax , or cerumen, stuck in your ear canal.
• Infection in the ear canal, called external otitis.
• An object stuck in your outer ear.

How do you differentiate conductive and sensorineural hearing loss?

Sensorineural hearing loss, which means there is a problem occurring in either the inner ear or the auditory nerve, which delivers sound to the brain. Conductive hearing loss, which means sound is not reaching the inner ear, usually due to an obstruction or trauma.

Why is the air-bone gap important?

Perhaps the most important diagnostic feature of the audiogram is the air-bone gap. By distinguishing between conductive and sensorineural impairments, the air-bone gap profoundly influences the patient’s care. A false air-bone gap can lead to inappropriate medical or surgical treatment.

How do you determine conductive hearing loss?

Weber’s test is performed by softly striking a 512-Hz tuning fork and placing it midline on the patient’s scalp, or on the forehead, nasal bones, or teeth. If the hearing loss is conductive, the sound will be heard best in the affected ear.

What is the most common cause of conductive hearing loss?

According to Rothholtz, the most common cause of conductive hearing loss is a buildup of earwax that muffles sound. Rothholtz adds that some other types of conductive hearing loss include: Otosclerosis: This causes bone from the cochlea to grow onto the stapes bone in the middle ear, making it more difficult to hear.

Why is air conduction better in sensorineural hearing loss?

The inner ear is more sensitive to sound via air conduction than bone conduction (in other words, air conduction is better than bone conduction). Therefore, the affected ear is more sensitive to bone-conducted sound. Occlusion effect: Most of the sound transmitted via bone conduction travels through to the cochlea.

What is better air conduction or bone conduction?

Normal finding: Air conduction is better than bone conduction. The patient should be able to hear the sound of the tuning fork adjacent to their ear, persist for approximately twice as long as the sound they heard over their mastoid process. This is considered a “positive test.”

Why is air conduction better hearing?

The inner ear is more sensitive to sound via air conduction than bone conduction (in other words, air conduction is better than bone conduction). Therefore, the affected ear is more sensitive to bone-conducted sound.