In conductive hearing loss sound cannot travel properly through the ear canal, eardrum or middle ear bones to reach the inner ear. Common causes are earwax, fluid behind the eardrum, perforation and otosclerosis, and many of them can be fixed.
Key symptoms
- Muffled hearing, often in one ear
- Feeling of a blocked or full ear
- Own voice sounds loud (autophony)
- Ear pain or discharge if there is infection
What you find on exam
- Otoscopy: wax, foreign body, fluid, perforation or a retracted eardrum
- Weber test lateralizes to the affected ear
- Rinne test: bone conduction louder than air conduction on the affected side
- Pneumatic otoscopy: reduced eardrum movement with fluid
Tests
- Audiogram: gap between air and bone conduction thresholds
- Tympanometry: flat curve with fluid or perforation, stiff curve in otosclerosis
- CT of the temporal bones if cholesteatoma, trauma or a malformation is suspected
Treatment basics
- Earwax: softening drops, irrigation or removal with a curette
- Middle ear fluid: watchful waiting, ear tubes if it persists with hearing loss
- Perforation: keep the ear dry, many heal; surgical repair (tympanoplasty) if not
- Otosclerosis: hearing aid or stapes surgery
- Refer to ENT and audiology when the cause is unclear or the loss persists
Red flags
- Sudden hearing loss with Weber going to the good ear (suggests sensorineural loss)
- Persistent one-sided discharge or a white mass behind the eardrum
- Hearing loss with facial weakness, vertigo or severe ear pain
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.