Ear's the Thing
This cranial nerve carries both hearing and balance information
What is CN VIII (vestibulocochlear nerve)?
When Weber testing lateralizes to the affected ear, this type of hearing loss is most likely present.
What is conductive hearing loss?
A 72-year-old patient reports difficulty understanding conversations, especially in noisy environments. Audiometry demonstrates bilateral, symmetric loss of hearing sensitivity that is greatest at high frequencies. Otoscopy is normal, and Weber lateralizes to the ear with better hearing. This condition is most likely.
What is presbycusis?
This antibiotic class is classically associated with irreversible cochlear and vestibular toxicity.
What are aminoglycosides?
While the utricle and saccule detect linear acceleration, these structures detect angular acceleration
What are the semicircular canals?
Weber lateralizes to the left, Rinne is positive bilaterally, and the patient reports right-sided hearing loss. This is the most likely diagnosis.
What is right-sided sensorineural hearing loss?
A 50-year-old factory worker presents with difficulty hearing high-pitched sounds. Audiometry demonstrates bilateral sensorineural hearing loss with a sharp decrease in thresholds at approximately 4 kHz followed by partial recovery at higher frequencies. Tympanic membranes are normal. This condition is most likely.
What is noise-induced sensorineural hearing loss?
A patient receiving chemotherapy develops bilateral tinnitus and difficulty hearing high-frequency sounds. Audiometry reveals bilateral high-frequency sensorineural hearing loss. The tympanic membranes appear normal. This medication-associated condition is most likely.
What is cisplatin-induced ototoxicity?
A lesion within the internal auditory meatus causes inability to close the ipsilateral eye, loss of forehead movement, and decreased taste sensation from the anterior two-thirds of the tongue. Although this canal also contains the nerve responsible for hearing and balance, the primary nerve injured in this patient is this
What is the facial nerve (CN VII)?
A patient states they "can't hear out of the left ear." Weber lateralizes to the left, and Rinne demonstrates bone conduction greater than air conduction on the left but air conduction greater than bone conduction on the right. The hearing deficit is best classified as this.
What is left-sided conductive hearing loss?
A patient reports decreased hearing in the right ear. Audiometry demonstrates:
The tympanic membrane appears retracted on examination. This condition is most likely.
What is right-sided conductive hearing loss due to middle ear dysfunction (such as otitis media with effusion)?
A physician counsels a patient that new-onset tinnitus, hearing loss, or disequilibrium should prompt immediate evaluation because several commonly prescribed medications can damage the cochlea or vestibular system. Four classic examples are these.
What are cisplatin, furosemide, vancomycin, and high-dose aspirin?