Info
🌱 來自: Huppert’s Notes
Hearing loss🚧 施工中
Hearing loss
• Physical exam: Otoscopic exam, Weber test (performed by pressing the handle of the tuning fork to the center of the forehead), Rinne test (performed by comparing the sound heard when a tuning fork is placed on the mastoid bone behind the ear to when a tuning fork is held near the ear, in order to compare bone and air conduction)
• Differential diagnosis:
- Conductive hearing loss
• Symptoms: Decreased perception of sound (especially low frequency), but often can still hear loud noises well
• Etiologies: Lesion in the external/middle ear
- External canal: Cerumen impaction, otitis externa, exostoses (bony outgrowths often due to cold water)
- Tympanic membrane: Perforation secondary to trauma/infection, clot in meatus, tear
- Middle ear: Effusion (otitis media, allergic rhinitis), otosclerosis (bony immobilization of stapes), neoplasm
• Physical exam: CARWA – Conductive hearing loss will have Abnormal Rinne (bone conduction is better than air) and Weber with sound lateralizing to Affected side (louder in bad ear)
• Diagnosis: Clinical diagnosis (no specific labs/imaging required)
• Treatment: Treat underlying cause, hearing aids, soften and irrigate cerumen, tympanoplasty if needed, stapedectomy for otosclerosis
- Sensorineural hearing loss
• Symptoms: Hearing loss; may have more difficulty with high frequency sounds
• Etiologies: Lesion in the cochlea or CN VIII (auditory branch)
- Presbycusis (most common): Gradual, symmetric hearing loss (especially at high frequencies) associated with aging, due to degeneration of the sensory cells at the base of the cochlea; most marked at high frequencies with slow progression to lower frequencies
- Noise-induced: Chronic loud noise damages hair cells in the organ of Corti
- Inflammatory/infectious: Infection (e.g., viral cochleitis), congenital infections, autoimmune hearing loss
- CNS: Acoustic neuromas (especially if marked hearing difference between ears), meningitis, multiple sclerosis, syphilis
- Drug-induced: Aminoglycoside antibiotics, furosemide, ethacrynic acid, cisplatin, quinidine, aspirin (tinnitus)
• Physical exam: Normal Rinne test (air conduction better than bone); Weber test with sound lateralizing to the unaffected side (louder = good ear)
• Diagnosis: Clinical diagnosis (no specific labs/imaging required)
• Treatment: Treat underlying cause, hearing aids, cochlear implants