The Ear: Hearing Loss

Summary table for Differential Diagnosis of Sensorineural Hearing Loss


Condition
Causative agents
Features
Typical audiogram pattern
Mrs J's Pointers!

Age-related hearing loss (presbycusis)

Probably caused by the loss of elasticity of the ossicular chain (the malleus, incus and stapes) through arthritic type changes (otosclerosis)

Debris or cerumen impaction in the external auditory meatus can cause a problem. This commonly exacerbates Presbycusis in older people but can be treated by having ears syringed.

Gradual onset Bilateral high-frequency loss, "downsloping" This you need to know - loss of high frequency perception (steeper sides to the audiogram pattern curve output) - for both ears (bilateral - on both sides!)
Congenital hearing loss Genetic factors, prenatal infections/toxic exposures, birth trauma Present at birth Variable Not on syllabus!
Noise-induced hearing loss Noise exposure Gradual onset, tinnitus common Bilateral high-frequency loss, "notch" at 3,000 to 4,000 Hz

Loud music makes you 'age' as far as your hearing goes!

The 'notch' at 3/4KHz relates to damage to the ear. It would show up as more dB needed to perceive at that pitch!

Sudden hearing loss Viral infections, trauma, vascular, drugs Sudden onset, otologic emergency Variable; may be unilateral or bilateral Not on syllabus!
Neoplastic Acoustic neuroma (vestibular schwannoma), other tumors Usually gradual onset; tinnitus may be present Unilateral loss Not on syllabus!
Meniere's disease Unknown (may be endolymphatichydrops) Fluctuating, progressive hearing loss, tinnitus, vertigo Low-frequency loss, "upsloping" or flat Not on syllabus!
Ototoxicity Chemotherapeutic agents (cisplatin [Platinol], nitrogen mustard), aminoglycosides, furosemide (Lasix), salicylates, quinine May be accompanied by tinnitus, vertigo, nystagmus Usually bilateral, symmetric, high frequency (may be very high frequency) Not on syllabus!
Other Infections: herpes, meningitis, mumps, syphilis, tuberculosis
Systemic disease: vasculitis, renal failure, head injury
Genetic factors: idiopathic
Often gradual onset, associated disease Variable Not on syllabus!