EN4.14 | Conductive and Sensorineural Hearing Loss — Summary & Reflection

KEY TAKEAWAYS

Hearing loss is classified as conductive (CHL), sensorineural (SNHL), or mixed:

• CHL: air-bone gap on PTA; Rinne negative; Weber to affected (worse) ear; causes: wax, effusion, perforation, otosclerosis, ossicular problems; often reversible.
• SNHL: no air-bone gap; Rinne positive; Weber to better (unaffected) ear; causes: presbyacusis (most common in elderly), NIHL (4 kHz notch), SSNHL (emergency), ototoxicity, acoustic neuroma.
• NIHL: bilateral symmetric 4 kHz notch; caused by noise ≥85 dB TWA; irreversible; prevention via hearing protection is the primary management.
• SSNHL: ≥30 dB SNHL at ≥3 frequencies within 72 hours; same-day referral; PTA + MRI (exclude acoustic neuroma in 6–15%); high-dose systemic steroids; intratympanic steroids as salvage.
• Management of SNHL: hearing aids (first line); cochlear implant for profound bilateral loss; no medical reversal of established NIHL or presbyacusis.
• Tuning-fork trap: Weber lateralises to AFFECTED ear in CHL, AWAY from affected ear in SNHL — do not invert.

REFLECT

Return to the two patients in the opening scenario. Patient A (the retired teacher with gradual bilateral hearing loss) almost certainly has presbyacusis — a normal part of ageing for which hearing aids are the mainstay. Patient B (who woke up deaf) has SSNHL — and every hour without treatment slightly reduces his chance of recovery. Reflect on how a primary care doctor or general physician encountering Patient B might handle this differently from an ENT specialist — and on what system-level barriers (cost of MRI, steroid contraindications in a diabetic patient, lack of same-day ENT access in rural India) could impede optimal care. What would you do if you were the only doctor available and MRI was not accessible within 24 hours?