Makindo Medical Notes

🎧 Sensorineural Hearing Loss (SNHL) arises from pathology in the inner ear or the vestibulocochlear nerve. ⚡ Sudden idiopathic SNHL is an ENT emergency → treat promptly with steroids ± ENT referral. 💡 Around two-thirds of idiopathic cases improve spontaneously.

📖 About

• Affects millions worldwide; ~9 million people in the UK are deaf or hard of hearing.
• ~6 million are over 60 → presbyacusis (age-related loss) is the most common cause.
• SNHL can be unilateral or bilateral, sudden or progressive, and often accompanied by tinnitus.

🧬 Aetiology

• Idiopathic – sudden SNHL, ~2/3 improve spontaneously.
• Meniere’s disease – triad of episodic vertigo + tinnitus + fluctuating SNHL.
• Presbyacusis – progressive age-related loss of high frequencies.
• Trauma – temporal bone fracture, barotrauma, or haemorrhage.
• Perilymphatic fistula – after barotrauma/loud noise, causes vertigo + SNHL.
• Cogan’s syndrome – autoimmune, steroid responsive.
• Viral – mumps, measles, CMV.
• Stroke – AICA occlusion → 8th nerve ischaemia.
• Ototoxic drugs – aminoglycosides, loop diuretics, platinum chemo.
• Neurological – Multiple Sclerosis.
• Acoustic neuroma – benign vestibular schwannoma → progressive unilateral SNHL ± tinnitus.

🔎 Investigations

• Pure Tone Audiometry (PTA) – gold standard: shows high-frequency loss in presbyacusis.
• MRI of CP angle – if unilateral/progressive loss or suspicion of acoustic neuroma.
• Tympanometry – to rule out middle ear pathology.
• Bloods if systemic cause suspected (autoimmune, viral).

💊 Management

• Steroids – oral or intratympanic glucocorticoids for sudden idiopathic SNHL.
• Antivirals – occasionally used if viral cause suspected (limited evidence).
• Hyperbaric oxygen – may help acute cases (not routine in UK practice).
• ENT referral – urgent if sudden (<72 hrs), unilateral, or progressive loss.
• Rehabilitation:
  • Hearing aids → first-line for persistent or age-related SNHL.
  • Cochlear implants → for severe/profound loss unresponsive to aids.

⚠️ Red Flags (Immediate Referral)

• Sudden unilateral SNHL.
• SNHL + facial nerve palsy, vertigo, or headache → ?stroke or acoustic neuroma.
• Progressive asymmetrical hearing loss.

📊 Prognosis & Follow-Up

• Early treatment (<2 weeks) in sudden SNHL improves recovery odds.
• Regular follow-up audiometry essential in chronic cases (esp. Meniere’s, autoimmune).
• Patients benefit from multidisciplinary support (ENT, audiology, hearing therapy).

📚 References

• NICE CKS: Sensorineural Hearing Loss