Sensorineural Hearing Loss Flashcards
Presbycusis:
How does it present?
What are the factors affecting it’s onset and severity?
How is it managed?
N.B. Most common cause of hearing loss
➊ Bilateral, symmetrical loss of high-frequency hearing over many years
➋ Genetics, noise exposure, smoking, HTN, DM, PVD
➌ Hearing aids, Hearing tactics
Noise-induced:
What are the 2 ways in which noise can cause it?
What does TTS stand for?
→ What is it?
→ What can occur if there are repeated episodes of it?
➊ One-time exposure to an intense ‘impulse’ sounds or Continuous exposure to loud sounds over an extended period of time e.g. machinery, gunfire, loud music
➋ Temporary Threshold Shift
→ Brief hearing loss that occurs after noise exposure and completely resolves with rest
→ Permanent threshold shift
Drug-induced:
Which medications are ototoxic?
• Aminoglycosides – Progressive loss of hair cells, affecting high frequency first, as well as vestibular organs (dizziness/imbalance)
• Loop diuretics – Temporary, yet rapidly reversible hearing loss due to oedema in the stria vascularis
• Macrolides – Temporary
• Antimalarials e.g. Quinine, Chloroquine
Acoustic Neuroma (Vestibular Schwannoma):
What is this?
Where does it grow?
How does it present?
→ If large enough, what other symptoms would you expect?
What does the presence of it bilaterally indicate?
How is it diagnosed?
How is it managed?
➊ Benign, slow-growing tumour from overproduction of Schwann cells
➋ Cerebellopontine Angle
➌ Asymmetrical/Unilateral SNHL, Tinnitus, Dizziness
→ CNVII (Facial) symptoms - Forehead won’t be spared as it it’s a LMN palsy
➍ Neurofibromatosis type II
➎ MRI
➏ • 6-monthly MRI scans if < 40mm
• Surgery if > 40mm
Labyrinthitis:
What is it usually associated with?
How does it present?
Which quick test is used to diagnose it?
→ What does a +ve result indicate?
How is it managed?
➊ Viral URTI
➋ Acute Vertigo, associated with HL, Tinnitus, and Ear fullness
➌ Head Impulse Test
→ Peripheral cause of vertigo e.g. labyrinthitis or vestibular neuronitis
➍ • Acute - Prochlorperazine, Antihistamine for N+V symptoms
• Prophylactic – Betahistine
Meniere’s Disease:
What is it due to?
How does it present?
How is it managed?
How does the disease progress?
➊ Endolymphatic hydrops (build-up in inner ear)
➋ Recurrent attacks of Vertigo lasting 12-24 hrs with unilateral hearing loss, tinnitus, and ear fullness
➌ • Acute - Prochlorperazine, Antihistamine for N+V symptoms
• Prophylactic – Betahistine
➍ • Early stages – Vestibular/cochlear symptoms may occur in isolation. Hearing loss (low frequency) and tinnitus recede fully.
• After 1-2 yrs – Complete set of symptoms
• Late stages – Progressive deterioration of hearing
Sudden Sensorineural HL (SSNHL):
What is it defined as?
How does it most commonly present?
How is it managed?
➊ 30dB+ hearing loss > 3 consecutive frequencies within 72 hrs, w/o any obvious cause
➋ Unilateral (95%) – 30-65% spontaneous recovery
→ Bilateral is a lot less common with a lower chance of any recovery, therefore is an emergency
➌ Treat underlying cause, Steroids
