Hearing By Emily Hodgson and Joshua Bower
What is the stapedius reflex? Stapedius muscle controlled by CN VII The reflex occurs to tighten the tympanic membrane, thus reducing movement and dampening sound to protect the inner ear
What are the THREE types of hearing loss? [3] Central Sensorineural Conductive How is it tested?
Give THREE causes of conductive hearing loss [3] Cerumen (wax) Otitis media and externa Tumour Otosclerosis
Give THREE causes of sensorineural hearing loss [3] Damage to cochlea or CN VIII Old age Medications Immune disorders Noise exposure Trauma Tumours
What is tinnitus? A term to describe any sounds a person can hear from inside their body, rather than from an outside source
What are the TWO types of tinnitus? Pulsatile (sound of blood flow) Drug-induced
Give TWO examples of drugs which can cause tinnitus - Aspirin/NSAIDs (common indicator for salicylate poisoning) - ABx (incl chloramphenicol, gentamicin, vancomycin, bleomycin) - CV drugs (ACEi, ßblocker) - Cancer drugs (incl vincristine) - Diuretics (incl furosemide) - Antimalarials (quinine-based drugs)
The Vestibular System
What is vertigo? Illusion of movement
What are the TWO types of vertigo? Peripheral (inner ear damage) Labyrinthine (drugs, infection) Vestibular nerve (infection, tumour) Central (cerebellum) e.g. demyelination, vertebrobasillar insufficiency, Menieres
What are the THREE things required for balance? Proprioception Vision Vestibular How is it tested?
List THREE causes of a Romberg +ve patient [3] Sensory ataxia Tabes dorsalis Vestibular system damage