Labyrinths and Vestibular: Meniere's, BPPV, acoustic neuroma, viral labyrinthitis, vestibular neuritis Flashcards
Anatomy of vestibular apparatus
In inner ear, petrous part of temporal for protection
Bony labyrinth
-3 semicircular canals
-vestibule
-cochlea
Membranous labyrinth in bony
-semicircular duct opens up into utricle and saccule
-surrounded by perilymph (low Na, high K)
-endolymphatic duct allows fluid circulation
-voltage difference across membranous labyrinth aids with vestibular function
Ménière’s disease vs BPPV
-epidemiology, etiology
-pathophysiology
-symptoms, signs
Meniere’s - excess endolymph
-middle age, M+F
-episodes last mins-hours
-symptoms generally unilateral but may become bilateral with time
-recurrent attacks of vertigo, tinnitus, sensorineural hearing loss, ear pressure
-nystagmus, +ve Romberg test
BPPV - otoliths move into semicircular ducts, cause vertigo when displaced
-most common cause of vertigo
-55s
-episodes last seconds
-nausea, +ve Dix Hallpike manoueuvre
Meniere’s Disease vs BPPV
-diagnosis
-management (practical, attacks, prevention)
-prognosis
ENT assessment confirms diagnosis for both
Meniere’s
-inform DVLA, stop driving until symptoms controlled
Acute - prochlorperazine (typical antipsychotic with antiemetic properties)
Prevention - betahistine (anti-vertigo) and vestibular rehab
Self-limiting- 5-10years but with hearing loss and psychological distress
BPPV
-Epley, vestibular rehab
-Betahistine given but not always effective
Self-limiting but can recur
Acoustic neuroma
-epidemiology, etiology
-pathophysiology
-symptoms, signs
No obvious cause but linked to neurofibromatosis T2
Benign tumour that may compress CN5, 7, 8
Triad of vertigo, hearing loss, tinnitus (CN8), no corneal reflex (CN5), facial palsy (CN7)
Acoustic neuroma
-diagnosis
-management
If suspected => URGENT REFERRAL TO ENT
Gold standard - MRI of CPA
-audiometry
Management
-observe/surgery/radiotherapy
Viral labyrinthitis vs vestibular neuritis
-epidemiology, etiology
-pathophysiology
-symptoms and signs
Viral labyrinthitis - inflammed membranous labyrinth
-40-70, recent URTI
-vertigo exacerbated by mv but not a trigger => N+V
-sensorineural hearing loss, tinnitus
-nystagmus
Vestibular neuritis - inflammation of vestibular nerve
-recent URTI
-vertigo attack lasts hours-days => N+V
-no hearing loss
-nystagmus
Viral labyrinthitis vs vestibular neuritis
-diagnosis
-management (practical, attacks, prevention)
-prognosis
Clinical diagnosis
Self limiting
-prochlorperazine or betahistine can help
Sudden onset sensorineural hearing loss
-key investigations
-causes
-management
Rinne and Weber => sensorineural
URGENT REFERRAL TO ENT in 24HRS for MRI
MAJORITY IDIOPATHIC
-want to exclude acoustic neuroma
High dose CS used for all cases
-PO pred