The following is a more accessible plain text extract of the PDF sample above, taken from our ENT Notes. Due to the challenges of extracting text from PDFs, it will have odd formatting:
Balance Disorders
Vertigo = illusion of movement
Normal balance requires
Accurate sensory information from
Eyes (vision)
Proprioceptive receptors
Vestibular labyrinth
Co-ordination of information in brain
Normal motor output from CNS to intact musculoskeletal system
A fault in any of the above impairs balance
Vertigo is always a symptom of vestibular defects
Severe if accompanied by nausea and vomiting
Can be caused by
Peripheral vestibular disorders (BPPV, Menieres’, labrynthitis)
Spread of infection from middle ear disease to labyrinth
Central vestibular disorders e.g MS, tumours, infarcts
External insults by drugs, anaemia, hypoglycaemia etc
Benign Paroxysmal Positional Vertigo (BPPV)
Commonest cause of vertigo
Pathophysiology
Detachment of otoconia (calcium carbonate crystals) from the otolith organ of the utricle – fall into posterior semicircular canal (loose inside canal)
Cause symptoms on movement of the head
Aetiology
Head injury
Viral infection
Degenerative changes with aging
Idiopathic
Clinical features
Episodic attacks or vertigo provoked by head movements e.g rolling over in bed/looking upwards
Violent symptoms but last only seconds
No auditory symptoms
Episodes usually last for several months before disappearing but often recur
Both labyrinths may be affected
Management
Reassurance, advice to avoid provoking head position until recovery
Avoid alcohol
Epley maneuvers may help reposition otoconia away from the posterior canal
Medication
Betahistine
Vestibular sedatives e.g prochlorperazine
Antidepressants
Last resort = posterior semicircular canal denervation/obliteration
Meniere’s Disease
A disorder of endolymph control
Pathophysiology
Expansion of endolymph spaces (endolymphatic hydrops) = increased fluid
Increased pressure causes rupture of inner ear membranes
Endolymph + perilymph mix
Causes biochemical disturbance leading to acute vestibule-cochlear failure
Aetiology
Idiopathic
Clinical features
Usually unilateral
Occurs in those aged 30-60yrs
Triad of symptoms
Vertigo
Hearing loss
Tinnitus
Attacks occur in clusters with periods of remission
Each attack lasts several hours
Can be accompanied by N+V
May have warning symptoms before and attack e.g sensation of pressure in the ear, change in character of tinnitus, pain in the neck or increased deafness
Accompanying deafness = sensorineural
Fluctuates in severity
Improves on remission
Associated with speech distortion
Discomfort with loud noises (hyperacusis)
Over time gradually deteriorates
Tinnitus = roaring, low pitched, worse when hearing is most impaired
Management
Acute
Cyclizine
Medical
Vasodilators e.g betahistine
Nicotinic acid
Diuretic + salt restricted diet (electrolyte imbalance theory)
Surgical
If symptoms not controlled by medication
Decompress endolymphatic sac
Selective division of vestibular branch of vestibularcochlear nerve
Labyrinthectomy = guarantees relief from vertigo but at the expense of total hearing loss in that ear
Labyrinthitis/Sudden vestibular failure
Pathogenesis
One peripheral labyrinth suddenly stops working
Can be due to viral infection, head injuries, blockage of end artery supplying the labyrinth, MS, diabetic neuropathy
Clinical features
Rapid onset
Sudden vertigo which persists continuously for days-weeks before improving
May be exacerbated by head movements
N+V
No auditory symptoms
Unless cochlear is involved
Nystagmus
Patients gradually regain balance
Recovery slower and less complete in elderly
Acoustic Neuroma (vestibular schwanomas)
Develop on superior vestibular nerve
Are tumours from schwann cells
Arise from defect on the long arm of cr 22
Rarely become malignant (although with continued growth can compress brainstem = death)
Can be part of an unpleasant syndrome “neurofibromatosis type 2”
Autosomal dominant,...
Buy the full version of these notes or essay plans and more in our ENT Notes.
Ask questions 🙋 Get answers 📔 It's simple 👁️👄👁️
Our AI is educated by the highest scoring students across all subjects and schools. Join hundreds of your peers today.
Get Started