Neurology- core conditions 2 Flashcards
Vestibular dysfunction
A disturbance in the balance system due to peripheral or central causes. When its peripheral the problem is located within the inner ear. When its central the problem is located within the brain
Symptoms of vestibular dysfunction
• Vertigo
• Nausea
• Vomiting
• Intolerance to head movement
• Unsteady gait
• Nystagmus
• Patient cant drive and must inform the DVLA
Central causes of vestibular dysfunction
Any problems involving the brainstem or cerebellum such as:
• Posterior circulation infarct
• Tumour
• MS
• Vestibular migraine
• These cause a sustained, non-positional vertigo
Peripheral causes of vestibular dysfunction
• Benign paroxysmal positioning vertigo
• Menieres disease
• Vestibular neuritis
Examinations to distinguish between peripheral and central vertigo
• Examination- DANISH cerebellar exam, Romberg’s test
• HINTS exam- Head impulse test, Nystagmus, test of skew
Benign Paroxysmal positional vertigo
• Brief episodes (<1 minute typically) of mild to intense dizziness - usually triggered by specific changes in postural and head position
• Can also cause nystagmus, loss of balance, nausea
• No auditory symptoms
• Patients are asymptomatic between attacks
Differences between peripheral and central vertigo
Peripheral vertigo- Sudden onset, short duration, Hearing loss and tinitus, intact coordination, severe nausea
Central vertigo- gradual onset, Persistent duration, No hearing loss or tinnitus, Impaired coordination, Mild nausea
Causes of BPPV
• Displaced otoliths i.e. calcium carbonate crystals in the ear, they now flow freely in the SCCs and can stimulate CNVIII to cause vertigo and nystagmus
• Can become displaced by viral infection / trauma / ageing / idiopathic
Diagnosis of BPPV
DIX-Hallpike manoeuvre
- Patient sits up with their head to 45 degrees
- The patient is then quickly laid down with their head still at 45 degrees
- This can bring on the vertigo
- The eyes also need to be observed for rotatory geotropic nystagmus towards the affected ear (for up to a minute) for a positive response to occur
- Repeat the test with the head turned in the other direction to check the other ear
Treatment of BPPV
Epley maneuver
- Patient sits up on a bed with their head 45 degrees left
- They lie down keeping their head in this position and wait 30 seconds
- They then turn their head 90 degrees right so its 45 degrees again but right this time
- They then roll on to their right side and sit up shortly after
- When they sit up the head should be central with the neck flexed 25 degrees towards the chest
- ^ Thats for if the problem is on the left ear, if its the right ear repeat but on the opposing side
- The idea is to move the crystals in to a position that does not affect endolymph flow
Meds not needed unless the patient has extreme nausea
Menieres disease
A chronic, incurable disorder of the vestibular system that causes sudden attacks of vertigo, tinnitus and sensorineural hearing loss. It usually starts in one ear but spreads to both over time.
Menieres disease triad
- Vertigo
- Tinnitus
- Fluctuating sensorineural hearing loss (associated with vertigo attacks before becoming more permanent, starts by affecting low frequencies)
Other symptoms you may get for Menieres disease
- Nausea and vomiting
- Unsteadiness and unexplained drop attacks
- Feeling of pressure in the ear
- Can also maybe see unidirectional nystagmus during acute attacks
- These vertigo attacks occur suddenly and most commonly last 2-3 hours but can last just minutes or more hours
- It often takes 2 days or so for the symptoms to fully disappear
- And the attacks can happen in clusters over a week or they may be separated by months/years
- Tends to occur in patients aged 40-50
Causes of Menieres disease- unknown but factors which contribute are:
- Improper fluid drainage e.g. blockage or anatomic abnormality of the endolymphatic spaces causing a build up of endolymph and therefore a higher pressure (endolymph hydrops)
- Viral infections
- Genetic predisposition
- Stress
Diagnosis of Menieres disease
- Two episodes of vertigo, each lasting 20 minutes or longer but not longer than 12 hours
- Hearing loss as verified by a hearing test
- Tinnitus or a feeling of fullness in the ear
- Exclusion of any other cause
Treatment for menieres disease- prophylaxis
- Anti-vertigo medication i.e. betahistine (helps reduce frequency of attacks)
- Salt restriction to help reduce fluid retention in the ear
- Avoid caffeine/alcohol/ tobaccco
- There is no cure
Acute attack of menieres management
- Anti-emetics i.e. prochlorperazine
- Anti-histamine i.e. promethazine to help reduce nausea, vomiting and vertigo
Surgery menieres disease
- Endolymphatic sac procedure to decompress the sac
- Labyrinthectomy
Vestibular neuritis
Inflammation of the vestibulocochlear nerve caused by a virus - therefore distorting the signals require to sense movement and balance
Symptoms of vestibular neuritis
- Severe vertigo lasting weeks to months
- Dizziness
- Nausea and vomiting
- Balance issues
- May have had a recent viral illness
Vestibular neuritis vs Labrynthitis
It is very similar to labrynthitis but labrynthitis affects the whole of the vestibulocochlear nerve whereas vestibular neuritis just affects the vestibular branch. Therefore, labrynthitis also presents with additional symptoms of sensorineural hearing loss and/or tinnitus.
Diagnosis of vestibular neuritis
The head impulse test
- The patient sits upright, with their gaze on the examiners nose
- The examiner holds the patients head and rapidly jerks it 10-20 degrees in one direction whilst the patient continues looking at the nose
- The head is slowly moved back to the centre before repeating in the opposite direction
- Normal vestibular system = eyes will keep fixed on the examiners nose
- Abnormal vesitibular system = eyes will saccade i.e. rapidly move back and forth
- This helps diagnose a peripheral cause of vertigo - will be normal if the cause is central
Vestibular neuritis-nerve affected
The vestibular nerve transmits signals from the vestibular system i.e. the semicircular canals and the vestibule to the brain, this helps with balance. The cochlea transmits signals which help with hearing. Together they form the vestibulococlear nerve (CNVIII)
