CAP 12 Dizziness/Vertigo

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This curriculum note is mostly concerned with giving you a structure for dealing with these patients.  HITs and VOR are unlikely to be tested in the exam.

Key:  Establish what the patient actually means.

Vertigo is the illusion of motion of the patient or the surroundings.  “Spinning” is rare.  Patients normally describe the feeling of being at sea.  Vertigo is always made worse by movement.

Associated symptoms are related to the failure of the persons’ internal gyroscope: difficulty walking, standing, nausea, vomiting, pallor, sweating.  Tinnitus or hearing loss implies labyrinth or CN 8 involvement.

Vertigo does not cause LOC.  Light headedness is often also described as dizziness, but is more of an orthostatic, vagal type response, there is no illusion of movement.

If the patient truly has vertigo then the next step is to work out if it is serious or not serious:

Serious :  Cerebellar or brainstem infarct or haemorrhage, MS, acoustic neuroma

Not serious: Menieres, Vestibular neuronitis/labrynthitis, BPV, motion sickness, trauma, zoster, aminoglycosides, migraine, alcohol.

(I may be being slightly flippant here, the above ‘not serious’ conditions can still render a normal person bed bound for weeks at a time).

Use history and examination to work out if vertigo is caused centrally by brain, or peripherally by sensory organs.

Most people hate seeing patients with vertigo because of the perceived ‘woolyness’ of the difference between peripheral and central causes.  Leaving many to opt for ‘could be central’  referral dustbin.  However if you examine properly using HIT, and Skew-deviation you can be more accurate than an MRI.

KEY Examination finding – nystagmus.

Patients given something for their vertigo may not show nystagmus.  Therefore you need to assess these patients BEFORE you give them drugs.  Pure vertical nystagmus is weird and always abnormal.

Horizontal nystagmus is usually peripheral but not always. Torsional nystagmus can be either.

Central Peripheral
Migraine BPV
Veretbrobasilar ischaemia Menieres
Cereberllar infarction Vesitbular Neuritis
MS
Acoustic Neuroma

 

BPV

Brief <30s vertigo induced by changes in head position.  Things are OKAY when still.  Caused by dislodged otolith.

Diagnosis by Dix-hallpike – sit patient on the side of the bed, turn patients’ head 45 degrees one way and lie the patient down so the head is below the table.  +VE if patient gets acute vertigo and torsional nystagmus anticlockwise to right ear or clockwise to left ear.

Which canal?

Posterior – towards undermost ear

Horizontal – horizontal and reverses direction as head is turned from side to side.

Treatment – Epley (Think dix-hallpike + roll!)

Do a Dix-hallpike, then when the patient is lying down and the nystagmus has ceased turn the head to the other side.  Ask the patient to roll onto their side while keeping their head in the same position (they should end up looking at the floor). Then ask them to sit up with their head in the same position. After a few moments repeat the dix-hallpike to see if it has worked!

Heres a video

 

Vestibular Neuritis[neurolabrynthitis]

Caused by unilateral vestibular failure of superior or inferior vestibular nerve.  Nystagmus always goes one way, and is horizontal, fast phase away from affected side.  Main differential is stroke.  Head impulse test is abnormal.

Symptoms can last a week, with balance recovery taking up to a month.  BPV can follow.

 

Head impulse Test [HIT]

Shout “LOOK INTO MY EYES” and jerk their head to the left/right 15 degrees.  People shouldn’t be able to fixate on you if they have a peripheral cause.  If there are corrective saccades on way or another, it is the opposite side that is broken (saccades to left RIGHT VOR abnormality), and it’s a PERIPHERAL cause.   If it’s NORMAL (ie you can’t see any corrective saccades) then you may have a brainstem problem (or you’ve not done the test well.  It’s a bit tricky).

** – The HIT can be abnormal in a lateral medullary stroke too.  To make sure it’s not that. Do skew deviation.  Cover one eye for them, get them to look at a point, uncover that eye and cover the other eye very quickly and swap between the 2.  If one eye moves up or down slightly to correct that is abnormal, and you have to think about a CVA.

GOOD [ie non serious]: ABNORMAL HIT NORMAL SKEW == peripheral.

 

Meniere’s Disease

Inner ear disorder with attacks of vertigo lasting <12 hours, accompanied by tinnitus aural fullness in the affected ear.

Central Causes

Migraine vertigo – can occur as aura, or with the headache.

Vertebrobasilar iscahemia – have this in the back of your mind with odd sensations such as tilt, falling (lateropulsion).  It is typically quite brief.

Cerebellar Infarction – patients cannot stand.  Nystagmus can be in both directions or vertical.  If HIT is NORMAL.  There should also be a problem with DANISH.  Symptoms should be sudden and maximal at onset.

Acoustic Neuroma – look for tinnitus, hearing loss, and subtle deterioration of balance, only occasionally get isolated vertigo on it’s own, symptoms should be insidious in onset and getting worse.

 

Medications

Prochlorperazine [stemetil]

Menieres prophylaxis – betahistine

Migraine prophylaxis – beta blocker, pizotifen, valproate

 

 

 

 

 

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