Approach to dizziness

Dizziness is a common exam topic and a common GP presentation. We often have a laugh at the emergency department when an elderly Greek woman presents with dizziness. It is probably that we know that we will never make the dizziness go away. Many causes of dizziness are benign, however, some of them are serious and can be potentially fatal if missed.

Dizziness means different thing to different people. It is important to clarify what they actually mean by dizziness.

As per usual, John Murtagh attempts to simplify the diagnostic process:

Murtagh's diagnostic model 

Probability diagnosis 

1. - Anxiety-hyperventilation 
2. - Postural hypotension 
3. - Simple faint - vasovagal
4. - Acute vestibulopathy
5. - Benign Paroxysmal Positional Vertigo
6. - Motion sickness
7. - Post head injury
8. - Cervical dysfucntion/spondylosis 

Serious disorders not to be missed

1. Neoplasia

• Acoustic neuroma
• Posterior fossa tumour
• Other brain tumours, primary or secondary.

2. Intracerebral infection (e.g. abscess)

3. Cardiovascular 

• Arrhythmias
• Myocardial infarction 
• Aortic stenosis 

4. Cerebrovascular 

• Vertebrobasilar insufficiency 
• Brain stem infarct (e.g. PICA thrombosis)

5. Multiple sclerosis 

pitfalls (often missed)

1. Ear wax - otosclerosis
2. Arrhythmias
3. Hyperventilation 
4. ETOH and other drugs
5. Cough or micturition syncope
6. Vertiginous migraine/migrainous vertigo
7. Parkinson's disease 
8. Meniere syndrome (overdiagnosed) 
9. Ramsay-Hunt syndrome 
10. Rarities
• Addison disease
• Neurosyphilis
• Autonomic neuropath
• Hypertension 
• Subclavian steal 
• Perilymphtic fistula
• Shy-Drager syndrome 

Seven Masquerades checklists

1. Depression 

2. Diabetes

3. Drugs

4. Anaemia 

5. Thyroid disorder

6. Spinal dysfunction 

7. UTI 

Other resources about dizziness

• http://blogs.brown.edu/emergency-medicine-residency/you-make-me-dizzy-miss-lizzy-hints-for-assessing-acute-dizziness/

Vertebrobasilar insufficiency

Condition

• Vertbrobasilar insufficiency 

Definitions

• TIA syndrome of the posterior circulation 
• A good description of the anatomy of the vertebral arteries and basilar artery on wikipedia 

Main features 

• Sudden onset 
• Usually over the age of 50 
• Has cardiovascular risk factors  
• Symptoms depend on the area of the brain that is affected, but patients can experience: 
• Vertigo 
• Visual field defects (diplopia, hemianopia)
• Auditory phenomena (sudden sensorineural hearing loss) 
• Facial numbness or parenthesis
• Dysphagia, dysarthria, hoarseness
• Syncope (drop attacks)
• Hemisensory extremity symptoms 
• Isolated vertigo symptom is unusual. It usually accompanies other neurological symptoms

Investigations

• Clinic test: **Random glucose**, ECG
• As per any other TIAs  (Fasting lipid, fasting glucose, FBE, UEC, Holter, U/S Carotid)
• MRA for a good image of the posterior fossa or if not available, CTA

Management 

• Refer for hospital admission if happens acutely for better outcome
• Otherwise 
• organise urgent CTB to exclude other pathology 
• if no intracranial haemorrhage, start aspirin
• start anti hypertensive and statin 
• organise ECG, blood test, holter monitor and carotid ultrasound. (ideally within 24 hrs)
• refer to neurologist for a second opinion 

References:

• John Murtagh's general practice 5th edition 
• Wikipedia 

Hyperventilation

Condition

• Hyperventilation 

Main features

• Usually related to anxiety and depression 
• Main symptoms 
• breathlessness
• palpitations
• sweating
• dry mouth with aerophagy 
• agitation 
• fatigue and malaise 
• Other symptoms 
• paraesthesia of the extremities
• perioral paraesthesia
• carpopedal spasm 

Management 

• As per treatment of anxiety or depression 
• reassuring Susan that there is no serious physical underlying cause, but ensure careful follow up 
• Advising susan to consciously slow down her respiratory rate and encouraging her to identify the cause, and the control the rate and depth of her breathing 
• breath into a paper bag

Reference

• RACGP Check program dizziness 2011

Menière syndrome

Condition

• Menière syndrome 

Definition 

• Hydrous of the labyrinth such as intralabyrinthine pressure effect. The most likely cause is an episode of viral labyrinthitis that leaves the labyrinth damaged and liable to bouts of endolymphatic hydrops. 
• Secondary forms related to otosclerosis, trauma and longstanding sensorineural hearing loss are also implicated and recognised. 

History 

• Characterised by paroxysmal attacks of 
• vertigo
• tinnitus 
• hearing loss (fluctuating or progressive) 
• Also possibly characterised by:
• nausea and vomiting 
• sweating and pallor
• Abrupt onset - patient may fall 
• Attacks last at least 20 minutes
• Variable interval between attacks (twice per month to twice per year)
• Examination 
• nystagmus (during at attack, often to side opposite the affected inner ear)
• sensorineural deafness
• caloric test impaired vestibular function 
• Audiometry 
• sensorineural deafness
• loudness recruitment
• electrocochleography 
• characteristic change

Examination 

• Sensorineural deafness
• Horizontal nystagmus 
• Caloric test demonstrates impaired vestibular function
• Electrocochleography: abnormal in Meniere syndrome 
• Normal in between attacks 

Treatment

• Acute management 
• Prochlorperazine 12.5 mg
• Long term management 
• advice to avoid caffeine
• Avoid excessive intake of ETOH and tobacco
• Advice for a low salt diet - this is the mainstay of treatment
• Alleviating anxiety by using appropriate sedation and, preferable counselling such as cognitive behaviour therapy
• Referral for a neurological assessment 
• Prescribing a diuretic to be taken daily. eTG recommends hydrochlorothiazide 25mg orally daily 
• Betahistine is recommended as a vasodilator and it may increase the blood supply to the inner ear, 8 mg to 16 mg orally, 2-3 times daily 
• Introduce to Meniere support group 
• Management if symptoms persist despite treatment
• myringotomy with grommet
• endolymphatic sac decompression 
• labyrinthectomy 

Reference:

1. John Murtagh's General Practice 5th edition

 2. Therapeutic guideline 

Acute peripheral vestibulopathy

Condition

• Acute peripheral vestibulopathy 

Definition 

• Acute vestibular failure is the sudden loss of function in one balance organ 
• The presumptive cause of acute peripheral vestibulopathy is vestibular neuritis (also known as vestibular neuronitis). Recent evidence suggests reactivation of herpes simplex type 1 virus in the vestibular ganglion is responsible 

History 

• Mainly in young adults and middle aged people
• Single attack of vertigo 
• Abrupt onset of persistent vertigo
• Often follows a flu-like illness
• Accompanied by nausea and vomiting
• No hearing loss or tinnitus
• Gradual recovery over days to weeks
• Spontaneous horizontal nystagmus 
• Caloric stimulation confirms impaired vestibular function 

Examination 

• Spontaneous horizontal nystagmus 
• Check ear to exclude suppuration in the middle ear or mastoid cavity 
• Head impulse test (positive test points towards acute vestibular syndrome, click on it to watch a video on youtube) 
• Hallpike maneuvre
• Rhomberg test
• Positive Romberg indicates loss of proprioceptive or vestibular input, support the diagnosis of Romberg test
• Bedside assessment of hearing
• Assessment of gait and preponderance to veer to one or other side

Diagnostic triad

• acute vertigo + nausea + vomiting = vestibular neuritis
• same symptoms + hearing loss +/- tinnitus = acute labyrinthitis

Differential diagnoses

• stroke
• Meniere disease
• BPPV
• Vestibula migraine

Red flags

• acute unaccustomed headache
• inability to stand or walk
• the presence of spontaneous direction changing nystagmus
• spontaneous vertical nystagmus
• a normal head impulse
• the presence of additional focal neurological signs

Treatment

• Short term
• Education: spontaneous resolution usually after 1 week
• Prochlorperazine 12.5 mg 
• Short course of corticosteroids such as prednisolone often helps
• Medium
• vestibular physiotherapy could be considered

Reference:

John Murtagh 5th edition p. 497
Check program ENT Case 4 2011

Benign paroxysmal positional vertigo

Condition

• Benign paroxysmal positional vertigo (BPPV)

Definition 

• Common type of acute vertigo that is induced by changing head position - particularly tilting the head backwards, changing from a recumbent to a sitting position or turning to the affected side
• The underlying cause is unknown. Generally accepted theory of causation is that fine pieces of calcium carbonate present in the utricle and become loose, settle at the bottom of one o f the semicircular canal, and generate endolymphatic movement, causing nystagmus with certain head positions. 

History

• Occurs in clusters that persist for several days 
• Usually a latency period of several seconds following a head movement before symptoms develop, and symptoms subside within 10-60 seconds, usually fewer than 30 seconds. 
• Female to male ration is 2:1
• Attacks are not accompanied by vomiting, tinnitus or deafness (nausea may occur)
• Recurs periodically for several days 

Examination

• Normal hearing and vestibular function 
• Positive hallpike manoeuvre
• Brief latency - usually a brief latency of several seconds before the onset of nystagmus and it usually lasts 10-20 seconds
• Nystagmus - usually torsional but may be horizontal. 
• Reversal- upon sitting after a positive manoeuvre, the direction of nystagmus is reversed for a brief period of time
• Fatigability - repetition of the test will result in less nystagmus each time 
• Normal cranial nerve examination 

Murtagh's diagnostic triad

Treatment

• Re-assurance that this condition usually resolves spontaneously  
• Explanation of avoidance measures 
• Brandt-Daroff exercises (Table 1 from RACGP check program dizziness
• Epley manoeuvre 

• The patient sits on the bed with head slightly extended and turned 45 degrees in the direction that precipitated the vertigo 
• The patient then lies on their back with the head hanging over a pillow placed at the shoulder level 
• From this position, turn the head through 90 degrees to the opposite side and wait 1 minute
• Slowly sit the patient upright with the head in a neutral position and sit still for 10 minutes 

Reference:

• John Murtagh 5th ediation 497
• Check program RACGP 2011 Dizziness

Posterior Fossa Tumour

Posterior fossa tumour has a very different differential in an adult as opposed to a child

Adult

• Cerebella meastases (most common) 
• especially lung cancer and breast cancer
• also melanoma, thyroid malignancies and renal cell cancer
• Haemangioblastoma: most common primary brain tumour
• astrocytomas and medulloblastomas are rare in the posterior fossa of adults (< 1% all tumours) 

Child 

• posterior fossa astrocytoma
• pilocytic astrocytoma : most common 
• brainstem glioma 
• Medulloblastoma 
• Ependymoma
• Atypical teratoid/rhabdoit tumour
• Haemangioblastoma 
• Teratoma 

** Overall 50-55% of all brain tumours in children are found in the posterior fossa**

Reference:

• http://radiopaedia.org/articles/posterior-fossa-tumours

Acoustic Neuroma

Condition

• Acoustic neuroma 

Definition

• Acoustic neuromas are intracranial, extra-axial tumours that arise from the Schwann cell sheath investing either the vestibular or cochlear nerve.

History 

• Unilateral hearing loss
• Tinnitus 
• Headache 
• Balance disturbance 
• Facial weakness
• Facial numbness 
• Lower CN palsy 

The most common presentation is overwhelmingly unilateral hearing loss. Assume anyone presents with sensorineural hearing loss with acoustic neuroma until proven otherwise. The following is a chart from e-medicine, here is the link to the full article

Examination

• occipital pain on the side of the tumour
• VIII nerve damage
• unilateral sensorineural deafness developing gradually over a period of months or years 
• around 5% will have sudden hearing loss
• vertigo which may be quite mild and tinnitus are common 
• caloric paresis may be demonstrable 
• V nerve damage
• depression of corneal reflex occurs early. Facial pain, paraesthesia and numbness develop
• VII nerve damage
• facial weakness is unusual 
• IX, X, XI nerve damage
• rare, presents dysphagia, change in voice, palatal weakness
• Compression effects of large tumours
• on cerebellum - ataxia, loss of coordination on ipsilateral side, nystagmus
• on pons - contralateral hemiparesis
• on aqueduct and 4th ventrcle - raised intracranial pressure e.g. headache 

Investigations

• Audiometry: selective sensorineural hearing loss in the right ear and delayed acoustic reflex (movement of the tympanic membrane in response to intense sound).
• Auditory branstem response: brainwave activity in response to sound, and tests the pathway from the cochlea to the brainstem. This should show an absence of waveforms and an increase in the latency of the fifth wave
• MRI

Murtagh's diagnostic triad

• unilateral tinnitus + hearing loss + unsteady gait = acoustic neuroma 

Treatment

• Referral to Neurosurgeon for excision 

References:

• John Murtagh 5th edition 
• Emedicine 
• gpnotebook.co.uk