DIZZINESS - A PRACTICAL APPROACH
  •  Common complaint

 Diagnosis is usually made on:Assessment is often daunting & challenging

  • history
  • history
  •  history

Diagnosis is usually confirmed by:

  • Physical Examination
  • Investigations

Eg: Benign Paroxysmal Positional Vertigo (BPPV)

 

!!! KEY: History begins by trying to understand what the patient means by "dizziness" !!!

 

Vertigo

Dysequilibrium

Light-headedness

Vertigo

  • Defn: illusion of motion
  • Subjective vs Objective
  • Types:
  • Rotatory (? SCC problem)
  • Linear (? Otolith organ problem)
  • Floating

Dysequilibrium

  • Defn: inability to maintain the centre of gravity
  • "On a boat"
  •  Imbalance, falling, stumbling
  • Cause:
  • Vestibular (peripheral or central)
  • Non-vestibular
    • Sensory (propriocetn/senstn)
    • Motor (muscle weakness/arthritis

Light-headedness

 

  • Defn: similar symptoms to those preceding syncope

Eg: sitting up quickly

Cause:

  • NOT Vestibular
  •  ? Cardiac, Vascular (VBI), vaso-vagal, metabolic, hyperventilation

?? Try to simulate by hyperventilating

The History

 

"I understand you have been referred to me because you have dizziness, please tell me what you feel when you have this sensation and let us not use this word"

 

Attack characteristics

  • Initial attack: date/duration/nature
  • Last attack : date/duration (secs min hrs) /nature
  • Frequency: per day/week/month
  • Precipitating factors: causal event/position/exertion
  • Relieving factors: position/medn
  • Associated Symptoms

Otologic symptoms

  • Hearing loss
  • Tinnitus
  • Ear Fullness/Pressure

Non-Otologic symptoms

  • Visual disorientation (loss of visual cues)
  • Intolerance of visual motion
  •  Disruption of focusing & depth perception
  • Oscillopsia: movement of horizon with walking (eg video recorder)
  • Neurologic: headaches (migranous vertigo)
  • weakness, numbness, seizures (vascular, tumours, MS)
  • Psychiatric: anxiety, hyperventilation, halluc’n (not usually vertigo)
  • Cardiac: palpitations
  • Autonomic: dysautonomia may => postural hypotension
  • Degenerative: presbystasis
  • Metabolic

CLUES TO Diagnosis IF VERTIGO (ie Duration of VERTIGO)

  • Seconds (5-90 secs): Benign Paroxysmal Positional Vertigo
  • Minutes (2-20mins): Vascular (usually assoc with other symptoms) (?? Under-reported)

                                              Non Vascular

  • Hours (20 mins-24hrs): Meniere’s Disease (usually 4-8 hours)

                                                    Migraine

                                                    Acoustic Neuroma (? Infarction of nerve)

                                                    (Tip: telephone positive sign)

  • Days: Strongly suspect Vestibulo-Neuro-Labyrinthitis (VNL)

 NB: Perilymphatic fistula: any of above, usually assoc’d with hearing loss)   

 

EXAMINATION OF THE DIZZY PATIENT

General Examination: PR, BP, Temp

ENT, Head & Neck Examination

Neurotologic Exam (Balance Testing):

Fistula Test

Eyes: Smooth Pursuit, Nystagmus, Head Shake, Snellen's oscillopsia

Gait

Romberg

Unterberger

Hallpike

Other Tests of co-ordination

EYES:

Smooth Pursuit:

- allows clear continuous vision of moving objects

- Test: target 1 m from pt

- If Ab(N) => ? B/Stem or cerebellar

medn’s: BZ’s, Anticonvul, Li

Saccadic Eye Movement:

- Test: 2 objects 1m away, 150 apart

- If Slowing: INO (B/S , MS)

- If Inaccurate: cerebellum

- Prob initiating: Parkinson’s

Nystagmus:

Direction = Fast Phase

Plane

Types: Spontaneous: Primary Gaze or <300 from midline

(Remember: End Point Nystagmus)

Evoked: Head shake, Positioning

Vestibular = "direction fixed" (vs Central)

? Side of Vestibular Lesion:

Acute Hypofunction (cut vestib nerve) = FAST PHASE C/LATERAL

Chronic Lesion (usually htpofunction) = FAST PHASE C/LATERAL

Acute Irritative lesion (VNL) = FAST PHASE IPSILATERAL

Snellen’s Oscillopsia:

  •  Sensitive test for vestibular lesion
  • Test: read Snellen's chart with head stationary then read with 60 deg head rotation (1-2 cycles/sec)
  • (N) = degrade by 1 line
  • Unilateral loss = degrade by 2-4 lines
  • Bilateral loss = degrade by 5-6 lines
  •  Good test for monitoring ototoxic medications

GAIT

Questions ??

    •  Is the gait relatively normal ?
  •  Does the patient require assistance to walk stand ?
    • wide based (? cerebellar disorder)
    • shuffling (? Parkinson’s)
    • (?exaggerated ???? malingering)
  • Does the patient veer into wall ? (vestibular / cerebellar)

ROMBERG TEST

Sharpened (or Tandem) Romberg

Tests: dorsal white column & vestibular

UNTERBERGER (FUKUDA) TEST

Marching, eyes closed, arm extended

Positive if >45 deg turn in 50 steps

Good vestibular test

HALLPIKE TEST

Test of BPPV

Positive if: nystagmus +/- subjective vertigo

 

INVESTIGATIONS

  • Audiogram (pure tone & speech discrimination)
  • Vestibular Function Tests (VFT’s)
    • Electronystamography (ENG)
    •  Rotational Chair
    •  Posturography
    • Electrocochleography (ECoG).. If suspect MD

Imaging

If suspect a central lesion on Hx & Exam

Atypical clinical features

Asymmetry on above investigations

MRI & MRA (with Gadolinium)…. Soft tissue lesion

CT Petrous Temporal Bones…. Bony lesions

Bloods (rarely)

TRANSCRANIAL DOPPLER

  • emits a signal => reflected off moving RBC’s
  • magnitude of change in frequency = velocity

STENOSIS

increase in blood flow velocity to allow same volume of blood to pass through

 

DIZZINESS – SUMMARY

(VDLMOP)

Vertigo

Dysequilibrium

Light-headedness

Multisensory Dizziness

Migraine Variant

Ocular Dizziness

Oscillopsia

Psychological Dizziness

Physiologic Dizziness