A Practical approach to the assessment of a dizzy patient

1. A Practical approach to the assessment of a dizzy patient Tim Price Consultant ENT Surgeon Yeovil and Dorchester

2. Definitions • Vertigo – • “an hallucination of movement”

3. Definitions • Nystagmus – • involuntary oscillatory eye movement • Central disorder (vertical) • Peripheral (horizontal) • Slow labyrinthine component • Fast correcting cerebral component • Named after the direction of fast movement. • Three degrees of severity

4. Anatomy and Physiology

5. Membranous Labyrinth

6. Anatomy and Physiology • Semicircular canals - angular acceleration

7. Saccule & utricle - linear acceleration. • Saccule – vertical. • Utricle – horizontal.

8. Impulses fed into brainstem • Integrated with vision and proprioception. • 70% visual input • 15% proprioception • 15% vestibular • Little input to cerebral cortex.

9. Cortex, cerebellum, reticular formation, extra-pyramidal system Cortical awareness of head/body/motion Control of oculomotor activity Vision Balance Labyrinthine activity Control of posture Proprioception, Superficial sensation Control of motor skill

10. Pathology and Clinical syndromes. • Non-vestibular disorders: • cardiovascular • metabolic • musculoskeletal • ocular disease.

11. Pathology and Clinical syndromes. • Examples include: • vertebrobasilar insufficiency • postural hypotension • cervical vertigo • iatrogenic vertigo • non-organic or psychological causes

12. Pathology and Clinical syndromes. • Vestibular disorders: • central • peripheral include: • BPPV • Meniere’s • Acute vestibular failure- trauma or infection {bacterial or viral(Vestibular neuronitis/ Labyrinthitis)} • acoustic neuromas • cholesteatoma

13. History • Of paramount importance in making the diagnosis. • Dx. 70%! • Important to identify symptoms not attributed to the vestibular system

14. History • A full description of the sensation • Onset • precipitating factors (Head position, head movement, movement in general, Visual stimuli, Pressure changes, Food, Menses). • associated symptoms • frequency and duration of attacks

15. History Frequency/timing Seconds BPPV, SSCCD, cardiac Minutes to hours Meniere’s, migraine, TIA Hours to days Migraine, CVA, vestibular neuritis Days to weeks Migraine, vestibular neuritis, CVA Months to years CVA, ototoxic, multisensory dysequilibrium, psychiatric

16. Otologic History • Hearing – loss or hyperacusis • Tinnitus • Aural fullness • Ear pain or discharge

17. History • Previous history of trauma • Previous medical history- Cardiac Vascular risk factors Endocrine – thyroid, diabetes Autoimmune Psychiatric

18. Medication- Centrally acting drugs New drugs Blood pressure treatment Diabetic Thyroid Exposure to ototoxic drugs • Alcohol

19. Examination (10-20%) • Normal ENT examination • Ear + fistula test • Cranial nerves

20. Examination • Cranial nerves

21. Test of vestibulo-ocular reflex • Nystagmus • Head Shake • Head thrust

22. Tests of VOR • Dynamic Visual Acuity • Positional testing- Dix-Hallpikes Test/Maneuver

23. Central Oculo-motor exam • Eyes - Gaze • Smooth Pursuit. • Fixation Suppression. • Cerebellum • past pointing • dysdiadochokinesis

24. Test of vestibulospinal reflex • Gait • Rhombergs • Unterbergers stepping test

25. Examination • Blood pressure- lying and standing

26. Investigation (10-20%) • Audiometry • Vestibular function tests • caloric tests • ENG • MRI

27. Rules of thumb • If symptoms are more prominent than signs, then most likely vestibular • If signs are more prominent than symptoms, then most likely central • If you can’t get the diagnosis in the first 5 minutes, then there probably isn’t one • Bizarre history needs signs, otherwise usually not organically diagnosable cause

28. Thank you • Any Questions?