Clinical Tests for Vestibular Function

1. Clinical Tests for Vestibular Function Dr. Vishal Sharma

2. Nystagmus • Involuntary rhythmical oscillatory movement of eye ball • Vestibular disorders cause jerk nystagmus with slow & fast phases • Direction is given by fast phase

3. Nystagmus Intensity grading (Alexander’s law): 1°  only present when looking towards fast phase 2°  also seen when looking straight 3°  also seen when looking towards slow phase

4. Nystagmus • Vestibular lesion nystagmus gets suppressed by optic fixation & enhanced with its removal with Frenzel glasses • Irritative vestibular labyrinthine lesion: Ipsilateral nystagmus • Paralytic vestibular labyrinthine lesion: Contralateral nystagmus

5. Test for gaze evoked nystagmus

6. Test for gaze evoked nystagmus Examiner’s finger kept 30 cm from pt's eyes in centre. Moved in horizontal & vertical planes.Pt is asked to follow it with his eyes. Keep displacement from midline to maximum of 30° (to avoid physiological end-point nystagmus).

7. Fistula test Transmission of increased air pressure in E.A.C., via middle ear, into inner ear through a labyrinthine fistula causes vertigo + nystagmus towards affected ear. E.A.C. pressure is  by intermittent tragal pressure or Siegelization.

8. Siegalization

9. Sites of labyrinthine fistula 1. Horizontal semicircular canal  Cholesteatoma destruction  Fenestration operation 2. Oval window  Post-stapedectomy 3. Round window membrane rupture

10. Hennebert’s sign False positive fistula sign in absence of labyrinthine fistula. 1.Meniere's disease (fibrosis b/w stapes footplate & utricle) 2. Hyper mobile stapes footplate  Congenital syphilis  Idiopathic

11. False negative fistula sign Negative fistula sign in presence of labyrinthine fistula. 1. Cholesteatoma / granulation covering the labyrinthine fistula 2. Dead Labyrinth 3. Total E.A.C. obstruction (impacted wax)

12. Fitzgerald-Hallpike Bithermal Caloric Test Contraindications: 1. E.A.C. obstruction 2. Ear infection 3. T.M. perforation 4. Bradyarrythmias 5. Labyrinthine sedatives (for 24 hrs)

13. Mechanism Convection current formation in endo-lymph due to temperature gradient → ampullo-petal flow or ampullo-fugal flow due to warm or cold water  activation of Vestibulo-Ocular Reflex → vertigo + horizontal nystagmus

14. Fitzgerald-Hallpike Bithermal Caloric Test

15. Fitzgerald-Hallpike Bithermal Caloric Test

16. Procedure Pt supine + 30° head elevation. Each ear irrigated in turn for 40 sec with warm water at 44°C & then cold water at 30°C. Duration of nystagmus is from start of irrigation to end point of nystagmus. Normal = 90–140 sec Direction of fast component: Cold → Opposite ear; Warm → Same ear

17. Normal Calorigram

18. Canal Paresis Duration of nystagmus with both 44°C & 30°C irrigations in one ear is 30 % less than opposite ear. Seen in same sided peripheral vestibular lesion. C. P. (%) = (R30 + R44) – (L30 + L44) X 100 R30 + R44 + L30 + L44

19. Canal Paresis

20. Directional Preponderance Duration of nystagmus in one direction is 30 % more than opposite direction. Seen in same sided central vestibular lesion & opposite peripheral vestibular lesion. D.P. (%) = (L30 + R44) – (R30 + L44) X 100 R30 + R44 + L30 + L44

21. Directional Preponderance

22. Special cases Same sided canal paresis + same sided directional preponderance: • Acoustic Neuroma Same sided canal paresis + opposite sided directional preponderance: • Meniere’s disease

23. Modified Kobrak's Test E.A.C. irrigated for 60 sec with ice cold water in increasing quantity (5, 10, 20 & 40 ml) till nystagmus is noticed. Nystagmus noticed with: • 5 ml = Normal vestibular labyrinth. • 10 / 20 / 40 ml = Hypoactive labyrinth. • No nystagmus (40 ml) = Dead labyrinth

24. Dundas Grant Cold Air Caloric Test • Done in T.M. perforation as water syringing is contraindicated • Air in coiled copper tube is cooled by pouring ethyl chloride in it • Effluent cool air is blown into E.A.C. to produce vertigo + nystagmus

25. Dix – Hallpike maneuvre(Nylen – Barany maneuvre)

26. Step 1 3

27. Step 2

28. Step 3

29. Steps 1 to 3

30. Step 4

31. Step 3 to 4

32. Dix-Hallpike Manoeuvre 1. Pt in sitting position on a couch. 2. Pt’s head turned 45° towards diseased ear. 3. Pt moved rapidly into supine position with head hanging 30° below couch. Pt’s eyes observed for nystagmus for 1 minute. 4. Pt moved rapidly back into sitting position. 5. Manoeuvre repeated for opposite ear.

33. Nystagmus in B.P.P.V.  Latent period (2–20 sec) before nystagmus  Rotatory  Fixed direction, towards ground (geotropic) Duration < 1 minute due to adaptation Direction reversal on return to sit position Fatiguing on repeating Hallpike maneuver Associated vertigo & autonomic symptoms

34. Epley’s particle repositioning manoeuvre

35. Step 1 3

36. Step 2

37. Step 3

38. Step 4

39. Step 5

40. Step 5 to 6

41. Step 6

42. Step 7

43. Step 8

44. Epley’s Manoeuvre 1. Pt in sitting position on a couch 2. Pt’s head turned 45° towards diseased ear 3. Pt moved rapidly into supine position with head hanging 30° below couch 4. Pt’s head rotated by 90° to opposite side 5. Further 90° head + trunk rotation 6. Pt moved rapidly back into sitting position

45. Epley’s Manoeuvre 7. Pt’s head brought in midline 8. Slight flexion of pt’s head  Cervical collar given to pt for 48 hours  Pt to sleep in 30o head end elevation & avoid violent head jerks  Pt must have nystagmus at every step of Epley’s manoeuvre if it is done properly

46. Thank You