functiestoornissen van het evenwichtssysteem: een wereld van onbegrip

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Sharon Sutton
6 years ago
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1 functiestoornissen van het evenwichtssysteem: een wereld van onbegrip Herman Kingma, department of ORL, Maastricht University Medical Centre Maastricht Research Institute Mental Health and Neuroscience

2 vestibular pathology (traditional view): key symptom: vertigo peripheral loss: unilateral: central compensation the other labyrinth takes over

3 not always vertigo in case of vestibular loss slow unilateral loss (vestibular schwannoma) no vertigo or nystagmus

4 not always vertigo in case of vestibular loss slow unilateral loss (vestibular schwannoma) no vertigo or nystagmus what happens in case of a acute bilateral loss?

5 May 2008 Mans Magnusson Michael Karlberg Lund, Sweden Lidocaine 2 mg /ml

6 Topical prilocaine (EMLA) on eardrums Intratympanal injection of lidocaine (spinal tap needle)

7 1. Right side

8 2. Left side

9 3. Wait and see

10 30 minutes later

11 returning from the toilet after severe vomiting

13 - duration 8 hours - reproducible

14 acute bilateral vestibular loss no vertigo no spontaneous nystagmus no auditory symptoms severe unsteadiness / ataxia intolerance for voluntary head movements clear neuro-vegetative symptoms

15 take home message 1 only in case of acute asymmetries - vertigo and nystagmus slow unilateral, slow or acute bilateral loss - no vertigo or nystagmus

16 the other labyrinth takes over? any chronic complaints related to losing the vestibular sense?

17 gravitoreceptors blood pressure sensors in large blood vessels labyrinths autonomic processes fast blood pressure regulation heart beat frequency nausea / vomiting Vestibular effects on cerebral blood flow Serrador et al, BMC Neuroscience 2009 somatosensory e.g. foot sole pressure CNS interpretation learning adaptation compensation vision hearing circadian rhythm vestibular projections hypothalamus supra-chiasmatic nucleus Vestibular modulation of circadian rhytm Fuller et al, Neuroscience image stabilisation balance control spatial orientation

18 gravitoreceptors blood pressure sensors in large blood vessels labyrinths autonomic processes fast blood pressure regulation heart beat frequency nausea / vomiting Vestibular effects on cerebral blood flow Serrador et al, BMC Neuroscience 2009 somatosensory e.g. foot sole pressure CNS interpretation learning adaptation compensation vision hearing circadian rhythm vestibular projections hypothalamus supra-chiasmatic nucleus Vestibular modulation of circadian rhytm Fuller et al, Neuroscience image stabilisation balance control spatial orientation

vestibular impact upon postural control - regulation of muscle tone relative to gravity - regulation of COM relative to base of support balancing correction

19 vestibular impact upon postural control - regulation of muscle tone relative to gravity - regulation of COM relative to base of support balancing correction steps - labyrinths important for detection of gravity-vector fast vestibulo-spinal corrections learning complex motor activities Centre Of Mass base of support

20 visual cortex cer hippocampus basal ganglia spinal pattern generator Frontal cortex: initiation, dual tasks Cerebellum: rhythm and velocity Basal: ganglia modulation Brainstem: start and stop Spinal cord: automatic spinal patterns (running) Labyrinths: keep muscle tone + body position in line with gravity (fast VSR) vn

darkness - in presence of optokinetic stimuli labyrinths less relevant for: walking with visual anticipation and

21 otolith function especially relevant in case of: motor learning (retardation in congenital areflexia) maintaining postures that need fast control towardsgravity when other senses are compromised; - soft surface (wind-surfing) - in darkness - in presence of optokinetic stimuli labyrinths less relevant for: walking with visual anticipation and without unexpected disturbances bilateral areflexia leads to degeneration of head direction and head place cells in the hippocampus

patient with severe bilateral vestibular hyporeflexia stop walking when talking: predictor of falls slow tandem walk fast tandem walk - no fast control of muscle tone -

22 patient with severe bilateral vestibular hyporeflexia stop walking when talking: predictor of falls slow tandem walk fast tandem walk - no fast control of muscle tone - focuss on visual anticipation - no fast control of body orientation - only using feed forward - only slow proprioceptive + visual feed back - no fast feed back available

23 complaints related to vestibular dysfunction acute loss or fluctuating function transient: vertigo, nausea, falling / imbalance remaining peripheral vestibular function loss sustained: - reduced ability for fast corrections of balance

gravitoreceptors blood pressure sensors in large blood vessels labyrinths autonomic

effects on cerebral blood flow Serrador et al, BMC Neuroscience 2009 somatosensory e.g.

circadian rhythm vestibular projections hypothalamus supra-chiasmatic nucleus Vestibular

24 gravitoreceptors blood pressure sensors in large blood vessels labyrinths autonomic processes fast blood pressure regulation heart beat frequency nausea / vomiting Vestibular effects on cerebral blood flow Serrador et al, BMC Neuroscience 2009 somatosensory e.g. foot sole pressure CNS interpretation learning adaptation compensation vision hearing circadian rhythm vestibular projections hypothalamus supra-chiasmatic nucleus Vestibular modulation of circadian rhytm Fuller et al, Neuroscience image stabilisation balance control spatial orientation

25 cortex cgl thal cmes pons cer omn vn VOR: 8 msec OKR and Smooth pursuit: >75 msec

26 head impulse test in unilateral loss standard video (50 Hz)

27 the German experience: the other labyrinth does not take over loss of gaze stabilisation (towards bad-side) especially for fast head movements

28 head impulse test in bilateral loss CASIO Exilem: high speed recording (300 Hz)

29 simulation of oscillopsia reduced dynamic visual acuity in case of bilateral vestibular areflexia

30 Dynamic Visual Acuity (VA) measurement treadmill: 2, 4 and 6 km/hr

31 decrease of VA during walking normal values (maximum VA decrease)

32 which major chronic complaints are related to vestibular deficits?

33 acute asymmetries: - vertigo, imbalance, nystagmus permanent loss: - reduced ability for fast balance correction (need for visual anticipation and constant attention) - reduced dynamic visual acuity (intolerance to fast movements of the head or visual stimuli) - secondary: fear and fatigue (cognitive load) the other labyrinth does NOT take over

34 take home message 2 the other labyrinth does not take over vestibular function loss implies permanent impairment

35 need for new tests to quantify function loss and impairment VEMP, VHIT, DVA, vestibular thresholds

36 need for vestibular protheses especially in case of bilateral losses vibrotactile feed back, VI Maastricht Balancebelt

37 prevalence of severe bilateral loss (US): 80/ e.g. presbyo-vestibulopathy (Della Santina et al. 2009) patients with acquired severely reduced bilateral vestibular function do suffer and need treatment (Guinand et al. 2012) role for a substitution system or implant (v.d. Berg et al, 2011)

38 miniature 6-DOF detector in the belt 4x30x40 mm (gyroscopes + accelerometers) vibration belt on the trunk 12 vibrators battery + processor with zero-posture reset

39 belt with vibrators sensor random sensor on placebo effect? double blind placebo controlled study

vibrotactile vest and belt: supports body tilt and body rotation perception effect significant more than placebo in 64 out of 83 patients vibrotactile feed back improves automation of

40 vibrotactile vest and belt: supports body tilt and body rotation perception effect significant more than placebo in 64 out of 83 patients vibrotactile feed back improves automation of balance and gait 1 system is now used > 4 years: patient reports increase in quality of life new adjustable system allows easy testing in patients if they experience any benefit vest adjustable belt

41 increased perception of body tilt and body rotation 5 patients are now provided with an individually custumized belt for long term ambulatory evaluation (study sponsored by MUMC+)

42 take home messages 1. vestibular loss occurs frequently without vertigo: recognise the sensory deficit symptoms 2. the other labyrinth does not take over: vestibular loss leads to permanent impairment 3. vestibular protheses are on their way...

43 thank you for your kind attention

met het oog op evenwicht

met het oog op evenwicht Herman Kingma, Department of ORL, Maastricht University Medical Centre Faculty of Biomedical Technology, Technical University Eindhoven problems in patients with dizziness and