Compenso vestibolare

Compenso vestibolare
Attivazione di funzioni complementari che si
sovrappongono alle funzioni di equilibrio compromesse.
Comporta la scomparsa delle asimmetrie statiche e
dinamiche nelle risposte oculari e spinali indotte dalla
lesione.
Possono intervenire interazioni sostitutive visive e
propriocettive.
Recupero funzionale
Restituzione: riparazione completa del danno
Adattamento: modificazione della sensibilità dei recettori
periferici da parte del SNC
Assuefazione: riduzione dell’intensità e della durata delle
reazioni vestibolari soggettive provocate da mismatch
sensoriali. E’ un fenomeno centrale di inibizione della
percezione di stimoli che non hanno significato per il
controllo dell’equilibrio o che sono dannosi
Recupero Funzionale Vestibolare:
scopi
n
Indurre sostituzione sensoriale aumentando l’input
visivo e propriocettivo e modificando il gain del riflesso
vestibolare
n
Supportare il compenso centrale attraverso la plasticità
del sistema vestibolare
n
Incoraggiare la mobilizzazione dei segmenti corporei e
l’equilibrio statico e dinamico
n
Promuovere l’habituation alle vertigini e all’instabilità
n
Rimuovere le componenti psicologiche
Esempio compenso lesione acuta monolaterale
ü
Inibizione internucleare
ü
Shut-down cerebellare
ü
Ricalibrazione dei sottosistemi
Sostituzione sensoriale (sostituzione saccadica, COR, ecc.);
dipende dalla preferenzialità sensoriale del soggetto
Ristrutturazione comportamentale (se lasciata a se stessi spesso
patologica con evitamenti, fobie, ecc.)
ü
ü
Compenso vestibolare
Porta a diversi livelli di recupero:
ü
ü
ü
Sostituzione funzionale: stesso sottosistema
riorganizzato, stesso pattern motorio
Sostituzione sensoriale: cambia il sottosistema sensomotorio, stesso pattern motorio
Sostituzione comportamentale: nuovi comportamenti
motori (ristrutturazione)
Evoluzione della lesione
n
Danno primario (lesione iniziale)
n
Danno secondario (in caso di compenso patologico)
n
Danno terziario (cronicizzazione dei fenomeni adattativi
patologici)
PERCHÈ ALCUNI SOGGETTI COMPENSANO E ALTRI
NO, ANCHE A RELATIVA PARITÀ DI DANNO?
Restor Neurol Neurosci. 2010;28(1):83-90.
Management of the patient with chronic dizziness.
Bronstein AM, Lempert T.
Neuro-otology Unit, Division of Neuroscience and Mental Health, Imperial College London,
Charing Cross Hospital, London, UK. a.bronstein@imperial.ac.uk
In this review we present a pragmatic approach to the patient with
chronic vestibular symptoms. Even in the chronic patient a retrospective
diagnosis should be attempted, in order to establish how the patient reached
the current situation. Simple questions are likely to establish if the chronic
dizzy symptoms started as benign paroxysmal positional vertigo (BPPV),
vestibular neuritis, vestibular migraine, Meniere's disease or as a brainstem
stroke. Then it is important to establish if the original symptoms are still
present, in which case they need to be treated (e.g. repositioning manouvres
for BPPV, migraine prophylaxis) or if you are only dealing with chronic
dizzy symptoms.
Restor Neurol Neurosci. 2010;28(1):83-90.
Management of the patient with chronic dizziness.
Bronstein AM, Lempert T.
Neuro-otology Unit, Division of Neuroscience and Mental Health, Imperial College London,
Charing Cross Hospital, London, UK. a.bronstein@imperial.ac.uk
In addition the doctor or physiotherapist needs to establish if the
process of central vestibular compensation has been impeded due to
additional clinical problems:
- visual problems (squints, cataract operation),
- proprioceptive deficit (neuropathy due to diabetes or alcohol),
- additional neurological or orthopaedic problems,
- fear of falling or psychological disorders.
- neurological gait disorder.
Treatment of the syndrome of chronic dizziness is
multidisciplinary but rehabilitation and simple counselling should be
available to all patients. In contrast, vestibular suppressants or
tranquilisers should be reduced or, if possible, stopped.
Curr Med Res Opin. 2006 Sep;22(9):1651-9.
Restoration of vestibular function: basic aspects and practical advances for
rehabilitation.
Lacour M.
Université de Provence/CNRS, Marseille, France. lacour@up.univ-mrs.fr
FINDINGS: Static deficits, following the loss or disruption of vestibular functions,
are fully compensated; this is explained by the vestibulo-centric theory that suggests
different plastic changes occurring in the vestibular nuclei complexes. In contrast,
dynamic deficits remain poorly compensated; the restoration of dynamic vestibular
functions results from substitution processes and vicarious strategies. The practical
advances in the rehabilitation of vestibular defective patients are as follows:
(1) perform rehabilitation at an early stage;
(2) favour active retraining;
(3) do not use stereotyped rehabilitation programs but adapt exercises to the patients;
(4) examine patients in standardized environments;
(5) use both static and dynamic tests;
(6) avoid drugs with sedative effects (or limit them to the very acute stage only) and
prescribe those accelerating the recovery process (e.g. betahistine dihydrochloride).
CONCLUSION: Recovery of vestibular function is greatest when early active
retraining and adequate pharmacological treatments are used in combination.
J Neurol. 2008 Oct;255(10):1479-82. Epub 2008 Jul 11***
Vestibular neuritis: vertigo and the high-acceleration vestibulo-ocular
reflex.
Palla A, Straumann D, Bronstein AM.
Neurology Department, Zurich University Hospital, Frauenklinikstrasse 26, 8091 Zurich, Switzerland.
Patients after vestibular neuritis (VN) often report persistent
dizziness and disequilibrium. We correlated persistent symptoms with
sustained impairment of the high-acceleration horizontal vestibuloocular reflex as determined by quantitative searchcoil head-impulse
testing (qHIT). In 47 patients, qHIT was recorded 0-60 months and
symptoms assessed with the Yardley Vertigo Symptom Scale short form
> or = 18 months after VN onset.
.
No correlation between the magnitude of high-acceleration
vestibular impairment and the severity of vertigo symptoms was
observed.
The lack of a symptom-qHIT correlation suggests that defective
compensation at a more rostral level in the central nervous system
may be responsible for protracted symptoms in VN patients.
MOTIVAZIONE!!!
Different opinions about weight, body image and physical exercise
It is never too late to start playing!
Laryngoscope. 2002 Oct;112(10):1785-90.
The effect of age on vestibular rehabilitation outcomes.
Whitney SL, Wrisley DM, Marchetti GF, Furman JM.
Department of Physical Therapy, School of Health and Rehabilitation Sciences, University of Pittsburgh,
Pittsburgh, Pennsylvania 15260, USA. whitney@pitt.edu
RESULTS: During the initial evaluation, older adults reported having
statistically greater space and motion discomfort and more severe symptoms on
a scale of 0 to 100. Younger adults had more impaired DGI scores and a higher
proportion of caloric testing abnormalities. After rehabilitation, overall
improvement was seen in both the younger and older populations. There were
no statistical differences between the two groups on the DHI, the DGI,
reported symptoms at discharge, or number of falls. When only the complete
matched-pair data were analyzed, there were no statistically significant
differences between the age groups in the proportion of patients demonstrating
clinical improvement.
CONCLUSION: Age does not significantly influence the beneficial effects
of vestibular rehabilitation for persons with vestibular disorders.
Balance disorders caused by vestibular deficit
Se sintomi vestibolari: rischio di caduta aumenta di 12 volte
“Given the high
prevalence among
the elderly, and the
extraordinary
costs associated
with falls
(exceeding $20
billion annually),
screening for
vestibular
dysfunction could
be a life-saving and
cost-effective
practice.”
Rieducazione Vestibolare
Definizione:
Quando la disabilità è provocata da una disfunzione
(danno quantitativo ma organizzazione centrale
efficiente) l’intervento terapeutico è finalizzato alla
sua correzione riorganizzando le funzioni residue del
paziente.
Riabilitazione Vestibolare
Definizione:
Quando la disabilità è provocata da una lesione
periferica o centrale del SNC l’intervento terapeutico
è finalizzato alla ristrutturazione completa del
sistema ottenendo il recupero funzionale attraverso il
superamento della disabilità, anche mediante ausili
protesici e correzioni dell’ambiente.
Indicazioni al training vestibolare
Lesioni vestibolari stabili con compenso assente o incompleto
üLesioni centrali o miste (periferiche e centrali)
üTraumi cranici (esiti)
üVertigine psicogena lieve (approccio somato-psichico)
üPresbiastasia, prevenzione delle cadute
üDisturbi dell’equilibrio di ndd (approccio empirico)
üLabirintolitiasi (residual dizziness persistente)
üLesioni vestibolari instabili (prehab, habituation)
ü
Scopi del training vestibolare
Aumentare la stabilità dello sguardo
üAumentare la stabilità posturale statica e dinamica
üRidurre i sintomi vertiginosi propriamente detti
üMigliorare lo svolgimento delle ADL
ü
VESTIBULAR TRAINING
Basics of vestibular training exercises:
Rapid head movements in yaw, roll and pitch, eyes open/closed,
with fixation or not
Standing and walking on firm or uneven surfaces, head still or
moving, eyes open/closed, fixating or not
Standing on steady or sway-referenced platform, eyes open with
sway-referenced moving landscape
Saccadic, smooth pursuit and/or full-field optokinetic stimulation
on firm or unstable surfaces
Principi di terapia
Postural Compensation for Vestibular Loss
Fay B. Horak
Vestibular rehabilitation should focus on:
n
n
n
n
n
decreasing hypermetria
decreasing an overdependence on surface
somatosensory inputs
increasing use of any remaining vestibular function
substituting or adding alternative sensory feedback
related to trunk sway
practicing challenging balance tasks on unstable
surfaces (mid freq.)