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Early Rehabilitation Using Head Impulse Test for Acute Vestibular Deficit

Not Applicable
Recruiting
Conditions
Vestibular Schwannoma
Unilateral Vestibular Deficit
Registration Number
NCT06660082
Lead Sponsor
Hospices Civils de Lyon
Brief Summary

The vestibulo-ocular reflex (VOR) induces a compensatory movement in the eye when the head is rotated, to maintain stable vision when we move. It originates in the peripheral vestibular system, which detects head movements. It is particularly effective for rapid head movements, as tested in the Head Impulse Test (HIT). In acute unilateral vestibular deficit (AUVD), the VOR deficit is compensated for by a substitution saccade, more commonly known as catch up saccade, that contribute to refocus the gaze and maintain vision during head rotations.

Recent technological advances have made it possible to make high-quality recordings during HIT (video Head Impulse Test, vHIT), leading to the identification of substitution saccades of variable latency. Our team has shown that saccades of shorter latency lead to better visual function (Hermann et al., 2017) and that the cerebellum is involved in the development of these saccades (Hermann et al., 2023), suggesting a learning effect rather than the de novo appearance of particular saccades.

The main hypothesis of this study is that the mechanisms underlying short-latency substitution saccades, which seems to guarantee good functional recovery, depend on learning occurring from the first days after an acute unilateral vestibular deficit. We also hypothesise that early physiotherapeutic rehabilitation of the VOR under Head Impulse Test conditions would promote this learning process and the development of early catch-up saccades.

One of the causes of AVD is the resection of cochleovestibular schwannomas. This procedure involves a neurotomy, i.e. complete vestibular deafferentation, which is precisely known due to the scheduled nature of the surgery. The exact moment of onset of vestibular damage is therefore known, unlike other vestibular pathologies. Hospitalisation is necessary in the immediate aftermath of surgery, with the presence of physiotherapists on the wards. In addition, there is no spontaneous recovery of the vestibular deficit. These patients therefore represent the ideal acute unilateral vestibular deficit model for testing our hypothesis. Two studies using vHIT in the aftermath of vestibular schwannoma resection surgery (Pogson et al. 2022; Mantokoudis et al. 2014) also allow us to confirm the safety and feasibility of our protocol in this patient population.

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
26
Inclusion Criteria
  • patients with unilateral vestibular schwannoma and programmed surgery

  • vestibulo-ocular reflex gain :

    • on pathological side > 0.50
    • on healthy side > 0.80
  • all information's concerning the study given more than 15 days before surgery and consent collected the day before surgery

Exclusion Criteria
  • Radiotherapy treatment prior to surgery.
  • Resumption of surgery
  • Presence of bilateral vestibular schwannomas
  • Normal or Corrected to normal distance visual acuity < 5/10
  • Presence of other aetiologies that may explain the ataxic syndrome and/or oscillopsias
  • Oculomotor paralysis, ocular instability in primary position
  • Use of medications that compromise eye movement (psychotropic drugs)
  • Cervical spinal pathology with instability (contraindication for vHIT)
  • Cochlear implantation
  • Non-stabilized medical condition
  • Pregnant women. This exclusion criterion will be investigated by questioning the patient.
  • Patient under guardianship
  • Patient not affiliated to a social security scheme
  • Patient participating any other interventional study

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Primary Outcome Measures
NameTimeMethod
First Substitution Saccade Latency after treatmentDay 7

Mean latencies (in milliseconds) of the first substitution saccade assessed by vHIT examination, in both groups.

Eye movements are recorded during the vHIT examination, carried out by one of the expert practitioners (physiotherapist or doctor) investigating the study. Data from the vHIT are extracted, enabling offline analysis of oculomotor parameters, including the latency of the first substitution saccade in milliseconds. These analyses are carried out off-line by the principal investigator, who was trained and experienced in this type of analysis, using software that allowed standardised and automated analysis, blinded to the group.

Secondary Outcome Measures
NameTimeMethod
First Substitution Saccade Latency during the First WeekEveryday from post-surgery Day 1 to Day 6

Mean latencies (in milliseconds) of the first substitution saccade assessed by vHIT examination, in the experimental group.

This secondary outcome measure is analysed using the same method described for Main Outcome

First Saccade Latency after treatment (follow-up)At post-surgery Day 45 and 3rd month

Mean latencies (in milliseconds) of the first substitution saccade assessed by vHIT examination, for both groups

This secondary outcome measure is analysed using the same method described for Main Outcome

First saccades amplitude after treatmentPost surgery Day 7, Day 45 and 3rd month

Mean amplitudes (degrees) of the first substitution saccade assessed by vHIT examination, in both groups.

Eye movements are recorded during the vHIT examination, carried out by one of the expert practitioners (physiotherapist or doctor) investigating the study. Data from the vHIT are extracted, enabling offline analysis of oculomotor parameters, including the amplitude of the first substitution saccade in milliseconds. These analyses are carried out off-line by the principal investigator, who was trained and experienced in this type of analysis, using software that allowed standardised and automated analysis, blinded to the group.

First saccades amplitude during first weekEveryday from post-surgery Day 1 to Day 6

Mean amplitudes (degrees) of the first substitution saccade assessed by vHIT examination, in the experimental group

This secondary outcome measure is analysed using the same method described for Main Outcome.

Balance and gait assessmentAt Day -1 (pre-surgery), and post-surgery Day 7, Day 45 and 3rd Month

Score of the modified Dynamic Gait index (m-DGI), in both groups.

Quality of Life AssessmentAt Day -1 (pre-surgery), and post-surgery Day 7, Day 45 and 3rd Month

Score of the self administered Dizziness handicap Inventory (DHI), in both groups.

Trial Locations

Locations (1)

Pierre Wertheimer Hospital - Neurological Hospital

🇫🇷

Bron, France

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