Early Rehabilitation Using Head Impulse Test for Acute Vestibular Deficit

NCT ID: NCT06660082

Last Updated: 2025-05-16

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 26 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-05-13
• Study Completion Date: 2027-05-31

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.

Conditions

Vestibular Schwannoma; Unilateral Vestibular Deficit

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: DOUBLE

Study Groups

Experimental Group

Participants included in this group will undergo experimental treatment as described below.

Head movements

Group Type: EXPERIMENTAL

Experimental treatment: Head movements

Intervention Type: PROCEDURE

These are gaze stabilisation exercises under vHIT control, between post-operative days 1 to 6.

The patient sits facing a wall 2 metres away. The investigator places the vHIT device on the participant's head and ensures that it fits properly.

This is followed by an initial calibration phase (the patient must follow a laser dot with his eyes).

Then comes stimulation phase: the investigator, standing behind the patient, places his hands on the sides of the patient's lower jaw, which he is asked to clench. The investigator asks the subject to stare at a visual target on the wall in front of the patient. The investigator then performs a series of low-amplitude, high-speed head movements in the plane of the lateral canals and on the side of the vestibular deficit.

The patient is encouraged to resume fixation of the visual target as quickly as possible.

For each treatment session, patients should perform a minimum of 10 impulses and a maximum of 30 impulses on the deafferented side. Each

Control Group

Participants included in this group will undergo sham-treatment as described below.

Eye movements without head movements

Group Type: SHAM_COMPARATOR

Sham treatment: only eye movements

Intervention Type: PROCEDURE

These are visually guided saccade exercises under vHIT device control but without head movements (saccade module), between post-operative days 1 to 6.

For this sham treatment, the modalities are identical to the experimental treatment session, up to the calibration phase described above.

For the stimulation phase, the investigator, standing behind the patient, places his hands on the sides of the patient's lower jaw, which he is asked to clench. The investigator asks the subject to stare at a visual target on the wall in front of the patient. The target then jumps horizontally to trigger visually guided saccades or slides horizontally to trigger an eye-tracking movement. The investigator stabilises the patient's head to prevent any head movement. The patient is encouraged to resume or maintain fixation of the visual target as quickly as possible.

A minimum of 5 horizontal saccade sequences and 5 horizontal eye-tracking sequences will be performed. Each training session lasts approxi

Interventions

Experimental treatment: Head movements

These are gaze stabilisation exercises under vHIT control, between post-operative days 1 to 6.

The patient sits facing a wall 2 metres away. The investigator places the vHIT device on the participant's head and ensures that it fits properly.

This is followed by an initial calibration phase (the patient must follow a laser dot with his eyes).

Then comes stimulation phase: the investigator, standing behind the patient, places his hands on the sides of the patient's lower jaw, which he is asked to clench. The investigator asks the subject to stare at a visual target on the wall in front of the patient. The investigator then performs a series of low-amplitude, high-speed head movements in the plane of the lateral canals and on the side of the vestibular deficit.

The patient is encouraged to resume fixation of the visual target as quickly as possible.

For each treatment session, patients should perform a minimum of 10 impulses and a maximum of 30 impulses on the deafferented side. Each

Intervention Type: PROCEDURE

Sham treatment: only eye movements

These are visually guided saccade exercises under vHIT device control but without head movements (saccade module), between post-operative days 1 to 6.

For this sham treatment, the modalities are identical to the experimental treatment session, up to the calibration phase described above.

For the stimulation phase, the investigator, standing behind the patient, places his hands on the sides of the patient's lower jaw, which he is asked to clench. The investigator asks the subject to stare at a visual target on the wall in front of the patient. The target then jumps horizontally to trigger visually guided saccades or slides horizontally to trigger an eye-tracking movement. The investigator stabilises the patient's head to prevent any head movement. The patient is encouraged to resume or maintain fixation of the visual target as quickly as possible.

A minimum of 5 horizontal saccade sequences and 5 horizontal eye-tracking sequences will be performed. Each training session lasts approxi

Intervention Type: PROCEDURE

Other Intervention Names

Head movements

Eligibility Criteria

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

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Hospices Civils de Lyon

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

Pierre Wertheimer Hospital - Neurological Hospital

Bron, , France

Site Status: RECRUITING

Countries

France

Central Contacts

LAGADEC VL VINCENT

Role: CONTACT

Vincent.lagadec@chu-lyon.fr

0033643537713

HERMANN RH Ruben, MD

Role: CONTACT

ruben.hermann@chu-lyon.fr

Facility Contacts

LAGADEC VINCENT

Role: primary

Vincent.lagadec@chu-lyon.fr

00336.43.53.77.13

Other Identifiers

2024-A02268-39

Identifier Type: OTHER

Identifier Source: secondary_id

69HCL24_0718

Identifier Type: -

Identifier Source: org_study_id