Covert Saccade Triggers in Bilateral Vestibular Hypofunction

NCT04268615 | Completed

• 2 other identifiers: 69HCL19_09982020-A00184-35
• Study Type: interventional
• Target: 32
• Locations: 1 country
• Sites: 1

Brief Summary

Patients with chronic bilateral vestibular hypofunction may suffer from a visual instability during head movement called oscillopsia. Visual consequence of vestibular deficit can lead to a severe impairment of their quality of life. However, correcting saccades during rapid head movement, called covert-saccades, have been more recently identified. These saccades, which occur during the head movement in patients with vestibular hypofunction, present a very short latency. They could compensate for the lack of vestibular-ocular reflex and greatly decrease oscillopsia and visual impairment. The triggering of these covert-saccade is still not known. They could be of visual origin but the short latency is unusual. The objective of this study is to evaluate the potential role of visual trigger in 12 patients with chronic bilateral areflexia, using different visuo-vestibular conditions. The latency of simple visually guided saccades will also be tested in the group of patients and a group of 12 healthy controls.

Conditions

Reflex, Abnormal; Bilateral Vestibulopathy; Healthy Volunteers

Keywords

Saccadic Eye Movements; Bilateral Vestibulopathy; Bilateral Vestibular Hypofunction

Outcome Measures

Primary Outcomes (1)

• Latency of covert-saccades

  Latency of covert saccades correspond to the time between the beginning of head impulse and the initiation of the first covert-saccade

  Day 1

Secondary Outcomes (4)

• Frequency of covert-saccades

  Day 1

• Velocity of covert-saccades

  day 1

• Amplitude of covert-saccades

  Day 1

• Latency of visually-guided saccades

  Day 1

Study Arms (2)

Patients

EXPERIMENTAL

Patients suffering from chronic bilateral vestibular hypofunction

Other: Covert Saccades and Virtual Reality; Other: Actives versus passives Head Impulses; Other: Visually guided saccades

healthy subject group

ACTIVE COMPARATOR

Other: Covert Saccades and Virtual Reality; Other: Actives versus passives Head Impulses; Other: Visually guided saccades

Interventions

Covert Saccades and Virtual Reality OTHER

During this intervention, patients will undergo head impulse testing while wearing virtual reality Headsets. During the head impulse tests the visual information will be modified in order to create a conflict between head rotation and rotation of the visual scene. Recording of head and eye movement will be done during these head impulses in order to verify if visual information modifies compensatory eye movements during head impulses.

Patients; healthy subject group

Actives versus passives Head Impulses OTHER

Patients will undergo classic passive head rotation as well as active head rotation in order to compare latencies of covert saccades in both conditions.

Patients; healthy subject group

Visually guided saccades OTHER

Patients as well as healthy control subjects will undergo testing of visually guided saccades in different conditions (step, gap, overlap) in order to compare latencies of covert saccades between both groups.

Patients; healthy subject group

Eligibility Criteria

• Age: 18 Years - 90 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• For all :
• Age from 18 to 90
• Understanding of the experimental instructions
• Informed Consent
• For Patients :
• Bilateral vestibular hypofunction with regards to the criteria of the of the Barany Society A. Chronic vestibular syndrome with at least three of the following symptoms
• Postural imbalance
• Unsteadiness of gait
• Movement-induced blurred vision or oscillopsia during walking or quick head/body movements
• Worsening of postural imbalance or unsteadiness of gait in darkness and/or on uneven ground B. No symptoms while sitting or lying down under static conditions C. Bilaterally reduced or absent angular VOR function documented by
• bilaterally pathological horizontal angular VOR gain \< 0.6, measured by the video-HIT5or scleral-coil technique and/or
• reduced caloric response (sum of bithermal max. peak SPV on each side \< 6°/sec7)and/or
• reduced horizontal angular VOR gain \< 0.1 upon sinusoidal stimulation on a rotatorychair (0.1 Hz, Vmax = 50°/sec).
• D. Not better accounted for by another disease
• \* For Healthy control No ENT or neurological disorders

You may not qualify if:

• Corrected Visual Acuity lower than 5/10
• Other conditions leading to oscillopsia or ataxia
• Oculomotor palsy, ocular instability in primary position
• Treatment that may affect ocular motility (psychotropes)
• Cervical rachis pathology with instability
• Cochlear Implants
• Non-stabilized medical disease
• Pregnant women
• Patients under tutelage
• Patient without social security

Sponsors & Collaborators

• Hospices Civils de Lyon: lead

Study Sites (1)

Hospices Civils de Lyon

Bron, 69500, France

Location

Related Publications (3)

• Lagadec V, Pelisson D, Koun E, Robert C, Froment Tilikete C, Hermann R. Oculomotor compensatory strategies in bilateral vestibulopathy: Predictive and active conditions of head movements. J Vestib Res. 2025 Nov;35(6):290-299. doi: 10.1177/09574271251355180. Epub 2025 Jun 21.

  PMID: 40543046 BACKGROUND

• Hermann R, Ramat S, Colnaghi S, Lagadec V, Desoche C, Pelisson D, Froment Tilikete C. Catch-Up Saccades in Vestibulo-Ocular Reflex Deficit: Contribution of Visual Information? Ear Hear. 2025 May-Jun 01;46(3):719-728. doi: 10.1097/AUD.0000000000001616. Epub 2024 Dec 18.

  PMID: 39690450 BACKGROUND

• Desoche C, Verdelet G, Salemme R, Farne A, Pelisson D, Froment C, Hermann R. Virtual reality set-up for studying vestibular function during head impulse test. Front Neurol. 2023 Mar 29;14:1151515. doi: 10.3389/fneur.2023.1151515. eCollection 2023.

  PMID: 37064179 BACKGROUND

MeSH Terms

Conditions

Reflex, Abnormal; Bilateral Vestibulopathy

Condition Hierarchy (Ancestors)

Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Vestibular Diseases; Labyrinth Diseases; Ear Diseases; Otorhinolaryngologic Diseases

Study Officials

• Caroline FROMENT, MD

  Hospices Civils de Lyon

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 11, 2020
• First Posted: February 13, 2020
• Study Start: December 15, 2020
• Primary Completion: March 21, 2022
• Study Completion: March 21, 2022
• Last Updated: September 2, 2025

Record last verified: 2022-07

Data Sharing

• IPD Sharing: Will not share

Locations

FR (1)