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RecruitingNCT04859335EQUI-GAMMAUpdated Aug 11, 2026

Evolution of Balance and Vestibular Function in Patients Treated With Gammaknife Radiosurgery for Vestibular Schwannoma

An interventional study of gammaknife radiosurgery in Vestibular Schwannoma, sponsored by University Hospital, Toulouse. Recruiting at 1 site in France. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-08-11.

Sponsored by University Hospital, Toulouse · Not applicable, Interventional, and Health services research

From the registry’s dates

  • Started May 2021; still recruiting 5 years 5 months later.
Phase
Not applicable
Study type
Interventional
Enrollment
50
Allocation
Not applicable
Ages
18 Years to 65 Years
Sex
All
01

Study summary

Vestibular schwannomas are benign lesions of the ponto-cerebellar angle that are potentially dangerous because of their growth in a cramped space and the compressive phenomena they can cause. Stereotactic Gammaknife radiosurgery is a treatment option that can be offered for evolutive schwannomas smaller than 2.5-3 cm in size. It allows tumor stabilisation in 85% of cases with less than 1% facial nerve damage risk.

There are controversial results regarding hearing preservation : percentages vary between 25 and 80% in the literature, depending on the criteria used and the post-treatment delay.

Few studies have investigated changes in vestibular function and the impact on balance of radiosurgery, and their results are variable.

These controversial results lead us to comprehensively assess the vestibular function and balance of these patients using a balance-specific quality of life questionnaire, in addition to objective overall vestibular assessments of vestibular function.

Read the detailed description

Vestibular schwannomas are benign lesions of the ponto-cerebellar angle that are potentially dangerous because of their growth in a cramped space and the compressive phenomena they can cause. Stereotactic Gammaknife radiosurgery is a treatment option that can be offered for evolutive schwannomas smaller than 2.5-3 cm in size. It allows tumor stabilisation in 85% of cases with less than 1% facial nerve damage risk.

There are controversial results regarding hearing preservation : percentages vary between 25 and 80% in the literature, depending on the criteria used and the post-treatment delay.

Few studies have investigated changes in vestibular function and the impact on balance of radiosurgery.Their results are heterogeneous, on one hand, indicating little worsening of symptoms, or even improvement in some studies. On the other hand, a 2017 study reported symptomatic worsening of caloric response deficits in 17.6% of cases. Vestibular function at high frequencies or for otolithic organs (utricle and saccule) has hardly ever been explored.

The largest cohort, reported in "gammaknife radiosurgery for vestibular schwannomas a quality of life evaluation" concerns 353 patients and shows that the overall quality of life of the patients treated is on average comparable to that of the general population but that the vertigo is more frequent in this population, with a more marked impact on the overall quality of life.

These controversial results lead us to comprehensively assess the vestibular function and balance of these patients using a balance-specific quality of life questionnaire, in addition to objective overall vestibular assessments of vestibular function.

Thus, the present study aims to assess the quality of balance of patients treated with Gammaknife radiosurgery for vestibular schwannoma at 1 year and 3 years after treatment.

02

Conditions studied

  • Vestibular Schwannoma

Keywords

  • Vestibular Schwannoma
  • Gammaknife radiosurgery
  • Dizziness
  • Balance
03

In context

Neuroma, Acoustic

100 studies on the registry are indexed under Neuroma, Acoustic; 28 are open to participants now.

This study's planned enrollment of 50 is above the median of 27 across 65 interventional studies indexed under Neuroma, Acoustic.

Browse Neuroma, Acoustic studies →

Lead sponsor

University Hospital, Toulouse is the lead sponsor of 807 studies on the registry; 209 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 65 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Vestibular schwannoma's Patients for whom an indication of gammaknife radiosurgery was determined in a dedicated multidisciplinary consultation meeting, having not received previous treatment for this schwannoma.
  • Patient affiliated to Social Security
  • No opposition to participation

Exclusion criteria

Exclusion Criteria:

  • History of prior treatment for the presented vestibular schwannoma (surgery, fractional radiotherapy)
  • History of otological or otoneurological pathology associated with schwannoma
  • Patient with type 2 neurofibromatosis
  • Patient under legal protection
  • Pregnant or breastfeeding women
05

Study design

Phase
Not applicable
Primary purpose
Health services research
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
50 participants (estimated)

Study arms

  • Other
    Schwannomas patients needing gammaknife radiosurgery

    Patients will undergo balance and hearing questionnaires before and after gammaknife radiosurgery. This is a before/after analysis needing only one arm: the "before" data will serve as control to the "after" data

    Radiation: gammaknife radiosurgery

Interventions

  • Radiationgammaknife radiosurgery

    Patients will undergo questionnaires before the gammaknife radiosurgery, then one year and three years after the intervention.

06

What researchers measure

Primary outcomes

  1. quality of the perceived balance, assessed by the French version of the Dizziness Handicap Inventory (DHI)

    Questionnaire including 25 items with a "yes/no/maybe" answer possibility

    Time frame: before gamma knife radiosurgery (Baseline)

  2. quality of the perceived balance, assessed by the French version of the Dizziness Handicap Inventory (DHI)

    Questionnaire including 25 items with a "yes/no/maybe" answer possibility

    Time frame: One year after gamma knife radiosurgery

  3. quality of the perceived balance, assessed by the French version of the Dizziness Handicap Inventory (DHI)

    Questionnaire including 25 items with a "yes/no/maybe" answer possibility

    Time frame: Three years after gamma knife radiosurgery

Secondary outcomes

  1. Evolution of hearing

    Evaluate the evolution of hearing using data obtained during tonal audiometry (frequency by frequency between 250 Hz and 8 kHz, average hearing loss calculated on the frequencies 0.5, 1, 2, and 4 kHz)

    Time frame: before gamma knife radiosurgery (Baseline)

  2. Evolution of hearing

    Evaluate the evolution of hearing using data obtained during tonal audiometry (frequency by frequency between 250 Hz and 8 kHz, average hearing loss calculated on the frequencies 0.5, 1, 2, and 4 kHz)

    Time frame: One year after gamma knife radiosurgery

  3. Evolution of hearing

    Evaluate the evolution of hearing using data obtained during tonal audiometry (frequency by frequency between 250 Hz and 8 kHz, average hearing loss calculated on the frequencies 0.5, 1, 2, and 4 kHz)

    Time frame: Three years after gamma knife radiosurgery

07

Study locations

1 of 1 sites recruiting
08

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Aug 11, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT04859335
Responsible party
Sponsor
First posted
Apr 26, 2021
Start date
May 21, 2021
Primary completion
Dec 1, 2028 (estimated)
Completion
Dec 1, 2028 (estimated)
Last update
Aug 11, 2026

Study contacts

Mathieu MARX, MD Phd
Contact
marx.m@chu-toulouse.fr
(+33)5 61 77 77 04
Mathieu MARX, MD PhD
principal investigator · University Hospital, Toulouse

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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