Related Experiment Video
Updated: Oct 30, 2025
08:38
Testing of all Six Semicircular Canals with Video Head Impulse Test Systems
Published on: April 18, 2019
31.6K
Vestibular Function in Pendred Syndrome: Intact High Frequency VOR and Saccular Hypersensitivity
Niels Cramer West1, Alexander Christian Ryberg1, Per Cayé-Thomasen1,2
1Department of Otorhinolaryngology Head and Neck Surgery and Audiology, Rigshospitalet, University Hospital of Copenhagen.
Summary
Vestibular function in Pendred Syndrome (PS) patients is largely normal, despite anatomical abnormalities. Saccular function shows increased sensitivity, potentially due to the large vestibular aqueduct.
Area of Science:
- Otolaryngology
- Neuroscience
- Genetics
Background:
- Pendred Syndrome (PS) is a genetic disorder characterized by inner ear malformations, leading to hearing loss and vestibular dysfunction.
- Despite known anatomical abnormalities, objective vestibular function in PS patients remains understudied.
- Dizziness is common in PS, but its correlation with objective vestibular test results is not well-established.
Purpose of the Study:
- To objectively assess vestibular function in patients with Pendred Syndrome.
- To evaluate the vestibulo-ocular reflex (VOR) using the video head impulse test (VHIT).
- To assess saccular function using cervical vestibular evoked myogenic potential (cVEMP) testing.
Main Methods:
- Retrospective study of 26 Pendred Syndrome patients (52 ears) with severe-to-profound hearing loss.
- Video Head Impulse Test (VHIT) measured VOR gain and refixation saccades.
- Cervical Vestibular Evoked Myogenic Potential (cVEMP) assessed stimulus thresholds and amplitudes.
Main Results:
- 8% of ears showed pathological VHIT outcomes (low gain or saccades); no complete VOR loss was observed.
- cVEMP responses were present in 76% of ears; absence was linked to VHIT saccades and older age.
- cVEMP amplitude positively correlated with VHIT gain, suggesting a relationship between saccular and VOR function.
Conclusions:
- Vestibulo-ocular reflex (VOR) function, assessed by VHIT, is generally preserved in Pendred Syndrome patients.
- Saccular function, evaluated by cVEMP, appears abnormally sensitive in PS, indicated by low thresholds and high amplitudes.
- These findings support the 'third window' hypothesis in PS, related to the enlarged vestibular aqueduct impacting vestibular function.
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