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Updated: May 14, 2026
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Electrically Evoked Stapedius Reflex Measurements in Cochlear Implantation and Its Application in the Postoperative Fitting Process
Published on: June 21, 2024
Stapedial synkinesis causing change in hearing threshold with facial motion
Michal A Brichacek1, Michael G Brandt, John P Carey
1Department of Otolaryngology-Head and Neck Surgery, Division of Facial Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Summary
Facial nerve injury can cause synkinesis, rarely affecting hearing. This case details stapedial synkinesis causing a 10 dB hearing decrease with lip puckering, highlighting the need for audiology evaluation in facial movement disorders.
Area of Science:
- Neurology
- Otolaryngology
- Audiology
Background:
- Synkinetic facial movement is common after facial nerve regeneration.
- Stapedial muscle involvement in synkinesis can cause auditory symptoms like ear fullness.
- Significant changes in hearing threshold due to synkinesis are exceedingly rare.
Observation:
- A patient developed stapedial synkinesis after acoustic neuroma resection.
- Facial nerve paralysis improved, but synkinesis caused lip puckering with eye closure.
- Lip puckering led to a 10 dB decrease in pure-tone average (PTA) hearing in the affected ear.
Findings:
- The observed hearing reduction aligns with the stapedial reflex's 15-dB attenuation.
- Facial nerve function and hearing symptoms gradually improved over several months.
- No intervention was required due to the transient and improving nature of the symptoms.
Implications:
- This case underscores the rare but potential link between facial synkinesis and hearing threshold changes.
- Audiometric evaluation during facial muscle contraction may be beneficial for diagnosing stapedial synkinesis.
- Surgical sectioning of the stapedial muscle could be a future treatment option for persistent cases.
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