Audio-vestibular evaluation in patients with essential tremor

Area of Science:

• Neuroscience
• Audiology
• Ophthalmology

Background:

• Essential tremor (ET) is a neurological disorder primarily affecting motor control.
• Audio-vestibular function in ET patients is not well understood.
• Hearing impairment can significantly impact quality of life.

Purpose of the Study:

• To investigate audio-vestibular function in patients diagnosed with essential tremor.
• To compare hearing and vestibular test results between ET patients and healthy controls.
• To explore potential correlations between ET severity, duration, and audio-vestibular parameters.

Main Methods:

• Included 23 ET patients and 21 age/gender-matched healthy controls.
• Utilized pure tone audiometry, tympanometry, transient-evoked otoacoustic emissions (TEOAEs), and auditory brainstem response (ABR).
• Assessed vestibular function using bithermal caloric testing.

Main Results:

• Significant differences in pure tone thresholds at 250 and 500 Hz between ET patients and controls.
• No significant differences in higher frequencies (1-6 kHz) or ABR latencies.
• Otoacoustic emission responses were significantly different in ET patients compared to controls.
• No correlation found between tremor severity/duration and audiometric scores.

Conclusions:

• Essential tremor is associated with cochlear dysfunction, indicated by low-frequency hearing loss and abnormal TEOAEs.
• Hearing loss in ET appears to stem from cochlear, rather than retrocochlear, pathology.
• Further research is warranted to elucidate the mechanisms of audio-vestibular involvement in ET.