Audiological Characteristics of Vestibular Schwannoma Patients With Normal Pure-Tone Audiometry

Weixun Zhang; Jianan Shi; Yanbo Yin; Mengye Ma; Jihan Lyu; Juanmei Yang; Weidong Zhao; Yasheng Yuan

doi:10.1002/ohn.783

Audiological Characteristics of Vestibular Schwannoma Patients With Normal Pure-Tone Audiometry

Otolaryngol Head Neck Surg. 2024 Apr 26. doi: 10.1002/ohn.783. Online ahead of print.

Authors

Weixun Zhang^{1

2

3}, Jianan Shi⁴, Yanbo Yin^{1

2

3}, Mengye Ma^{1

2

3}, Jihan Lyu^{1

2

3}, Juanmei Yang^{1

2

3}, Weidong Zhao^{1

2

3}, Yasheng Yuan^{1

2

3}

Affiliations

¹ Department of Otorhinolaryngology, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai, China.
² Research Institute of Otolaryngology, Fudan University, Shanghai, China.
³ Lateral Skull Base Diagnosis and Treatment Center, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai, China.
⁴ Fudan University, Shanghai, China.

PMID: 38667629
DOI: 10.1002/ohn.783

Abstract

Objective: To investigate the audiological characteristics of vestibular schwannoma (VS) patients with normal pure-tone audiometry (PTA) results.

Study design: A retrospective study.

Setting: Forty-two VS patients with normal PTA results from October 2016 to October 2022 were included.

Methods: Normal PTA was defined when the hearing threshold is ≤25 dB hearing loss (HL) in each test frequency and the PTA is ≤25 dB HL. Results of multiple audiological tests such as the auditory brainstem response (ABR), distortion product otoacoustic emission (DPOAE), multiple auditory steady-state responses threshold (ASSR), and speech discrimination score were retrospectively reviewed. Demographic data of these patients were also been collected.

Results: According to our results, the ABR and average ASSR threshold of the affected side were statistically significantly higher in VS patients with normal PTA. ABR waveforms on the affected side also showed more abnormalities. The DPOAE pass rates of the affected side were lower than the unaffected side while the amplitude and signal-to-noise ratio rate was also lower. In addition, we used magnetic resonance imaging 3-dimensional reconstruction images to measure the volume of tumors in these patients. We also found that higher ABR threshold means lager tumor size in patients with normal PTA.

Conclusion: VS patients with normal PTA result cannot be assumed to have no impairment of hearing function. ABR, DPOAE, and ASSR results showed the characteristic changes in the affect ear. ABR threshold has the highest sensitivity for hearing abnormalities and is strong relative with tumor size in patients with normal PTA.

Keywords: auditory brainstem response; pure‐tone audiometry; tumor size; vestibular schwannoma.