Magnetic resonance imaging of endolymphatic space in patients with sensorineural hearing loss: comparison between fluctuating and idiopathic sudden sensorineural hearing loss

Abstract

Background: Recently, 3-Tesla magnetic resonance imaging (MRI) after an intravenous gadolinium injection has been used to describe the endolymphatic space (ELS).

Objectives: This study described the histopathological differences between idiopathic sudden sensorineural hearing loss (ISSNHL) and fluctuating sensorineural hearing loss (FSNHL) by examining the ELS. Additionally, the relationship between the affected cochlear and vestibular ELS/total fluid space (TFS) volume ratio and the duration from the onset to MRI in patients with FSNHL were evaluated.

Material and methods: This study included 205 individuals without vertigo: 47 controls, 94 with ISSNHL, and 64 with FSNHL. The TFS and ELS volumes were measured and the ELS/TFS volume ratios (%) were evaluated.

Results: The cochlear and vestibular ELS/TFS volume ratios of the affected ear in patients with FSNHL were significantly higher than that in those with ISSNHL. There was no correlation between the duration from FSNHL onset to the MRI scan in the affected cochlea and vestibule.

Conclusion and significance: There were differences in the form of hearing fluctuation and the extended ELS volume between ISSNHL and FSNHL. ISSNHL cases with severe ELS extension were likely to change to FSNHL.

Chinese abstract

背景：最近, 静脉注射钆后的3-Tesla磁共振成像（MRI）被用来描述内淋巴间隙（ELS）。

目的：研究特发性突发性感音神经性耳聋（ISSNHL）与波动性感音神经性耳聋（FSNHL）的组织病理学差异。此外, 还评估了FSNHL患者受影响的耳蜗和前庭ELS/总液体空间（TFS）容积比与从发病至进行MRI这段时间之间的关系。

材料与方法：本研究包括205名无眩晕的患者：47名对照组, 94名患ISSNHL, 64名患FSNHL。测量TFS和ELS体积, 并评估ELS/TFS体积比。

结果：FSNHL患者的耳蜗和前庭ELS/TFS容积比明显高于ISSNHL患者。患病耳蜗和前庭之间的从FSNHL发病到MRI扫描这段时长没有相关性。

结论与意义：ISSNHL与FSNHL在听力波动形式及扩展ELS体积方面存在差异。严重ELS扩展的ISSNHL患者有可能会转变为FSNHL。

Keywords:

• Cochlear type of Meniere’s disease
• endolymphatic space
• fluctuating sensorineural hearing loss
• idiopathic sudden sensorineural hearing loss
• magnetic resonance imaging
• prognosis
• volumetric measurement

Acknowledgements

The authors thank Prof. Kimihiro Kichikawa, Dr. Toshiteru Miyasaka (Department of Radiology, Nara Medical University, Nara, Japan), Prof. Shinji Naganawa, Associate Prof. Toshiaki Taoka (Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan). The authors also thank Dr. Hitoshi Yoshimura, Dr. Masahiko Sakamoto, other collaborators (Department of Radiology, Kouseikai Takai Hospital), and Mrs. Yuka Katsube (Inui ENT Clinic) for data aggregation. The authors thank Editage (www.editage.jp) for the English language editing.

Disclosure statement

No potential conflict of interest was reported by the author(s).