Magnetic resonance volumetric measurement of endolymphatic space in patients without vertiginous or cochlear symptoms

Abstract

Conclusion: Magnetic resonance volumetric measurement of inner ear endolymphatic space (ELS) was performed in patients without vertiginous or cochlear symptoms. The existence of the ELS in patients with chronic rhinosinusitis (CRS) was shown. The ELS in the cochlea and vestibule was classified into four categories. These findings could be useful as a standard reference for further research.

Objectives: To identify normal values of the ELS in the cochlea and vestibule.

Methods: Twenty-four patients with CRS were enrolled. Inner ear fluid space images and positive perilymph/positive endolymph images were acquired using a 3.0-tesla unit. Three-dimensional (3-D) images were constructed semi-automatically using both anatomical and tissue information by fusing the 3-D images of the inner ear fluid space and the ELS.

Results: Among all patients, the mean ELS/the total fluid space (TFS) ratio in the cochlea was 8.8% and that in the vestibule was 16.2%. The ELS in the cochlea and vestibule was classified into four categories. Age-related differences were found in the TFS, ELS, and ELS/TFS ratio in the inner ear and the ELS and ELS/TFS ratio in the vestibule.

Keywords:

• Age-related difference
• endolymphatic space
• fusing image
• normal value
• quantitative measurement

Acknowledgments

We thank Professor Kimihiro Kichikawa, Dr Toshiteru Miyasaka, Mr Yuya Yamatani, and Mr Kozo Shimizu (Department of Radiology, Nara Medical University, Nara, Japan) as well as Professor Shinji Naganawa and Associate Professor Toshiaki Taoka (Department of Radiology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan).

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.