Three Dimensional and High Resolution Magnetic Resonance Imaging of the Inner Ear

Normal Ears and Anomaly Scanned with 3D-CISS Sequence

Abstract

The MRI system used in this study was a new scanning sequence, 3D-CISS (Three dimensionalconstructive interference in steady state) with 1.5 Tesla. Ten normal ears and one ear with Mondini type anomaly were scanned and reconstructed.
In Imagings of normal inner ears, the cochlea has three spiral layers; basal, middle and apical turns. Each turn was separated into three parts; the scala vestibuli, osseous spiral lamina and scala tympani.
Three semicircular ducts, utricle and saccule were also reconstructed in one frame.
In the inner ear of Mondini anomaly, 3D MRI showed cochlear aplasia, hypoplasia of semicircular ducts and widely dilated vestibule. The imaging was identical with findings of “common cavity”. The anomaly was easily recognized in 3D MRI more than in 2D imagings.
The detailed and cubic imagings of the Mondini anomaly in 3D MRI could not be observed with conventional 2D MRI. 3D MRI is not invasive method and can scan a target very quickly.