Meeting Banner
Abstract #2518

Brain MR Elastography Using Optimized Mechanical Vibration of the Patient Table

Mikio Suga1, 2, Takayuki Obata2, Hajime Ikeda1, Shinya Ozawa1, Atsuhisa Koyama1, Tetsuya Wakayama3, Riwa Kishimoto2

1Chiba University, Chiba, Japan; 2National Institute of Radiological Sciences, Chiba, Japan; 3GE Healthcare, Tokyo, Japan

According to a previous study, the vibrations of the patient table that result from the impulse of an imaging gradient lobe could be used as a mechanical driving mechanism for MR elastography (MRE). However, the vibration frequency must be optimized so that high spatial resolution and accurate storage-modulus maps (elastogram) can be obtained. In this study, we add sinusoidally switching gradients before a conventional MRE pulse sequence and measure the amplitude of the patient table as it vibrates during acquisition. To evaluate the elasticity of the brain using the specific mechanical resonance frequencies of the patient table, heterogeneous phantom and in-vivo brain experiments are performed. The results suggest that the proposed method will enable accurate measurement of the brain elasticity.

Abstract PDF Poster PDF

Keywords

accuracy accurate acquisition adapted advantage alternatively amplitude amplitudes anal application applied array axis background brain channel clinical coil conducted constructed contrast creates cycles cylinder cylindrical deeper diameter directly drivers driving duration dynamic easily eight elasticity embedded enable estimation evaluate excitations external field five frequencies frequency function gels generate generated good gradient gradients gray head healthy heterogeneous human impulse in vivo inclusions inducing inside institute insufficient japan larger laser lobe local long male maps materials matrix measure measured measuring mechanical mechanism moduli modulus movement must national noninvasive offsets optimized patient peaks penetrate phantom proposed protocol pulse quantitative radiological reliable repetition resolution respectively scanning science sciences shear shot simulating sinusoidally slice slices spatial spin storage studies subject sufficient suggest suggested switching table tissue unit various vibrates vibration vibrations view wave waves white whole year