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.