Analysis of the MRI driving sound in case of gradient magnet field controlled by the original sequence

MRI equipment is important for medical diagnosis. The driving sound is loud, and the noise levels exceed 100dB. It is unpleasant for patients. The operation of the gradient magnetic field for imaging generates the loud sound. The gradient magnetic field of the equipment of high magnetic field is generated with the coil of three orthogonal axles. Many researches only show the sound driven by the synthesized the gradient magnetic field of three axles. In this paper, the characteristic of the sound by the operation of the gradient magnetic field only of one axle by the self-made sequence is shown. The measurement equipment is Signa Horizon LX 1.5T of GE Yokogawa medical systems. This equipment has the performance of the static magnet field of 1.5 teslas, gradient magnetic field of 22mT/m, and slew rate of 77T/m/ms. In this measurement, the gradient magnetic field is controlled without the radio frequency pulse that generates the noise signal. The sound is measured near the center in the bore of the equipment. In this measurement, the strength of the gradient magnetic field was changed, and the linearity between the sound pressures was clarified.