| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an MRI apparatus 1 reduced in noise without its enlargement.SOLUTION: A magnetic resonance imaging apparatus comprises: a magnetostatic field magnet 2 that generates a magnetostatic field in an image capturing space 8; a gradient magnetic field coil 4 that generates a gradient magnetic field in the image capturing space 8; an exterior cover 5 that is arranged so as to cover the magnetostatic field magnet 2 and the gradient magnetic field coil 4; and a gas bag 6 that is arranged on the side of the image capturing space 8 of the gradient magnetic field coil 4 within the exterior cover 5 and contains gas 6c having different acoustic impedance from surrounding air. The gas bag 6 deforms according to an amount of sealed gas 6c. Pressure in the gas bag 6 is approximately equal to that of the surrounding air. The acoustic impedance of the sealed gas 6c in the gas bag 6 is smaller than that of the surrounding air of the gas bag 6. The gas bag 6 is distant from the gradient magnetic field coil 4 and the exterior cover 5.</p> |
