Inertial Enhancement to Mechanical Isolation of MR Gradient Coils
Publication Date: 2003-Apr-17
The IP.com Prior Art Database
Magnetic Resonance Imagers employ electrically excited coils to impose time varying magnetic fields on the larger, steady primary field provided by the main magnet. Since the imposed currents exist within a magnetic field, they produce corresponding forces on the conductors, which result in dynamic motions that propagate throughout the scanner. Repetitive pulses impart vibrational energy within the audio frequency range, resulting in pronounced acoustic noise. Those vibrations also transmit and propagate throughout the building site where they can emerge as noise sources in other rooms. In the MR suite, acoustic noise causes discomfort to the patient and operator and interferes with communication. Beyond the MR suite, acoustic noise can also interfere with clinical procedures, such as listening for irregularities in a patient's heart. This invention adds significant inertia to the coil support so that its motion is reduced, with respect to the gradient coil, without increasing the rigid body motion of the coil. This will reduce the acoustic emissions from the enclosure as well as structure-borne transmission through the cryostat into the floor and then into the site building structure.