Abstract: A switchable gradient coil system is composed of saddle coils that can be operated respectively as primary coils or auxiliary coils. The auxiliary coils for one gradient axis, which exhibit a reduced subtended angle compared to the primary coils, are arranged in the gaps between coils that are arranged diametrically opposite each other in a radial plane for the other gradient axis.

Abstract: A nuclear magnetic resonance tomography apparatus has a magnet assembly with a first surface and a gradient coil assembly with a second surface, with an annular gap between these surfaces. A noise-reduction arrangement for damping the oscillations of the gradient coil assembly and/or for stiffening the gradient coil assembly is disposed in this gap in contact with the first and second surfaces. The noise-reducing arrangement can be composed of one or more components, and has contact surfaces, formed by one or more components, respectively in substantially surface-wide contact with the first and second surfaces of the tomography apparatus.

Abstract: An actively shielded transverse gradient coil arrangement contains a primary coil and a secondary coil that are arranged at a radial spacing from one another. Turns of the primary coil and the secondary coil disposed farther from the center of the examination volume in an axial direction of the gradient coil arrangement have a smaller radial spacing from one another than do turns lying close to the center. The parasitic flux density can thus be minimized. This is particularly important in EPI sequences for avoiding physiological stimulations in the examination subject.