Abstract: APD-based PET modules are provided for use in combined PET/MR imaging. Each module includes a number of independent, optically isolated detectors. Each detector includes an array of scintillator (e.g. LSO) crystals read out by an array of APDs. The modules are positioned in the tunnel of a MR scanner. Simultaneous, artifact-free images can be acquired with the APD-based PET and MR system resulting in a high-resolution and cost-effective integrated PET/MR system.

Abstract: In a magnetic resonance (MR) system and method for determining an MR system frequency for a region to be examined that has multiple materials therein, a first frequency spectrum is acquired by the execution of a first RF excitation sequence. A second frequency spectrum for the region is acquired by radiation of an RF inversion pulse and execution of a second RF excitation sequence, at the point in time at which the relaxation curve of one of the materials has a zero-crossing. Subsequently, echo signals excited by the second RF excitation sequence are read out, from which a frequency spectrum is determined. The first frequency spectrum and the second frequency spectrum are compared. On the basis of the comparison, maxima of the first frequency spectrum are allocated to different materials. The system frequency is determined on the basis of the allocation of the maxima.

Abstract: APD-based PET modules are provided for use in combined PET/MR imaging. Each module includes a number of independent, optically isolated detectors. Each detector includes an array of scintillator (e.g. LSO) crystals read out by an array of APDs. The modules are positioned in the tunnel of a MR scanner. Simultaneous, artifact-free images can be acquired with the APD-based PET and MR system resulting in a high-resolution and cost-effective integrated PET/MR system.

Abstract: APD-based PET modules are provided for use in combined PET/MR imaging. Each module includes a number of independent, optically isolated detectors. Each detector includes an array of scintillator (e.g. LSO) crystals read out by an array of APDs. The modules are positioned in the tunnel of a MR scanner. Simultaneous, artifact-free images can be acquired with the APD-based PET and MR system resulting in a high-resolution and cost-effective integrated PET/MR system.

Abstract: A superconducting, actively shielded magnet has a first and second superconducting coil modules that generate a homogeneous magnetic field in a first direction in an operating volume of the magnet and that reduces the scatter magnetic field in an environment of the magnet. A third superconducting coil module is arranged in proximity to the first and second coil modules. The third coil module is fashioned to generate a compensation gradient field given occurrence of an interference gradient field in the environment so that the effect of the interference gradient field in the operating volume is reduced.

Abstract: The invention relates to a hearing protector for use in magnetic resonance systems. The hearing protector comprises a pad that is to be inserted in the ear and is provided on an adapter. A sound generating device is provided on or in the adapter or a sound transmitting device leads into same.

Abstract: A superconducting, actively shielded magnet has a first and second superconducting coil modules that generate a homogeneous magnetic field in a first direction in an operating volume of the magnet and that reduces the scatter magnetic field in an environment of the magnet. A third superconducting coil module is arranged in proximity to the first and second coil modules. The third coil module is fashioned to generate a compensation gradient field given occurrence of an interference gradient field in the environment so that the effect of the interference gradient field in the operating volume is reduced.

Abstract: A nuclear magnetic resonance tomograph or an imaging magnetic resonance apparatus (1) has a magnet (3) which is isolated in terms of vibration from a surrounding structure, in particular a building floor (15), by an isolation system (17). The isolation system (17) has an actively controlled isolation module (23) which is preferably designed to damp non-acoustic vibrations, in particular vibrations with a frequency of less than 50 Hz. According to a preferred embodiment, moreover, a passive isolation module (21) with a vibration-damping material (D) is present. A particularly high degree of isolation of the magnet (3) from the surrounding structure can be achieved with the aid of the isolation system (17).

Abstract: A nuclear magnetic resonance tomograph or an imaging magnetic resonance apparatus (1) has a magnet (3) which is isolated in terms of vibration from a surrounding structure, in particular a building floor (15), by means of an isolation system (17). The isolation system (17) has an actively controlled isolation module (23) which is preferably designed to damp non-acoustic vibrations, in particular vibrations with a frequency of less than 50 Hz. According to a preferred embodiment, moreover, a passive isolation module (21) with a vibration-damping material (D) is present. A particularly high degree of isolation of the magnet (3) from the surrounding structure can be achieved with the aid of the isolation system (17).

Abstract: In an image acquisition method in which there is a sensitivity characteristic over the image space that is non-uniform but that changes only slowly, this characteristic is determined according to the steps of, in the original image, intensity changes are limited to a predetermined maximum value, a low-pass filtering is applied to the auxiliary image acquired in this way, and the sensitivity characteristic of the image acquisition method over the image space is acquired from the low-pass-filtered auxiliary image.

Abstract: Two MR magnetic field probes arranged in a centrally symmetrical fashion in relation to the magnetic field center, are attached in the examination area of the magnet. The output signals of the two MR magnetic field probes are supplied to a multiplying RF mixer, and a sum frequency signal is obtained from the output signal of the RF mixer, and the actual value of the basic field is determined from the frequency of this output signal.