Abstract: In a method for imaging a metabolic event of an organism, a substance (involved in the metabolism) to be imaged is marked with a substance that exhibits a high T1 and is polarized. The marked and polarized substance involved in the metabolism is administered to the organism. An image of a region of the organism is generated with a magnetic resonance device, this image showing the distribution of the polarized substance in the region.

Abstract: In a magnetic resonance apparatus and method to acquire a diffusion-weighted image in diffusion-weighted MRT imaging, a non-diffusion-weighted data set and a diffusion-weighted data set are measured and stored by means of a DESS sequence (Double Echo Steady State Sequence), with two readout gradients being switched successively for the non-diffusion-weighted data set, and a bipolar diffusion gradient pulse sequence being switched between two readout gradients for the diffusion-weighted data set. A diffusion-weighted MRT image is calculated is calculated based on the non-diffusion-weighted data set and the diffusion-weighted data set, as well as on the basis of a value characterizing the diffusion-weighted measurement.

Abstract: A method is for producing a map from raw magnetic resonance data from a magnetic resonance tomography unit or a spectrum from raw magnetic resonance data from a magnetic resonance spectroscopy unit. The method involves the raw data being filtered, preferably using a high pass filter and using a low pass filter. Next, the two absolute values of the filtered, Fourier transformed raw magnetic resonance data are used to produce the map or the spectrum by a weighted combination. The method is distinguished in that the signal to noise ratio can be improved together with an increase in the edge sharpness.

Abstract: In a head-fixing device for a medical imaging examination device, an acoustic signal emitter is integrated into the head-fixing device. A fixing cushion is shaped such that when fixing the head it forms a chamber enclosing the ear. In this chamber, sound is transmitted pneumatically via an air canal.

Abstract: In a magnetic resonance imaging method and apparatus, a double echo sequence having a gradient echo and a spin echo is implemented with a flow compensation for the gradient echo in at least one direction.

Abstract: In a magnetic resonance tomography apparatus and method, whereby an interactive contrast optimization is implemented by defining a multi-contrast sequence for exciting nuclear spins in a slice of a subject to be measured, defining parameters characteristic of the sequence, measuring a number of contrast versions of the slice in the form of raw data with the previously defined sequence, processing the raw data of the slice, and thereby generating a number of images of the slice that differ in contrast from one another and generating an image with improved contrast on the basis of an interactive real-time contrast variation of the images acquired by the multi-contrast sequence, via a user interface.

Abstract: In a method and apparatus for generating an image from magnetic resonance signals, two image matrices generated from magnetic resonance signals are added to or subtracted from one another pixel-by-pixel, to generate a further image therefrom. The magnitude added or subtracted for each picture element is formed by multiplication of a magnitude value of the second image matrix by a weighting factor. The weighting factor is dependent on the magnitude value of the second image matrix such that it is higher given a high magnitude value than for a low magnitude value. The magnitude noise is decreased compared to a linear addition or subtraction, and uncontrolled signal reductions are avoided. An exponent in the power of the magnitude value of the second image matrix a signal-dependent weighting factor can be set at an input device.

Abstract: In a magnetic resonance tomography apparatus, and a pulse sequence for operating the apparatus, a radio frequency pulse, having a flip angle of &agr;/2 is emitted into a subject in a first pulse sequence section, by second and third pulse sequence sections in which a sequence of radio frequency pulses is emitted, each having a flip angle &agr; and a repetition time which is lower than the T1 and T2 relaxation times of the subject, the subject eventually reaching a steady state equilibrium condition after which the third pulse sequence section begins. In the third pulse sequence section, magnetic signals are read out from the subject with a phase coding, the phase coding being reset before the next radio frequency pulse in the sequence.

Abstract: In a method for the operation of a nuclear magnetic resonance tomography apparatus for separating water and fat signals a true FISP sequence is implemented with a repetition time TR, so that fat-bonded protons experience a phase rotation of approximately n·180° due to the effect of the chemical shift relative to water-bonded protons, with n being an odd number. Dependent on the further configuration of the sequence, either fat-bonded protons or water-bonded protons exhibit only a slight magnetization in the steady state condition, and thus contribute only little to the measured signal.

Abstract: In a gradient echo sequence for a magnetic resonance imaging apparatus, at least two gradient echo signals are acquired between two excitation pulses due to the influence of a bipolar readout gradient. The respective echo times of the gradient echo signals are selected such that signals from atomic nuclei of different chemical bonding add in the one instance but subtract in another instance. Two images with different diagnostic content can be acquired from these two types of gradient echo signals.

Abstract: In a nuclear magnetic resonance tomography apparatus and a method in the form of a pulse sequence for operating the apparatus, after an excitation of spins in a subject, two groups of nuclear magnetic resonance signals are obtained in two time intervals at different chronological spacings from the excitation time. An image is obtained on the basis of the signal differences of nuclear magnetic resonance signals of the first and second groups with corresponding locus-encoding. Signal contributions from tissues with longer T2 relaxation time can thereby be screened out.

Abstract: In a steady-state pulse sequence having a repetition time and a flip angle .alpha. with alternating polarity for operating a magnetic resonance imaging apparatus, the excursion of the magnetization in the steady-state condition moves between a first value +.alpha./2 and a second value -.alpha./2. Before the beginning of the pulse sequence, a radiofrequency pulse having a flip angle .alpha./2 is emitted before the first excitation pulse. The steady-state condition is thus reached earlier and a spin preparation can be implemented which is still effective when imaging data are acquired.

Abstract: Nuclear spins are excited in an examination subject by a sequence of radio-frequency pulses that are emitted in under the influence of slice selection gradients, with n different slices of the examination subject being excited. Due to read-out gradients, n gradient echoes respectively allocated to a slice are generated such that each gradient echo allocated to a radio-frequency pulse comes to lie between two successive radio-frequency pulses. Further slices can thus be excited within the echo time of a gradient echo of a specific slice. A T.sub.2.sup.* contrast image can thus be obtained with a significantly shorter examination time than was heretofore achievable.

Abstract: A sequence of chronologically non-equidistant radio frequency excitation pulses and a first gradient are activated during an excitation phase. The existing spin magnetization is divided into sub-groups by each excitation pulse that follows the first excitation pulse. A chronologically graduated focusing of the individual sub-groups ensues during the read-out phase under a further gradient. A number of nuclear magnetic resonance signals can thereby be acquired following a single excitation phase, so that a short image pick-up time becomes possible, without the necessity of a fast switching of the gradients. Further, pure spin echoes can be acquired, which are insensitive to local field inhomogeneities in comparison to gradient echoes.

Abstract: In magnetic resonance spectroscopy and imaging, it is usually necessary to obtain spectra only from desired, localized regions of an examination subject. This is accomplished by subjecting the examination subject to a selective radio-frequency (RF) pulse. A method for optimizing the pulse shape of such a radio-frequency pulse includes the steps of exciting a spin system with a frequency-selective radio-frequency pulse, reading out the resulting echo signal, cutting off high-frequency signal components of the echo signal using a filter, and employing the filtered echo signal as the optimized radio-frequency pulse shape.

Abstract: A pulse sequence for operating a magnetic resonance imaging apparatus for fast calculation of images of the fat and water distribution in an examination subject includes the steps of charging the examination subject with a first radio-frequency pulse which is selective with respect to a first spectral component and charging the examination subject with a second radio-frequency pulse which is selective with respect to a second spectral component. A dephasing gradient is activated between the two radio frequency pulses. The spin system is thus phase coded in two directions. A signal with respect to the second spectral component is read out under a first read-out gradient and a signal with respect to the first spectral component is read out under a second read-out gradient. Images of the fat and water distribution in the examination subject can thus be acquired with one measuring sequence.

Abstract: A method for obtaining an image in a magnetic resonance imaging apparatus uses a steady state pulse sequence which is based on a combination of a FISP pulse sequence and a PSIF pulse sequence. To signals are obtained by executing a sequence of steps once with alternating phase relation of the RF pulses, which excite the nuclear spins, and once with non-altering phase relation. By subtracting these signals, a pure PSIF signal is obtained, and the steady state is not disturbed by the moving spins. The flux phase is also compensated by the additional introduction of gradient motion refocusing (GMR) pulses, so that images of pulsating examination subjects, such as cerebral spin fluid, can be obtained free of flux artifacts.

Abstract: A nuclear magnetic resonance tomography apparatus has coils for respectively generating fundamental and gradient magnetic fields in which an examination subject is disposed, and RF coil for displacing the nuclear spins of the examination subject from an equilibrium position, and direct galvanic connections to the examination subject for obtaining the nuclear magnetic resonance signals arising during relaxation of the excited nuclear spins. The examination subject thus becomes a part of the reception antenna or the feed line thereof, thus avoiding the use of an RF coil for acquiring such signals.