Abstract: In magnetic resonance imaging apparatus k-space data received from r.f. excitation pulses applied at successive phase-encode gradients and read-out while other gradients are applied is collected for individual coils of an array of r.f. receive coils. A processor 22 uses the lines of data received by each r.f. receive coil at each phase-encode gradient together with reference spatial sensitivity profiles of each coil in a phase-encode direction represented in terms of spatial harmonics of a fundamental frequency one cycle of which corresponds with a desired field of view, to generate a set of phase-encode lines. These lines are converted to image space in Fourier Transform processor 25 to produce an image for display on monitor 26.

Abstract: A fluid movement system for moving a sample fluid is preferably included in a cartridge to be inserted into a reading device. The fluid movement system includes a pressure variation means for moving the sample fluid under the influence of a pressure variation applied to the fluid movement system, and a timing means for controlling the timing for releasing a pressure in the pressure variation means.

Abstract: A coil system (210) for an apparatus operating in conformity with the spin resonance or magnetic resonance (MR) method encloses an examination space (217) which extends along an axis (218) and is intended to receive a patient (215). It includes an inner RF coil (219), an inner sub-coil (213?) which externally encloses the RF coil (219) and projects beyond the RF coil (219) in the axial direction at both sides, and an active shield (212) which externally encloses the inner sub-coil (213?) and constitutes a gradient coil arrangement in conjunction with the inner sub-coil (213?). For specified gradients, the energy required for the gradient coil arrangement (213?, 212) in such a coil system is reduced in that the volume occupied by the inner sub-coil (213?) is extended in the axial direction by way of regions extending beyond the RF coil (219) in the direction of the axis (218).

Abstract: A CT-scanner having a gantry comprising a stator and a rotor, wherein an X-ray source and array of X-ray detectors are mounted to the rotor for determining absorption of X-rays along paths through the body of a patient imaged by the CT-scanner, the CT imager comprising: a processor that processes data comprised in signals generated by the X-ray detectors responsive to intensity of X-rays from the X-ray source incident on the detectors to generate an image of the patient; at least one spread spectrum transmitter that receives data comprised in the signals generated by the X-ray detectors and transmits signals encoded with the data in accordance with a spread spectrum coding; and at least one spread spectrum receiver that receives the encoded signals transmitted by the at least one spread spectrum transmitter and forwards the encoded data to the processor.

Abstract: The invention relates to a method of analyzing an object data set comprising points in a multi-dimensional space, in which dataset a tubular structure, such as blood vessels, occurs. The method comprises the following steps: a) choosing a screen position related to the tubular structure; b) determining the multi-dimensional co-ordinates of a starting position associated with said screen position; c) deriving a plane through said starting position having its normal directed to the tubular structure; d) determining a surface point of the tubular structure as a target position associated with the starting position; e) selecting a number of points forming part of the surface of the tubular structure in the vicinity of the target position; f) determining the surface point in the selection which is closest to the plane; and g) using the surface point determined in the step f) as a new starting position. This method allows accurate and reproducible selection of the starting position.

Abstract: An RF coil system for a magnetic resonance imaging apparatus whereby a substantially computer-aided and hence automatically optimized image quality in respect of signal-to-noise ratio and resolution can be achieved in dependence on the type and size of the object to be imaged, without time-consuming replacement or manual positioning of the RF coil system being necessary. To this end, the coil system (A) includes a plurality of single RF coils (Sx) which are essentially decoupled from one another and have a different size and/or different position, as well as a control device with a plurality of transmission units which are associated with a respective RF coil and whereby one or more RF coils can be selected and supplied with an RF pulse having an independently adjustable amplitude and/or phase and/or pulse shape. The invention also relates to a magnetic resonance imaging apparatus provided with such an RF coil system.

Abstract: A magnetic resonance imaging (MRI) apparatus (10) acquires a plurality of parametric images (60) with at least one varying imaging parameter. A parametric map (62) is constructed from the plurality of parametric images (60). At least one pilot parameter (64) is identified from at least the parametric map (62). The at least one identified pilot parameter (64) includes at least a volume of interest for a diagnostic image. A contrast agent (54) is administered to the patient (18). The identified volume of interest is imaged during influx of the administered contrast agent (54) into the identified volume of interest. The imaging uses the at least one identified pilot parameter (64).

Abstract: The invention relates to an arrangement for generating RF fields in the examination volume (100) of an MR apparatus. A plurality of resonator segments are arranged around the examination volume (100) within the gradient tube (103), said resonator segments being connected together so as to form a body coil. Each resonator segment is provided with a conductor element (104) which is constructed as a planar strip and extends parallel to the longitudinal axis of the main field magnet. The resonator segments are electromagnetically decoupled from one another by means of intermediate capacitances, so that a separate transmission channel (1 to 8) can be associated with each resonator segment, the RF feeding into the relevant resonator segment taking place via said channel.

Abstract: In apparatus for magnetic resonance imaging equipped for parallel imaging, in the sense that an array of receive coils can be used to regenerate data at phase-encode gradients interposed between those at which measurements were taken, the full set of data is collected, which is then split into two sets with a greater separation of phase-encode gradients (FIGS. 13 and 14). These sets are then each regenerated (FIGS. 15 and 16), enabling spurious data to be excised from the original data set by comparison of the two representations.

Abstract: A magnetic resonance imaging method which involves a pulse sequence for generating magnetic resonance signals and in which diffusion weighting is applied, for example, by way of a pair of gradient pulses which are separated by a 180° refocusing RF pulse. The magnetic resonance signals are generated as spin echo signals due to refocusing pulses. The refocusing pulses are flanked by compensation gradient pulses and the gradient strengths of the compensation gradient pulses are alternated according to a periodic pattern.

Abstract: The invention relates to a computed tomography apparatus in which measuring data of a patient is acquired along a helical trajectory by means of a conical radiation beam. The size of the detector window is then a factor of 3, 5, 7 . . . larger than the distance between neighboring turns of the helix. In order to select from among the acquired redundant data the data which is suitable for completely filling the Radon domain so as to achieve exact reconstruction, in accordance with the invention it is proposed to provide a cardiac motion signal detection device for the detection of a cardiac motion signal representing the cardiac motion and to arrange the reconstruction unit so as to select such measuring data from among the measuring data regionally redundantly filling the Radon domain that the Radon domain is completely and homogeneously filled with measuring data from cardiac motion phases with as little motion as possible.

Abstract: The invention relates to an MR apparatus that is provided with an open magnet system and a quadrature coil system that includes a resonator that is tuned by tuning capacitors on at least one of the two sides of the steady magnetic field, said resonator including two large-area electrical conductors that are situated at a distance from one another and are connected to one another in a number of connection points that are distributed along the circumference, and are also provided with at least two terminals that are distributed along the circumference in order to receive or generate RF magnetic fields that are mutually offset in phase. The invention also relates to a corresponding quadrature coil system.

Abstract: In a method of visualizing a three-dimensional volume image data set (1), a two-dimensional image (15) is formed by projecting volume image data on a projection plane in that for each pixel (16) there is determined an intensity value which corresponds to the maximum value or minimum value of the mean intensity along a projection path (17) through the imaged volume and associated with the relevant pixel. In order to determine the mean intensity, averaging is performed over a plurality of intensity values which neighbor one another along the projection path (17). In order to achieve effective noise suppression as well as adequate along image contrast , averaging is performed over at least partly overlapping interval (18 to 22) along the projection path (17). The method offer the advantage that the user can choose the width of the averaging interval as an additional free parameter, so that image contrast and background noise can be influenced independently.

Abstract: A medical imaging system for conducting an image-guided medical procedure on a subject and a method for performing the same is provided. The system includes a medical imaging apparatus, such as a CT scanner, magnetic resonance imaging system, or ultrasonic imaging system, etc., for obtaining volumetric images of the subject. Through intervention planning techniques, an interventional procedure on a subject using the volumetric images is determined. A mechanical arm assembly disposed in proximity to the medical imaging apparatus carries out the interventional procedure. The mechanical arm assembly includes a base support, a distal end, a plurality of arm segments, and a plurality of joints between the arm segments for carrying out the interventional procedure. An end-effector is disposed at the distal end of the mechanical arm assembly. The end-effector includes gripping means for selectively gripping and releasing a surgical instrument during the interventional procedure.

Abstract: At least one reference plane, but preferably three orthogonal reference planes (A, C, S) are defined in a magnetic resonance imaging method. A cut plane is chosen so as to extend at an angle to one (single oblique) (SO) or two (double oblique) (DO) of the reference planes. One side of the field of view within the cut plane remains parallel to one (of the) reference plane (planes). A cross-sectional magnetic resonance image along the cut plane is reconstructed from magnetic resonance signals.

Abstract: The invention relates to a mammography accessory for MR elastography which is capable of generating longitudinal oscillations which extend in the longitudinal direction in the mammae of a patient to be examined. The examination time can thus be reduced while at the same time realizing a rendition of the mammae in transverse slice images which is acceptable to examiners.

Abstract: A magnetic resonance imaging system comprises an excitation antennae system (13,16) including several antennae for emitting an RF-excitation field [B1(t)]. An activation control unit (ACU) is coupled to the excitation antennae system to activate the excitation antennae system. Individual antennae are activated to simultaneously emit separate RF-excitation constituents [Bn(t)]. The RF-excitation constituents have different activation distributions over k-space. and the time required for the RF-excitation is short even for complex spatial excitation patterns.

Abstract: A fluoroscopy intervention method to obtain an image of an object (11) together with radiopaque intervention means (30), the method using a rotating cone-beam X-ray source (8,9) and a corresponding two-dimensional X-ray detector (6) with the object (11) and the intervention means (30) positioned between the X-ray source (8) and the X-ray detector (6). Due to a cone-beam acquisition and a multi-slice reconstruction (9′) the intervention means (30) can have a substantial angulation with respect to the image slices (9′), providing the operator's hand (4) being outside the primary X-ray beam (9). This reduces the X-ray dose the operator. By providing additional lighting means (60), delineating the primary X-ray source at its periphery, the operator is supplied with an information about the spatial position of the X-ray radiation. The lighting means (60) can be further used to position an X-ray shield (65) of a surface of the patient to reduce the X-ray dose due to scattered radiation.

Abstract: An imaging method (150, 190) for imaging a subject (16) including fibrous or anisotropic structures (102) includes acquiring a three-dimensional apparent diffusion tensor map (162) of a region with some anisotropic structures (102). The apparent diffusion tensor at a voxel is processed (164) to obtain eigenvectors (e1, e2, e3) and eigenvalues (&lgr;1, &lgr;2, &lgr;3). A three-dimensional fiber representation (208) is extracted (198, 200) using the eigenvectors and eigenvalues. During the extracting (198, 200), voxels are locally interpolated (202) in at least a selected dimension in a vicinity of the fiber representation (208). The interpolating includes weighting the voxels by a parameter indicative of a local anisotropy. The interpolating results in a three-dimensional fiber representation (208) having a higher tracking accuracy and representation resolution than the acquired tensor map (162).

Abstract: A magnetic resonance imaging apparatus is provided. The magnetic resonance imaging apparatus includes a main magnet assembly for generating a main magnetic field in a main magnetic field direction in an examination region, a gradient coil assembly for generating magnetic gradient fields in the main magnetic field within the examination region, a radio frequency transmit coil assembly for exciting resonance in selected dipoles within a subject disposed in the examination region such that the dipoles generate circularly polarized resonance signals at a characteristic resonance frequency, a radio frequency receive coil assembly for receiving the circularly polarized resonance signals generated by the dipoles, and a reconstruction processor for reconstructing the received signals into an image representation.