Abstract: Disclosed is a device for simply creating a magnetic gradient field having a field-free line (FFL). The device comprises two ring-shaped Halbach arrays formed of permanent magnets, and preferably also a coil arrangement for electrically generating a homogeneous magnetic field for shifting the FFL in a predetermined plane. The FFL can be rotated together with the Halbach array in the plane, without the coil arrangement having to be rotated or moved. The invention is suitable for effective construction of a scanning device for magnetic particle imaging (MPI).

Abstract: The invention relates to a method and an MPIS scanner for tomographic imaging of an object with magnetic particles distributed in the interior of the object, comprising the steps of generating a selection magnetic field with a predetermined magnetic field gradient in at least one field-free point (FFP) in a predetermined scanning plane, generating a time-dependent, periodic excitation magnetic field with a predetermined maximum frequency, repeatedly displacing the at least one FFP along a predetermined closed trajectory with a predetermined repetition time in the scanning plane, moving the object through the scanning plane along a predetermined advance direction with a predetermined advance speed, detecting the change in the magnetization state of the magnetic particles at the points in the object interior through which the at least one FFP passes, reconstructing the local particle concentrations at the points through which the at least one FFP passes in respect of an object coordinate system, interpolating t

Abstract: Disclosed is a device for simply creating a magnetic gradient field having a field-free line (FFL). The device comprises two ring-shaped Halbach arrays formed of permanent magnets, and preferably also a coil arrangement for electrically generating a homogeneous magnetic field for shifting the FFL in a predetermined plane. The FFL can be rotated together with the Halbach array in the plane, without the coil arrangement having to be rotated or moved. The invention is suitable for effective construction of a scanning device for magnetic particle imaging (MPI).

Abstract: The invention relates to a method and an MPIS scanner for tomographic imaging of an object with magnetic particles distributed in the interior of the object, comprising the steps of generating a selection magnetic field with a predetermined magnetic field gradient in at least one field-free point (FFP) in a predetermined scanning plane, generating a time-dependent, periodic excitation magnetic field with a predetermined maximum frequency, repeatedly displacing the at least one FFP along a predetermined closed trajectory with a predetermined repetition time in the scanning plane, moving the object through the scanning plane along a predetermined advance direction with a predetermined advance speed, detecting the change in the magnetization state of the magnetic particles at the points in the object interior through which the at least one FFP passes, reconstructing the local particle concentrations at the points through which the at least one FFP passes in respect of an object coordinate system, interpolating t

Abstract: The shutters (2) in an X-ray device which include at least a radiation source (1), a diaphragm device (8) with shutters (2) and a recording (3) and image processing unit (4), are provided with hole and/or edge patterns (11-14) which reproduce non-anatomical patterns in the radiation image; the shutter edges (15) are detected in the radiation image in the image processing unit on the basis of such patterns, so that only the directly irradiated part of the patient is displayed.

Abstract: The present invention relates to a method for automatically detecting contours of, for example, shutters or implants in an X-ray image. A number of closed paths is derived from the X-ray image, one of said closed paths being selected, in dependence on the contrast along the closed paths, as the contour. The closed paths may be derived from a set of line candidates on which contour pixel candidates are situated. The contour pixel candidates can be derived from a high-pass or gradient version of the X-ray image.

Abstract: The invention relates to an image processing method in which an original image is first decomposed into a series of detail images, with each of which there is associated a respective spatial frequency range, low contrasts being enhanced before assembly of a final image from the images which are produced by the decomposition and are subsequently modified. The modification of the detail images is performed in dependence on the relevant image value as well as in dependence on the mean image value and/or the variation of the image values in a window around the relevant pixel.

Abstract: The invention relates to a method of determining the spatial transformation between an object which is three-dimensionally reproduced by a data set and the object itself. According to the method at least one X-ray image of the object is formed. A pseudo-projection image is calculated for a part of the volume represented by the data set, said pseudo-projection image being compared with the X-ray image. The parameters on which the calculation of the pseudo-projection image is based are varied until optimum registration is achieved.

Abstract: The invention relates to an automatic image analysis method in which two images which have been recorded at different instants are analyzed and a transformation function is determined on the basis of the shifts of image sections, which transformation function describes the shift from one image to another. In order to enable exact determination of this shift, corresponding image sections are determined in the two images by histogram analysis.