Abstract: A method for generating image data relating to a virtually prescribable X-ray tube voltage U3 from first and second dual energy CT image data is disclosed.

Abstract: A method is for determining a parameter in an image area as a measure of a homogeneity of a substance in an object, and to a method for segmenting a substance in an image that uses the parameter as an additional segmentation criterion. In the method, at least two X-ray images are acquired in relation to different energies E1, E2 of an X-radiation, and the parameter is determined from the statistical distribution of attenuation values Di(E1),Di(E2) where i=1, . . . , N in the image area such that faulty classifications can be avoided in a simple way during the segmentation.

Abstract: A method is disclosed for scattered radiation correction in x-ray imaging devices having a number of x-ray sources that can be moved around an examination object in at least one scanning plane during a measurement pass. During the measurement pass, a number of x-ray projections are recorded at different projection angles with simultaneous use of the x-ray sources. In at least one embodiment of the present method, parameters characterizing an outer object contour are determined in the scanning plane from measured data of different x-ray projections.

Abstract: A method and an image reconstruction device are disclosed for reconstructing image data on the basis of input projection data obtained via an X-ray computerized tomography system. A target convolutional kernel is selected, which, when reconstructing image data from the input projection data using simple filtered back projection, would lead to target image characteristics. Image data is then reconstructed using an iterative reconstruction method of at least one embodiment.

Abstract: A method is disclosed for reconstruction of image data of an object under examination from measurement data, with the measurement data having been recorded during a rotating movement of a radiation source of a computed tomography system around the object under examination. The radiation source emits focal and extra-focal radiation. In at least one embodiment of the method, the image data is determined from the measurement data by use of an iterative algorithm. A variable is used in the iterative algorithm which contains a distribution of the extra-focal radiation.

Abstract: A method and a device are disclosed for generating a CT image with a high time resolution using a computed tomography scanner which has at least two recording systems which are operated at different X-ray energy spectra. In at least one embodiment of the process, CT images are firstly reconstructed in each case from a semi-rotation with the two recording systems, with irradiated lengths of the contrast agent-enriched structures and the soft tissue being calculated therefrom. Subsequently, a common X-ray energy is assumed and artificial measurement data records are calculated therefor, using the knowledge of the irradiated lengths for both recording systems at the same common X-ray energy. The artificial measurement data of respectively a quarter-rotation per recording system is then used to calculate the final CT image with a high time resolution. The method affords the use of dual-energy scans without losing the high time resolution available in dual-source systems.

Abstract: A multi-emitter computed tomography scanner is disclosed, including a plurality of x-ray emitter/detector arrangement pairs arranged offset at an angle to one another. In at least one embodiment, the detector arrangements of the pairs are designed to be energy selective.

Abstract: A method is for generating tomograms of a cyclically and complexly moving examination object using a tomography unit that reconstructs tomograms in at least one slice plane from detector output data. At least two tomograms from different phases of the movement cycle of the examination object are reconstructed in the region of at least one slice plane. The tomograms are subdivided automatically into subregions with good and bad image quality, and at least one complete tomogram is assembled from subregions with relatively good image quality per slice plane.

Abstract: A computed tomography device (CT device) includes a user interface, via which the standard settings characterizing the CT measurement can be performed. At the same time, in a method and a computed tomography device for carrying out this method, filtering behavior of the filter electronics is adapted to the configuration of the standard settings by the system computer.

Abstract: A method is disclosed for compiling computer tomographic representations using a CT system with at least two angularly offset ray sources. A first ray cone with a relatively larger fan angle and a second ray cone with a relatively smaller fan angle scan an object circularly or spirally. The first ray cone generates a first dataset A and the second ray cone generates a dataset B. The dataset B of the smaller ray cone is supplemented with other data at the edge to give an expanded dataset B+ for reconstruction of the CT representation. The expanded dataset B+ of the second, smaller ray cone and the dataset A of the first, larger ray cone is subjected to a convolution operation to give datasets B+? and A?. Finally, a back projection to reconstruct sectional images or volume data is respectively carried out from the convoluted datasets B+? and A?. The dataset B is supplemented with data of the dataset A and supplementary data are removed from the dataset B+? after the convolution but before the back projection.

Abstract: An x-ray system is disclosed including a selector for finding an optimum combination between the contrast medium and the energy spectrum of an x-radiation for a scan to optimize the noise-to-contrast ratio. A method for creating X-ray images is also provided. The x-ray images are created with the aid of contrast media by taking into account an optimal combination between the contrast medium and the energy spectrum of an X-radiation used for a scan. A method for the use of a lanthanide-containing complex to produce a contrast medium for optimizing the combination between the contrast medium and the radiation to obtain a maximum contrast-to-noise ratio in an X-ray image is also provided.

Abstract: A method is disclosed for detecting X-ray radiation from an X-ray emitter. In at least one embodiment of the method, an electric pulse with a pulse amplitude characteristic of the energy of a quantum is generated when a quantum of the X-ray radiation impinges on a sensor, wherein a number of threshold energies are predetermined. When the pulse amplitude corresponding to the respective energy is exceeded, a signal is emitted each time the pulse amplitude corresponding to a respective threshold energy is exceeded. At least one embodiment of the method permits reliable and high-quality imaging, even in image regions with high X-ray quanta rates. To this end, at least one of the threshold energies is predetermined such that it is higher than the maximum energy of the X-ray spectrum emitted by the X-ray emitter.

Abstract: A method is disclosed for generating computed tomography image data of a volume of interest from X-ray CT data sets generated by a computed tomography system during scanning of an examination subject on a helical path rotating around a longitudinal system axis in the infeed direction.

Abstract: A method is disclosed for image reconstruction of an object with the aid of at least one-dimensional projections of the object into a three-dimensional volume image data record, it being possible to generate the projections by at least one detector/source system with reference to different positions and angles relative to the object, and at least two projections forming a reconstruction volume in an overlap region as basis for a backprojection of the projections into the three-dimensional volume image data record, in particular computed tomography. An apparatus for carrying out the method is further disclosed. In at least one embodiment, supplemented reconstruction volumes are generated by supplementing reconstruction volumes, covered only partially by projections, by way of virtual projections that are derived from volume image data records.

Abstract: A method for generating image data relating to a virtually prescribable X-ray tube voltage U3 from first and second dual energy CT image data is disclosed.

Abstract: A method is disclosed for reconstructing CT image data. In at least one embodiment, the method includes providing measured CT projection data p based on the CT projection data p, reconstructing first CT image data fk=1, and on the basis of the first image data fk=1 iteratively generating k+1-th CT-image data according to the formula: fk+1=fk??(Q(Pfk?p)+?R(fk)) until the standard ?fk+1?fk?2 is ?n, with the reconstruction operator Q containing a noise weighting according to Q=B·Wstatist.·H. Aside from suppressing “cone” artifacts, the proposed method of at least one embodiment indicates a significant reduction in the image noise even after a few iterations.

Abstract: The present invention relates to a method for scattered radiation correction in X-ray imaging, and to an X-ray imaging system for carrying out the method. In the method, measurement signals t from an X-ray detector (9) are digitized and converted to logarithmic form, with these measurement signals t having been obtained by radiation through an examination object (10) by the X-ray detector (9). Correction values which have been obtained from a series development of a logarithm ln(1?s/t) are subtracted from the measurement signals that have been converted to logarithmic form, with this series development being terminated at the earliest after the first order, where s denotes a previously determined scattered radiation signal from radiation passed through the examination object (10). The method and the associated X-ray imaging system allow scattered radiation to be corrected for with increased accuracy, on the basis of measurement signals that had been converted to logarithmic form.

Abstract: A radiation detection unit is disclosed for a computer tomograph, and a computer tomograph having a radiation detection unit is also disclosed. In at least one embodiment, the radiation detection unit for a computer tomograph includes at least one scattered radiation sensor, set up and arranged to measure scattered radiation.

Abstract: A detecting apparatus is disclosed for detecting an object by way of a projection through the object onto a detection plane. In at least one embodiment, the detecting apparatus has a transmitter that is designed to emit quanta. In at least one embodiment the detection apparatus also has a detector, arranged in a detection plane, for detecting the emitted quanta, the detector being designed and arranged to generate at least one detector signal at least partially representing the object in a projection, as a function of the quanta received through the object. In at least one embodiment, the detecting apparatus is designed to generate as a function of the generated detector signal for a detected quantum a quantum signal that represents the quantum energy of one detected quantum. Finally, in at least one embodiment the detecting apparatus is designed to generate a sum signal that corresponds to a sum of the quantum energies of the quantum energies represented by the quantum signals.

Abstract: Methods for post-processing raw detector signals of an x-ray or gamma detector are disclosed. According to at least one embodiment of the invention, raw detector signals are filtered, an associated filtered signal is determined at least for a subset of the raw detector signals, and those filtered signals whose signal value is less than zero are then respectively replaced by a signal value greater than zero.