Abstract: A method for recording a four-dimensional angiography data record using an x-ray facility with a C-arm is proposed. Projection images are recorded from different projection directions at different time points of the cardiac cycle. A number of three-dimensional reconstruction image data records assigned respectively to a time segment of the cardiac cycle are reconstructed from the projection images and combined to form the four-dimensional angiography data record by temporal assignment in respect of the cardiac cycle. At least one recording parameter describing the temporal sequence is selected when recording the projection images as a function of cardiac stimulation performed to ensure a stable heart rate during recording so that the recording of the projection images takes place in such a manner that it is synchronized with the cardiac cycle.

Abstract: A method for the reduction of artifacts based on an unequal representation of the same material classes in various locations, in particular of cupping artifacts, in a three-dimensional image data set, reconstructed from two-dimensional x-ray projection images is provided. An image datum, describing an attenuation value, is allocated respectively to a voxel, wherein at least two material class regions are located in a post-processing step, which receive, in particular, image data, which is homogeneously distributed and lies in an expected material class interval of the attenuation values, and, considering at least one characteristic of the material class regions, calculates a smooth homogenization function, which is to be applied to the image data of the entire image data set and is applied to the image data of the image data set.

Abstract: A method for correcting image artifacts is proposed. The artifacts occur as a result of an anti scatter grid connected rigidly to an x-ray detector in recording three-dimensional image datasets. Two-dimensional projection images of an object are recorded from different recording geometries for reconstruction the three-dimensional image dataset. A calibration image is recorded for each recording geometry. An average image from all recorded calibration images is established. Subtraction images are established by subtracting the average image from the corresponding calibration images. Noise is removed from the subtraction images. The subtraction images and the average image are stored. A correction image is established for each recording geometry by addition of the subtraction image assigned to the recording geometry and of the average image and is used for correcting the projection image.

Abstract: A method for recording a four-dimensional angiography data record using an x-ray facility with a C-arm is proposed. Projection images are recorded from different projection directions at different time points of the cardiac cycle. A number of three-dimensional reconstruction image data records assigned respectively to a time segment of the cardiac cycle are reconstructed from the projection images and combined to form the four-dimensional angiography data record by temporal assignment in respect of the cardiac cycle. At least one recording parameter describing the temporal sequence is selected when recording the projection images as a function of cardiac stimulation performed to ensure a stable heart rate during recording so that the recording of the projection images takes place in such a manner that it is synchronized with the cardiac cycle.

Abstract: A method for correcting image artifacts is proposed. The artifacts occur as a result of an anti scatter grid connected rigidly to an x-ray detector in recording three-dimensional image datasets. Two-dimensional projection images of an object are recorded from different recording geometries for reconstruction the three-dimensional image dataset. A calibration image is recorded for each recording geometry. An average image from all recorded calibration images is established. Subtraction images are established by subtracting the average image from the corresponding calibration images. Noise is removed from the subtraction images. The subtraction images and the average image are stored. A correction image is established for each recording geometry by addition of the subtraction image assigned to the recording geometry and of the average image and is used for correcting the projection image.

Abstract: The invention relates to a method for evaluating an image dataset obtained by a radiation-based image acquisition device. A scatter background dataset is determined as a function of the image data. The image dataset is corrected pixel by pixel by multiplying the image dataset with the inverse of a function dependent on the quotient of the scatter background data and the image data at a respective pixel. The function is a nonlinear, smooth function determined by a coefficient and having positive derivatives. The absolute value of the function is one for the value zero. The image acquisition parameter dependent coefficient is determined by an optimization process.

Abstract: A conveying device for a vehicle brake system, to convey pressure fluids into at least one vehicle brake, or to convey pressure fluids into a pressure fluid accumulator, or to convey pressure fluids into a master brake cylinder with at least one moveable piston (2) in a receptacle (4) to displace pressure fluids from a working chamber (5?), has at least one non-return valve (9, 9?) to vent the working chamber (5) and to temporarily separate a hydraulic connection between the working chamber (5) and a hydraulic channel, whereby the non-return valve (9) must have at least one valve seat (11) and one valve body (12). To achieve the simplest possible assembly of the non-return valve (9), the valve seat (11) is assembled from several special valve seat segments (13,14).

Abstract: Disclosed are hydraulic/electronic control units (1, 2) for an electronic brake control system. A hydraulic/electronic control unit of current ABS/TCS/ESP systems essentially includes a central hydraulic block (6) and an electronic control unit (1) including control electronics on a control circuit board (4). The circuit board (4) is structured in such a way that it is insulated completely towards the outside on at least one first side (28) and includes an essentially smooth surface. Thus it is possible to use the hydraulic block (6) for cooling the circuit board (4).