Abstract: In a computed tomography apparatus, and a method for operating same, for obtaining cardiac images, a spiral scan of a measurement volume containing a patient's heart is conducted, the production of the scanning data during the spiral scanning being synchronized with an ECG signal from the patient, in order to produce a graphic representation of the examination volume, and thus an image of the patient's heart. The ECG signal is employed to control the generation of the data during the spiral scanning at phase of the cardiac cycle wherein minimum movement of the heart takes place. The chronological correlation between the recording of the scanning data and the ECG signal is fixed, so that within each number of successive time intervals, a dataset is obtained completely within that time interval. The datasets from the successive time intervals are then combined to produce an image of the heart.

Abstract: In a method for the operation of a CT apparatus with which volume data for a volume region of an examination subject are registered, markings for identifying reconstruction regions are mixed into an x-ray shadowgram containing the volume region. The reconstruction of image data with respect to each reconstruction region ensues taking reconstruction parameters allocated to the respective reconstruction region into consideration.

Abstract: An X-ray computed tomography apparatus having a two-dimensional detector allows X-ray shadowgraphs to be alternatively produced with using one or several detector rows. For this purpose, a slot diaphragm near the tube and a slot diaphragm near the detector are provided. For the superposition of the shadowgraphs of the individual detector rows, an on-line computing method is used that includes a deblurring filter for the reduction of image blurring due to table motion, and a method for scatter radiation correction in a multirow or matrix detector.

Abstract: A computed tomography apparatus has a surface X-ray detector composed of detection elements, with all detectors being usable in a spiral scan wherein the detector and an X-ray radiator are rotated around a system axis. The detector has a symmetry axis tilted relative to the system axis by a non-zero acute angle, this angle can be adjustable, including being settable to a value of zero for conducting a conventional spiral scan.

Abstract: An apparatus for examining tissue with light, for identifying inhomogeneities, such as tumors, in the tissue, bidirectionally transirradiates the tissue with light, and detects the light emerging from the tissue in the two directions, thereby providing different images of the tissue with the inhomogeneities therein represented with different contrast, thereby making identification of the inhomogeneity easier.

Abstract: In an apparatus and method for examining tissue by transillumination of the tissue, light having different, defined wavelengths is emitted from a plurality of monochromatic light sources into tissue under examination, the light emerging from the tissue is detected by a detector arrangement for detecting the parts of the emitted light transmitted by the tissue, and signals from the detector arrangement are supplied to an evaluation unit. The evaluation unit calculates data with respect to the concentration of the different tissue components in the tissue under examination from the different signals on the basis of stored data that correspond to the light absorption of different tissue components.

Abstract: An x-ray examination apparatus with a detector array having a number of detector elements includes a data correction computer in which the subject-scattered radiation can be numerically determined and corrected. The forward scatter intensity is determined by multiplication of the measured intensities, windowed with a window function, with the natural logarithm of the intensity normalized with the unattenuated primary intensity. The subject-scattered radiation can then be calculated and corrected through filtering of the forward scatter intensity with a convolution kernel and a suitable scaling.

Abstract: In a process for localizing a scintillation event in a gamma camera having a plurality of photomultipliers forming a camera surface, each photomultiplier generating an output signal in response to the scintillation event, wherein a plurality of comparative signal sets are generated from output signals of the photomultiplier corresponding to respective scintillation events of known location, a location-dependent probability function is formed based on a comparison of the outputs of the photomultipliers for a scintillation event of unknown location with the comparative signal sets, and the location of the scintillation event of unknown location is defined as the location corresponding to the maximum of the probability function, the speed with which the localization is accomplished is increased by initially defining a portion of the total gamma camera surface in which there is a high probability that the location of the scintillation event of unknown origin lies, and limiting the investigation for the location o

Abstract: In a method for the localization of scintillation events in a gamma camera with a number of photomultipliers the output signals of the photomultipliers, in dependence on a release signal, are subjected to a pattern recognition process. In the pattern recognition process the output signals are compared with comparative signal sets which each comprise the expected values of output signals from photomultipliers which would be generated by several comparative scintillation events with at respective origins at known locations. The locations of the multiple scintillation events are then registered as the origins that belong to a comparative signal set which presents the greatest similarity value to the output signals in question.

Abstract: A computer tomography apparatus includes an x-ray source which irradiates an examination subject, thereby producing attenuated primary radiation, and scatter radiation. A row of detector elements for the attenuated primary radiation is, during normal operation, disposed behind the examination subject in registry with the x-ray beam. During an examination, the x-ray source and the detector row are rotated around an axis to irradiate the examination subject from different directions. A second row of detector elements, for detecting the scatter radiation, is, during normal operation, disposed next to the primary radiation detector row in the direction of the axis of rotation. During calibration using a standardized scatter element as the examination subject, the primary radiation detector row can be axially displaced to occupy the position normally occupied by the scatter radiation detector row.

Abstract: A computer tomography apparatus has an annular anode surrounding a volume in which an examination subject is disposed, a source for generating an electron beam, and a coil through which the electron beam passes which deflects the electron beam so as to be incident on a face of the anode and to orbit the examination subject, thereby causing the examination subject to be irradiated in a measuring field from various directions. A control unit is provided for the coil causing the electron beam to be deflected so as to sweep the anode in both the azimuthal and radial directions. The focus of the electron beam on the anode surface thus describes a wave-shaped path, so that the focus path on the anode is lengthened and the thermal load is reduced.

Abstract: A method and apparatus for identifying the distribution of the dielectric constants in an object employ radiation emitted by a microwave transmitter directed at the object, which radiation is received by a microwave detector array. The dielectric constant distribution is calculated in a computer from the output signal of the detector array, and is represented on a monitor. The transmitted and scattered radiation is acquired by the array in a prescribed volume in terms of amplitude and phase. For this purpose, the array has a surface with detector elements thereon which is linearly displaceable in a direction toward the microwave transmitter in steps along a selected path. At each step, the incoming radiation is identified in terms of amplitude and phase at a plurality of measuring locations, the number of measuring locations corresponding to the number of individual detector elements within the array. This measuring phase is thereafter combined with a calibration phase for further processing.

Abstract: A method and apparatus for undertaking a non-contacting measurement of the three-dimensional temperature distribution in a non-uniform examination subject direct microwave radiation at the examination subject, detect the three-dimensional phase and amplitude of microwave radiation which is attenuated and scattered by the examination subject, and calculate the three-dimensional dielectric constant distribution in the examination subject on the bases of the detected phase and amplitude values. In a separate step the characteristic thermal radiation of object is measured, too. The three-dimensional temperature distribution of the examination subject is then calculated from both the three-dimensional dielectric constant distribution data and the characteristic thermal readiation data of a selected location.