Abstract: A patient (14), at rest, is injected with a first isotope tracer. After a first uptake period, the patient is stressed and injected with a second isotope tracer. After a second isotope tracer uptake period, first and second isotope imaging data are concurrently detected by data acquiring devices (16). The first and second isotope imaging data are reconstructed into a first or rest state image, a second or stressed state image, and optionally a combined first and second isotope image. The image with the better image statistics is segmented to generate segmentation parameters, which segmentation parameters are applied to both the first or rest and second or stressed state images. In this manner, an image whose image statistics may be too weak for accurate segmentation is accurately segmented by generating two inherently aligned images and applying the same segmentation parameters to both.

Abstract: In a disclosed imaging method, the instantaneous speed or data acquisition dwell times of a detector head is optimized as a function of position along a path of the detector head around a subject. The optimization is respective to an expected radioactive emission profile of a region of interest that is less than the entire subject. The detector head is traversed along the path using the optimized instantaneous speed or data acquisition dwell times. During the traversing, imaging data are acquired using the detector head. The acquired imaging data are reconstructed to generate a reconstructed image of at least the region of interest. A gamma camera configured to perform the foregoing imaging method is also disclosed.

Abstract: In a medical system, at least one medically operative member (10, 12, 100) is configured to interact with or acquire data from a subject (74) disposed in an examination region. An array of photosensors (70, 170) is disposed on the at least one medically operative member. The array of photosensors is arranged to view the examination region. A position-determining member (82, 82a, 82b) is configured to determine a position of at least one optically detectable marker (72, 172) disposed with the subject in the examination region based on light from the at least one optically detectable marker sensed by the array of photosensors.

Abstract: In a disclosed imaging method, the instantaneous speed or data acquisition dwell times of a detector head is optimized as a function of position along a path of the detector head around a subject. The optimization is respective to an expected radioactive emission profile of a region of interest that is less than the entire subject. The detector head is traversed along the path using the optimized instantaneous speed or data acquisition dwell times. During the traversing, imaging data are acquired using the detector head. The acquired imaging data are reconstructed to generate a reconstructed image of at least the region of interest. A gamma camera configured to perform the foregoing imaging method is also disclosed.

Abstract: In a disclosed imaging method, the instantaneous speed or data acquisition dwell times of a detector head (14, 16) is optimized as a function of position along a path (P) of the detector head around a subject (S, SS, SXL). The optimization is respective to an expected radioactive emission profile (EPROI) of a region of interest (H, HS, HXL) that is less than the entire subject. The detector head is traversed along the path using the optimized instantaneous speed or data acquisition dwell times (40). During the traversing, imaging data are acquired using the detector head. The acquired imaging data are reconstructed to generate a reconstructed image of at least the region of interest. A gamma camera (10) configured to perform the foregoing imaging method is also disclosed.

Abstract: A patient (14), at rest, is injected with a first isotope tracer. After a first uptake period, the patient is stressed and injected with a second isotope tracer. After a second isotope tracer uptake period, first and second isotope imaging data are concurrently detected by data acquiring devices (16). The first and second isotope imaging data are reconstructed into a first or rest state image, a second or stressed state image, and optionally a combined first and second isotope image. The image with the better image statistics is segmented to generate segmentation parameters, which segmentation parameters are applied to both the first or rest and second or stressed state images. In this manner, an image whose image statistics may be too weak for accurate segmentation is accurately segmented by generating two inherently aligned images and applying the same segmentation parameters to both.

Abstract: In a medical system, at least one medically operative member (10, 12, 100) is configured to interact with or acquire data from a subject (74) disposed in an examination region. An array of photosensors (70, 170) is disposed on the at least one medically operative member. The array of photosensors is arranged to view the examination region. A position-determining member (82, 82a, 82b) is configured to determine a position of at least one optically detectable marker (72, 172) disposed with the subject in the examination region based on light from the at least one optically detectable marker sensed by the array of photosensors.

Abstract: An imaging system (10) includes at least one radiation detector unit (16) disposed adjacent a field of view (20) to detect and measure radiation from the field of view (20). The detector unit (16) includes multiple detection modules (18) which each detects radiation from a prespecified region of the field of view (20), each region being a fraction of the field of view. One or more pinholes (52) are associated with the detector unit (16). Each pinhole (52) receives radiation from the prespecified region of the field of view (20) and transmits radiation to one or more associated detection modules (18).

Abstract: A radiation imaging device suitable for SPECT or other nuclear imaging includes a detector (22) which receives radiation. A fan beam-slit collimator (20) is positioned adjacent a radiation receiving face (32) of the detector, intermediate the detector and a radiation source (12, 18). The collimator includes a plurality of slats (30) having a common focus. A body (44) adjacent the slats defines one or more elongate slits (46). The slit is arranged such that radiation passes through the slit and between the slats to the detector face. The body is at least substantially impermeable to the radiation. The fan beam-slit collimator (20) enables higher resolution or efficiency to be achieved from the detector.

Abstract: In a disclosed imaging method, the instantaneous speed or data acquisition dwell times of a detector head (14, 16) is optimized as a function of position along a path (P) of the detector head around a subject (S, SS, SXL). The optimization is respective to an expected radioactive emission profile (EPROI) of a region of interest (H, HS, HXL) that is less than the entire subject. The detector head is traversed along the path using the optimized instantaneous speed or data acquisition dwell times (40). During the traversing, imaging data are acquired using the detector head. The acquired imaging data are reconstructed to generate a reconstructed image of at least the region of interest. A gamma camera (10) configured to perform the foregoing imaging method is also disclosed.

Abstract: An imaging system (10) comprises at least one radiation detector unit (16) disposed adjacent a field of view (20) to detect and measure radiation from the field of view (20). The detector unit (16) includes multiple detection modules (18) which each detects radiation from a prespecified region of the field of view (20), each region being a fraction of the field of view. One or more pinholes (52) are associated with the detector unit (16). Each pinhole (52) receives radiation from the prespecified region of the field of view (20) and transmits radiation to one or more associated detection modules (18).

Abstract: A radiation imaging device suitable for SPECT or other nuclear imaging includes a detector (22) which receives radiation. A fan beam-slit collimator (20) is positioned adjacent a radiation receiving face (32) of the detector, intermediate the detector and a radiation source (12, 18). The collimator includes a plurality of slats (30) having a common focus. A body (44) adjacent the slats defines one or more elongate slits (46). The slit is arranged such that radiation passes through the slit and between the slats to the detector face. The body is at least substantially impermeable to the radiation. The fan beam-slit collimator (20) enables higher resolution or efficiency to be achieved from the detector.

Abstract: The invention relates to a computer tomograph provided with a charge-integrating read amplifier having a plurality of gain factors for a data acquisition system as well as a control circuit for the gain factor. In order to avoid noise in addition to the shot noise in computer tomographs of this kind and also to avoid degrading of the DQE (Detection Quantum Efficiency), according to the invention it is proposed that the control circuit automatically selects the gain factor in dependence on the expected integrated input signal of the next frame, the expectation being based on the maximum possible relative variation of the integrated input signal between two successive frames.

Abstract: An x-ray examination apparatus comprises an x-ray image sensor matrix (1) for deriving an initial image signal from the x-ray image. The sensor elements of the x-ray sensor matrix convert incident x-rays into electric charges. These electric charges are read-out and converted into the initial image signal. Further a correction unit (2) is provided for correcting the initial image signal, notably for disturbances due to delayed transferred charges, that have been retained in the sensor elements for some time. The correction unit (2) is provided with a memory which stores correction values. Further the correction provided with a selection unit (5) for selecting appropriate correction values from the memory (3).

Abstract: In order to manufacture a scintillator layer for a detector for the detection of electromagnetic radiation, transmitted by an object, which has a high spatial resolution and only a slight interaction between the scintillator elements, it is proposed to pour a molten mass of a radiation-absorbing metal, having a melting point below 350° C., into intermediate spaces which extend vertically between neighboring scintillator elements.

Abstract: An x-ray examination apparatus comprises an x-ray image sensor matrix (1) for deriving an initial image signal from the x-ray image. The sensor elements of the x-ray sensor matrix convert incident x-rays into electric charges. These electric charges are read-out and converted into the initial image signal. Further a correction unit (2) is provided for correcting the initial image signal, notably for disturbances due to delayed transferred charges, that have been retained in the sensor elements for some time. The correction unit (2) is provided with a memory which stores correction values. Further the correction provided with a selection unit (5) for selecting appropriate correction values from the memory (3).

Abstract: A medical X-ray apparatus is provided with image detector elements 30 which are arranged in a matrix of rows and columns. In order to improve the noise behaviour of the read amplifiers 46 during the reading per row, a plurality of column conductors 36 is provided per column so that the read time is prolonged in proportion to the number of column conductors and the stray capacitance is reduced proportionally. Both steps reduce the noise in known manner. In the case of an integrated implementation, the conductors for driving the reading per row cannot be arranged arbitrarily close to one another because of their mutual capacitance, so that these conductors require a comparatively large surface area.

Abstract: An x-ray examination apparatus comprises an x-ray detector with a sensor matrix for deriving an image signal from an x-ray image. The x-ray detector is provided with a scatter grid having a regular pattern of x-ray attenuating partitions. The spatial resolution of the sensor matrix is such that the size of the smallest detectable detail in the x-ray image is larger than the distance between adjacent partitions. In particular the x-ray detector comprises an x-ray sensitive photoconductor layer for converting x-rays into electric charges, separate sensor elements include respective collecting electrodes and a semiconductor cladding layer being disposed between the photoconductor layer and the collecting electrodes. The semiconductor cladding layer has a substantial lateral electric conductivity. For example, the semiconductor cladding layer is a chlorine doped selenium layer, or a selenium, sulphur or telluride doped lead-oxide layer.

Abstract: An image detection device, notably a semiconductor image detection array for detecting x-ray images, is provided wherein perturbations due to phantom-images are substantially mitigated. In such an image detection array incident image carrying radiation is converted into charges. Delayed charge transfer due to trapping of charges in the semiconductor material of radiation sensor elements causes such perturbations. In an image detection device according to the invention a correction circuit is provided which is arranged to form an image correction signal being representative of delayed transferred charges. In a particular embodiment of an image detection device according to the invention the image correction signal is formed as a superposition of exponentially decaying signals of images which were detected before the detection of a currently detected image.