Abstract: Upon the detection of a scintillation event at an event pixel, a plurality of associated pixels are identified. Weights are assigned to the event pixel and to all of the associated pixels in such a manner as to attribute the event over an area in a statistically accurate manner. A current sum of all weights which have been previously assigned to each pixel is stored. Unblank signals are generated, based upon this current sum, and the current sum is updated to account for the number of unblank signals so generated.

Abstract: First, second, third and fourth sections of a collimator are arranged to bound an asymmetric interior region. The collimator has one and only one focal point, which is located inside the body to be imaged. The first and second sections are curved and are preferably circular arcs with different radii of curvature. The third and fourth sections are straight.

Abstract: Image data are acquired of an object along a given nominal view direction as well as at other view directions which are slightly off-axis with respect to the nominal view direction. The image data is used to produce an enhanced image of the view along the nominal view direction and to compensate for at least some of the effects of finite angular resolution of the camera collimator.

Abstract: A method and integrator circuit for digitally integrating signals wherein digital signals to be integrated are supplied to a digital adder thereby generating digital adder output signals. Each digital adder output signal is stored and the stored digital adder output signal is refed to the digital adder. Each refed stored digital adder output signal is then added by the adder to a succeeding digital signal supplied to the adder for integration. In a preferred embodiment of the invention, the digital signals are analog-to-digital converted signals produced by a radiation detector, such as a scintillation gamma camera, generated from radiation impinging on the radiation detector.

Abstract: A mechanism for mounting a detector head including a collimator which comprises a supporting structure having a single trunnion axis for the detector head. A shifting mechanism is provided for shifting the detector head and the supporting structure with respect to each other in a manner that the detector head including the collimator is balanced with respect to the single trunnion axis. For overall balancing purposes the supporting structure also comprises a counterweight for the detector head secured to a detector head support arm and a device for varying the position of the center of gravity of the counterweight with respect to a joint moveably supporting the arm.

Abstract: A patient support for scintillation camera imaging applications is formed as a unitary element having a generally constant wall thickness. The element has shoulder, neck and head sections shaped to receive a patient's shoulders neck, and head respectively, and at least two elongated and indented stiffening sections extending between the shoulder section and the neck section. Advantageously, each stiffening section has a bottom wall extending parallel to the surrounding unindented wall and oblique side walls, with gradual transitions between adjacent walls. In a preferred embodiment the unitary element is tiltably interlocked with a patient pallet by means of two offset projecting tabs inserted in mating pallet holes. The tilt angle may be controlled by inserting a wedge between the element and the pallet.

Abstract: A collimator collimates radiation so that each beam passes through two focal lines. One of the lines is in a transaxial plane and the other line is in an axial plane. The focal length in the transaxial plane is longer than is the focal length in the axial plane. In the preferred embodiment, the focal lines are perpendicular, whereby an anamorphic collimator is produced. Alternatively, the focal lines are nonparallel, producing an astigmatic collimator.

Abstract: A thick layer of CsI(Na) is heated to or slightly below its melting point. The CsI(Na) is held at that temperature for 7 to 10 hours and is cooled to room temperature, preferably in two steps. The resulting scintillation crystal is translucent or transparent.

Abstract: A bilateral collimator for rotational camera transaxial SPECT imaging of small body organs produces two different simultaneous views of a body organ to be imaged. The views are produced by groups of passageways which do not intersect each other.

Abstract: A scintillation crystal is provided for a radiation detector, which comprises a first layer of a crystal material having relatively poor mechanical properties, however having a high energy resolution; and a second layer of a crystal material having relatively good mechanical and optical properties. Both layers are arranged in sandwich form.

Abstract: A counterbalanced radiation detection system is provided which comprises a stand and a first and second radiation detectors tiltably connected with the stand. A torque transforming means is connected between the first and second radiation detectors for transforming the torque created by one of the radiation detectors opposite to the torque created by the other radiation detector.

Abstract: From a heart sound signal input the occurrence of a first occurring heart sound is detected. Thereupon a predetermined heart sound enable window time is established, which for a first detection cycle is set to approximately the diastolic interval for the maximum heart rate to be detected. If a second heart sound occurs within this heart sound enable window time, this second heart sound is detected as a systole heart sound. The first heart sound may be detected as a diastole heart sound. If a second heart sound does not occur within the heart sound enable window time the procedure is repeated with increasing heart sound enable time as long as a second heart sound occurs within an increased heart sound enable window time. For diagnostics synchronization signals developed exclusively from the heart sound signals are used to validate data from diagnostic equipment such as a gamma camera.

Abstract: An imaging dynodes arrangement for an electron multiplier, which comprises a first and a second imaging dynodes having dynode cones with a cone tip and a cone base, said dynode cones being connected with each other such that they form free cavities therebetween. Furthermore, there are needle-shaped extraction points arranged at the cone tips of at least the dynode cones of the second imaging dynode. The second imaging dynode is mounted beneath the first imaging dynode in a staggered position such that the cone tips of the dynode cones of the second imaging dynode are seated beneath the cavities of the first imaging dynode, directing the needle-shaped extraction points closely to the cavities. In a preferred embodiment the needle-shaped extraction points protrude into the cavities.

Abstract: A dynodes arrangement for an electron multiplier. It comprises a first dynode having a first voltage input; a second dynode having a second voltage input; and a control grid positioned between the first and second dynodes and having a control voltage input separate from the first and second voltage inputs of the first and second dynodes.

Abstract: A device for detachably securing a collimator to a radiation detector, comprising a first and second annular grooves secured to the radiation detector and the collimator respectively, a split ring having a first and second ring ends and being received in the first annular groove, and a ring diameter control system. The latter one includes a rotating hub and a first and second lever systems connected between the first and second ring ends and the rotating hub. By rotating the hub the ring ends are spread by the lever systems between a first position, where the split ring is alone positioned in the first annular groove, and a second position, where the split ring is arranged in both the first and second annular grooves, thereby attaching the collimator to the radiation detector.

Abstract: A structure for supporting a detector head of a radiation detector which comprises an arm having a distal end supporting the head, a base, a joint mounted on the base and moveably supporting the arm and a slotted member rotatably mounted to the base in a predetermined distance from the joint. The slotted member includes a guidance slot. It also contains a mounting mechanism for mounting the arm in the guidance slot at a desired distance from the rotational axis in a manner that the arm is freely slidable along its longitudinal arm axis, and is non-rotatably fixed with respect to the guidance slot. A motor drive rotates the slotted member about its rotational axis.

Abstract: A radiation detector circuit, which comprises a radiation detector containing a scintillation crystal and a photomultiplier tube for real time photon measurement having a pulse output, and which also includes a plurality of pulse counters each having a pulse input and a count signal output. Between the pulse output of the photomultiplier tube and the pulse inputs of the pulse counters a time multiplexer is provided for connecting each pulse input of each counter in succeeding time periods with the pulse output of the photomultiplier tube. Furthermore, an evaluation circuit is connected with the count signal outputs of the counters for evaluating each count signal of each counter measured during each of said succeeding time periods in the sense of error estimates and trend analysis.

Abstract: A scintillation camera receives radiation from an object under examination and determines the locations of scintillation events. The camera issues x and y coordinate signals which correspond to these locations, and z unblank signals which correspond to the intensity of the scintillation events. Preferably, the scintillation camera can be moved along arc-shaped scanning paths. It is possible to generate a shift movement between the object and the scintillation camera between various pass positions. The output signals of the scintillation camera are forwarded to a display device via an electronic circuitry which encloses a square field of view. This square field of view has a fixed angular orientation with respect to a fixed coordinate system during each of the aforementioned arc-shaped scanning passes.