Abstract: A computed tomography method and apparatus are provided wherein a radiation source moves circularly relative to an examination zone about an axis of rotation (14). The radiation source produces a cone beam of x-rays and the focal point of this cone beam is switched between at least two positions (23a, 23b) spaced apart from each other and arranged on a line parallel to the axis of rotation to enlarge the reconstructable examination zone parallel to the axis of rotation. Preferably, the image of the examination zone is reconstructed using an iterative reconstruction method, in particular an algebraic reconstruction method or a maximum likelihood method.

Abstract: A tomographic apparatus (10) includes radiation source (20), at least one radiation sensitive detector (30), and a reconstruction system (40). The radiation source (20) sweeps along a z-axis (16) and returns to its initial position in coordination with about two revolutions of the radiation source (20) about an imaging region (32) with a frequency of about half a frequency of a revolution of the radiation source (20) about the imaging region (32). The at least one radiation sensitive detector (30) detects radiation emitted by the radiation source (20) that traverses a volume of interest (52) within the imaging region (32) and generates data indicative of the detected radiation. The reconstruction system (40) reconstructs the detected data to generate an image of a subject in the volume of interest (52).

Abstract: A radiation image capturing apparatus includes an image capturing device having a tomosynthesis control mechanism for moving a radiation source and a radiation conversion panel, which are disposed on the respective opposite sides of a subject, respectively in opposite directions in synchronism with each other, a longitudinal direction moving mechanism for moving an image capturing range of the image capturing device in a longitudinal direction of the subject, an image reconstructing unit for generating a single three-dimensional image from a plurality of radiation images captured in a single image capturing range, an image joining unit for joining a plurality of three-dimensional images generated by the image reconstructing unit with respect to a plurality of image capturing ranges, in the longitudinal direction of the subject, and a projection image generating unit for generating a two-dimensional projection image on an arbitrary image plane based on a joined three-dimensional image.

Abstract: A high-speed biplane radiography system for in-vivo assessment of joint function is provided. The system can acquire stereo-pair radiographic images at rates from 30-4000 frames per second of nearly any motion or joint. The radiographic equipment can be mounted in a gantry system that provides sufficient positioning flexibility for imaging different joints of a subject's body, along with an imaging area large enough for a variety of dynamic activities (e.g., walking, running, jumping, throwing, etc.). Three-dimensional (3D) bone positions can be determined using software for matching the bones in each X-ray image with 3D models developed from subject-specific CT (computed tomography) scans. This system can provide accurate (e.g., ±0.1 mm) assessment and direct 3D visualization of dynamic joint function, and can overcome limitations of conventional gate or motion analysis.

Abstract: A method for creating, displaying, and analyzing X-ray images of a plurality of objects is disclosed. The method comprising, for each of the objects recording three-dimensional X-ray image data of the object in a single measurement; creating a three-dimensional X-ray image of the object from the three-dimensional X-ray image data; creating one or two two-dimensional X-ray images of the object from the three-dimensional X-ray image data; displaying the one or two two-dimensional X-ray images of the object; and analyzing the one or two two-dimensional X-ray images of the object. For a subset of the plurality of objects the three-dimensional X-ray image of the object is displayed, wherein the subset of the plurality of objects is determined based on the step of, for each of the objects, analyzing the one or two two-dimensional X-ray images of the object.

Abstract: A method is for taking computed tomography scans with the aid of a CT unit and to a CT unit. An X-ray tube is moved in a circle or spiral about a z-axis in combination with a detector situated opposite and an object is scanned. The X-ray tube includes a jumping focus with two or more different jumping focal positions relative to the X-ray tube. Parallel data records are formed from the detector data obtained, and tomograms are reconstructed therefrom. When forming the parallel data records, account is taken of the different position of the respectively current jumping focus in relation to the X-ray tube (=jumping focal position) in the radial direction.

Abstract: A detector module, in at least one embodiment, is disclosed for x-radiation or gamma radiation that includes one or more optical waveguide sections that are arranged next to one another in order to form one or more detector rows and are optically interconnected in serial fashion. The waveguide sections include one or more converter materials for converting incident x-radiation or gamma radiation into optical radiation and are designed in such a way that optical radiation of different wavelength is generated in respectively neighboring regions along the waveguide sections upon incidence of x-radiation or gamma radiation. The present detector module, in at least one embodiment, can be implemented cost effectively with a high number of detector rows, and is of very low weight.

Abstract: A laminography inspection system comprises an irradiation source, a plurality of linear image detectors defining an image plane, a fixed table for placement of a test object in a stationary position between the irradiation source and the image detectors, and a computing device for processing a plurality of images of the test object acquired from the image detectors. The irradiation source and the image detectors perform a plurality of parallel linear scanning passes across the area of the test object to acquire images of the test object under different viewing angles. Based on the acquired image data, the computing device determines a warp compensation and generates a cross-sectional image of a selected section within the test object.

Abstract: The invention relates to a system and a method for medical navigation. In order to reduce the time required for medical navigation for transcutaneous interventions, the invention proposes that the position of a medical instrument (5) in an object (4) be determined with the aid of projection images (13, 14), and that the position be indicated in a three-dimensional structural image (11). The invention can be carried out in particular with C-arc X-ray appliances and CT X-ray appliances.

Abstract: The pipe inspection method and apparatus can be used to implement rapid, tomographic inspection of a pipe set up at a narrow location. The pipe inspection method of the present invention includes: a first step for scanning the pipe by translating a radiation source and radiation detector arranged opposedly to the pipe; a second step for the radiation detector to detect radiation that the radiation source has emitted, at given scanning distance intervals; a third step for creating a transmission image of the pipe, based on a radiation dose that the radiation detector has detected; and a fourth step for constructing a tomogram or stereoscopic image of the pipe, based on the transmission image. According to this invention, it is possible to provide the pipe inspection method and apparatus that can be used to implement rapid, tomographic inspection of the pipe set up at a narrow location.

Abstract: A CT scanner according to the present invention is particularly adapted for scanning the extremities of a patient. The CT scanner includes an x-ray source and x-ray detector mounted for rotation and translation along an axis parallel to a table for supporting the patient's extremity. The source and detector are mounted opposite one another on an inner circumference of an inner ring. The inner ring is rotatable about the axis within an outer ring mounted on at least one carriage. The carriage is movable parallel to the axis. During scanning, the inner ring rotates within the outer ring while the rings and carriage move along the axis, thereby producing a helical scan of the extremity.

Abstract: The present invention relates to an apparatus for nuclear medicine imaging in which the imaging platform is attached directly to the detectors for nuclear imaging to allow for minimal constant distance between the detector(s) and the object to be imaged. As the detector moves around the object to be imaged to capture different angular views of the object, the imaging platform is rotated in a compensatory manner to maintain a its long axis perpendicular to gravity during movement of the detector. An advantage of this configuration over prior systems is the ability to obtain multiple angular projections while the distance between the detector and the object being imaged is maintained at a minimum, but the danger of detector-object collision is minimized and the necessity for orbital path calibration to preserve precision of detector movement and distance is eliminated.

Abstract: A magnetic navigation system for orienting a magnetically responsive medical device in a selected direction within an operating region in a subject's body. The system includes a support for supporting the subject, a magnet system a magnetic field to the operating region, and an imaging system. The magnet system includes at least two magnets disposed on opposite sides of the operating region for applying a magnetic field of at least 0.08 Tesla in any selected direction in the operating region by a change of the position and/or orientation of the magnets within an exclusion zone volume. The imaging system includes an imaging beam source and an imaging beam detector disposed on opposite sides of the operating region. The source and the detector being carried on a C-arm which can pivot about an axis generally parallel to the longitudinal axis of the subject to change the imaging angle.

Abstract: A method for producing a CT image by applying Z-filtering to axial scan data collected using a multi-row detector, wherein second axial scan data is collected at a second position Z2 to which an X-ray tube and a multi-row detector are rectilinearly moved relative to a subject to be imaged from a first position Z1 toward an end of the multi-row detector, projection data corresponding to a central portion a2 of a reconstruction field P3 near the end of the multi-row detector is extracted from the second axial scan data, and Z-filtering is applied based on the projection data of reconstruction fields P1, P2 and P3 to produce one CT image.

Abstract: An oblique-view cone-beam CT system comprising an X-ray source for irradiating an object with X-ray from an oblique direction with respect to a rotational axis of said object. A detector is provided for detecting projection images resulting from the X-ray irradiation. A computer electrically connected to the detector is provided for recording the detected projection images and reconstructing the recorded projection images to provide a 3-dimensional image.

Abstract: An x-ray measuring apparatus comprises an x-ray source, an x-ray detector, a rotating device, and a processor. The x-ray source generates x-rays to be emitted to a subject. The x-ray detector detects measurement data regarding the subject. The rotating device changes a relative position of the x-ray source and the x-ray detector with respect to the subject. The x-ray detector is shifted by a distance shorter than half the length of the x-ray detector along a line parallel to the plane of rotation, in a tangential direction of the plane of rotation generated by the x-ray source. The processor obtains projection data by executing a logarithmic converting process for the measurement data, multiplies a value of the projection data by a weight, and obtains reconstructed data therefrom.

Abstract: A portable radioactive-material detection system capable of detecting radioactive sources moving at high speeds. The system has at least one radiation detector capable of detecting gamma-radiation and coupled to an MCA capable of collecting spectral data in very small time bins of less than about 150 msec. A computer processor is connected to the MCA for determining from the spectral data if a triggering event has occurred. Spectral data is stored on a data storage device, and a power source supplies power to the detection system. Various configurations of the detection system may be adaptably arranged for various radiation detection scenarios. In a preferred embodiment, the computer processor operates as a server which receives spectral data from other networked detection systems, and communicates the collected data to a central data reporting system.

Abstract: A method of examining a patient is provided. The method includes imaging a patient utilizing a computed tomography imaging modality, the patient between the pencil-beam x-ray source and the x-ray detector, and imaging the patient between the pencil-beam x-ray source and the x-ray detector using a nuclear medicine imaging modality.

Abstract: A diagnostic X-ray system has an X-ray source that generates an X-ray conical beam, and a panel detector, which has numerous X-ray detection elements arrayed two-dimensionally, opposed to each other so that they can be rotated about the body axis of a subject. CT images of the subject are reconstructed based on projection data acquired by scanning the subject. The panel detector can be offset so that the center of the detecting surface of the panel detector extending in a direction perpendicular to the body axis can be displaced in a direction substantially perpendicular to a reference plane defined with an extension of a straight line linking the focal point of X-rays and a point on the body axis of the subject and with the body axis of the subject.

Abstract: An apparatus for use with a combined CT-PET system wherein a CT source and detector are mounted to a front end of a CT support and the support forms a parking space about a translation axis, a PET detector is mounted to a rear end of the support and a collimator support extends from the PET detector at least part way into the parking space, a collimator is mounted to the collimator support for movement between first and second positions inside the PET detector and outside the PET detector and at least partially within the parking space, respectively, a radiation blocking shield is mounted to the PET detector opposite the CT support to block radiation from that direction from being detected by the PET detector.

Abstract: In one form, the present invention is a method for rapidly resampling a three-dimensional volume of data to permit efficient interactive viewing and visualization of the data is provided in which a set of parallel line segments defining a surface having a constant slope in at least one direction and intersecting the three-dimensional volume are selected and the data is processed at points on the parallel line segments to generate a reformatted image of the data. A corresponding apparatus embodiment is provided. Processing of data can proceed quickly because it is not necessary to check the parallel line segments during processing of the points on the segments to determine whether the points are within a given data volume.

Abstract: An x-ray system using a slot-shaped detector having n rows and m columns of pixels, where n<<m, and providing a variety of relative motions between a patient table and a source-detector unit, including translation along the length of the table, translation across the table, and rotation about the focal spot, and processing the pixel values in a variety of ways to produce information such a shadow graphic x-ray images, tomosynthetic images of surfaces that need not be planar, and bone density estimates. In another embodiment, tomographic images can be obtained directly, using a post-patient collimator that passes nearly all of the primary beam to the imager while eliminating nearly all of the scatter. A feedback loop can equalize the exposure for selected parts of the image substantially in real time.

Abstract: A continuous rotation sampling scheme for use with a nuclear medicine gamma camera facilitates collection of transmission and emission data leading to a reduced overall scan time. The gantry (16) contains a plurality of radiation detector heads (20a-20c) with planar faces and at least one adjustably mounted radiation source (30a). During transmission data collection, the gantry (16) continuously rotates about a subject receiving aperture (18) while the radiation source (30a) continuously rasters back and forth across the field of view. The detected transmission radiation (32a) is reconstructed into an attenuation volumetric image representation by a transmission reconstruction processor (64t). The transmission reconstruction processor (64t) performs a fan beam reconstruction algorithm in each of a multiplicity of planes perpendicular to an axis of rotation.

Abstract: In an X-ray imaging system, an arrangement is provided for readily aligning the system detector with the X-ray beam field, i.e., the projection of the X-ray beam into the plane of the detector. The arrangement is adapted for correcting or compensating for distortion which results from X-ray beam angulation, wherein the beam is projected toward the detector plane at an angle of less than 90°. Initially, the system X-ray tube is positioned to project the X-ray beam at a given beam direction angle &phgr;. A beam width angle &ggr;1 is then computed, from the given angle &phgr; and from specified values of the source-to-image distance and the length of the projected beam field. Thereupon, an offset value is determined from &ggr;1, &phgr; and the source-to-image distance to locate the geometric center of the beam field, and the center of the detector is aligned therewith.

Abstract: In one embodiment, the present invention is a method for positioning an x-ray beam on a multi-slice detector array of an imaging system in which the detector array has rows of detector elements and is configured to detect x-rays in slices along a z-axis. The method includes steps of comparing data signals representative of x-ray intensity received from different rows of detector elements and positioning the x-ray beam in accordance with a result of the comparison.

Abstract: In order to make an X-ray impinging position coincide with a fixed position from the beginning of a scan, in scanning a subject to be examined by an X-ray emitting/detecting apparatus, an X-ray focus position is predicted based on the temperature of an X-ray tube 20 prior to beginning the scan and scan conditions intended to be currently used, and the position of a collimator 22 or an X-ray detector 24 is adjusted so that the X-ray impinges upon a fixed position on the X-ray detector 24.

Abstract: A CT apparatus with alternating focus, in which the detector elements deliver output data when picking up individual projections corresponding to the beam attenuation of the X-rays proceeding to the detector element, the number of data items correspond to twice the number of detector elements participating in the pick-up of each projection. The output data are converted into image reconstruction data, which contain a number of data items per projection which is greater than twice the number of detector elements participating in the pick-up of the respective projection.

Abstract: A method of producing complex motion or spiral tomography images in tomographic imaging, comprising the steps of positioning an object to be imaged in a fixed position, arranging a radiation source on one side of the object to be imaged, arranging a detector on a second diametrically opposed side of the object to be imaged from the radiation source, the detector receiving radiation from the radiation source, while the radiation is being received, rotating the radiation source and the detector substantially around a vertical axis passing through the object to be imaged in a controlled manner whereby a tomographic effect is produced, while the radiation is being received, moving the radiation source in a first vertical direction, while the radiation is being received and simultaneously with the step of moving the radiation source, moving the detector in a second vertical direction opposite from the first vertical direction, and wherein the radiation source and the detector are moved independently from one anoth

Abstract: An X-ray tomosynthesis system as an X-ray diagnostic system is provided. The system comprises an X-ray generator irradiating an X-ray toward a subject, and a planar-type X-ray detector detecting the X-ray passing through the subject and outputting two dimensional imaging signals based on the detected X-ray. The system comprises a supporting/moving mechanism supporting at least one of the X-ray generator and the X-ray detector so that the at least one is moved relatively to the subject.

Abstract: The present invention, in one form, is a system for correcting thermal drift in an imaging system. More specifically, a correction algorithm determines an adjusted focal spot position based upon a first temperature focal spot position and a second temperature focal spot position. The adjusted focal spot position is utilized in the reconstruction process to correct for focal spot movement resulting from thermal drift.

Abstract: An X-ray computed tomography apparatus has a radiation detector composed of X-ray converters so that the scattering of light in a scintillator or the inductive disturbance in a directly converting semiconductor is minimized or eliminated. Each X-ray converter, e.g. a scintillator is in fixed contact with a number of signal converters, e.g. photodiodes. From the output signals of the signal converters, the unsharpness can be calculated and then compensated.

Abstract: An improved data acquisition system filter, optimized for the time domain and for use in a computed tomography scanner of the type using x-ray focal spot wobble, includes a filter time response F(t) which is a function of the waveform w(t) used to drive the focal spot from one position to the other.

Abstract: The method of the present invention combines an ensemble of truncated partial cone beam projections to synthesize a complete virtual projection. The individual partial projections are obtained with CT scanners, where for each partial projection the investigated object is positioned at precise locations specified by formulas described in the present application (e.g., formulas (3), (4), (6) and (18) for linear cone beam synthetic scanner arrays or formulas (9)-(13), (20), (21) and (25)-(27) for circular cone beam synthetic scanner arrays). Prior to the actual reconstruction, the partial cone beam projections are combined to form a complete virtual projection, equivalent to a projection one would obtain by using a sufficiently large detector.

Abstract: The present invention, in one form, is a method of determining focal spot position in a computed tomography system using conventional scan data. The computed tomography system includes, in one embodiment, a bowtie filter attenuating an x-ray beam along two symmetrically disposed raypaths. The symmetrical raypaths impinge upon respective detector channels at identifiable path lengths. The raypath lengths are compared to determine whether the focal spot has shifted.

Abstract: A method for controlling output of an x-ray source to optimize x-ray energy arriving at an associated x-ray receptor during linear tomographic examination. The method comprises the steps of selecting tomographic sweep parameters, predicting a set of x-ray source control parameters based, at least in part, upon the selected tomographic sweep parameters, and controlling x-ray source output in accordance with the set of x-ray source control parameters to optimize x-ray energy arriving at the associated x-ray receptor. Apparatus for controlling output of an x-ray source is also disclosed.

Abstract: A tangential computer tomography scanner for scanning an object having a cross-section. A radiation source emits a beam of penetrating energy. The beam penetrates an object located within the beam and is received by an array of detectors located opposite the source. A drive device moves the beam relative to said object. The array and the source are arranged so that the beam is maintained perpendicular to the cross-section of the object. The tangential computer tomography scanner generates a full volume data set in a single pass.

Abstract: Process and installation making it possible to reconstitute precise images of an area of interest (2) of an object (1) by reducing the errors produced by the contribution of the compliment of the object. A first series of measurements is carried out, where a conical beam (10) only takes in the area of interest of the object (2) and this is followed by a second series of measurements in which the beam takes in the entire object. A combination of the measurements of the two series is carried out in order to make them compatible and obtain a more accurate image of the area of interest (2).

Abstract: A rotational drive sensor 31 which allows a radiation source 10 and a twomensional sensor 20 which are caused to be in one body to turn round a subject 50. An X-ray vessel 13 irradiates X-rays to the subject 50 in a pulsated manner. An X-ray/light conversion element 21 converts an X-ray transmitted image to an optical image. A CCD camera 23 picks up this optical image. An information processing unit 40 reconstructs a three-dimensional pictorial image on the basis of two dimensional pictorial images in plural directions obtained, and a display monitor 46 displays this three-dimensional pictorial image. A controller 39 controls the distance between the X-ray vessel 13 and the X-ray/light conversion element 21 and the focal size of the X-ray vessel 13 on the basis of the size of the subject 50.

Abstract: A computed tomography apparatus includes a gantry rotatable about an object being imaged, an X-ray source mounted on said gantry in opposing relationship to an array of X-ray detectors. An X-ray controller causing emission of X-rays from the X-ray source to shift between the two focal spots to produce first and second sets of projection data. X-rays are emitted from a first focal spot of the source while one projection of the object is acquired. Then the operation of the source is altered to emit X-rays from a second focal spot and the gantry is rotated by one-half the pitch of the detectors. Another projection is acquired at the new gantry position. Additional projections are acquired by alternately emitting the X-ray beam from the two focal spots and advancing the gantry by equivalent amounts between each acquisition.

Abstract: A CT scanner using a rotate-rotate mode wherein the detector is designed to simultaneously detect X-rays that have traversed multiple-planar sections in a patient being scanned.

Abstract: An X-ray computer tomography system with a ring anode and substantially without mechanically moving parts for the production of fast image slices from the inside of an object is improved in such a way that a detector ring is comprised of two adjacent parallel partial detector rings of substantially equal size, whereby the detector ring is arranged within and coplanar to the anode ring. The two partial rings of the detector ring are displaced in a direction largely pependicular to the scan slice so that a ring-shaped detector ring gap is formed between them through which the fan beam coming from the focal spot on the anode passes.

Abstract: A configuration for three-dimensional cone beam computerized tomography imaging which allows a complete data set to be acquired in a practical manner, while providing fast data acquisition to minimize motion artifacts. An object within a field of view such that every plane passing through the field of view passes through the source scanning trajectory at least once.

Abstract: A configuration of three-dimensional cone beam computerized tomography imaging which minimizes the incompleteness of the data set acquired, while providing fast data acquisition to minimize motion artifacts. An object within a field of view is scanned, preferably simultaneously, along a pair of circular source scanning trajectories spaced a distance selected to minimize the amount of missing data. A procedure is disclosed for calculating the spacing distance between the scanning trajectories which minimizes the amount of missing data. In one embodiment, a pair of cone beam x-ray sources are employed and a corresponding pair of two-dimensional array detectors. In order to reduce interference caused by x-rays from one source interacting with the detector corresponding to the other source, the cone beam x-ray sources are angularly offset, for example by 90.degree..

Abstract: An X-ray stand includes a fixture attached to the ceiling surface floor surface or side wall surface of a hospital room. A support is connected to the fixture with a rotary bearing connected to a circular track. An arcuate carriage sliding in the track has a radiation source and receptor respectively at its ends which are aligned on a radiation axis through a patient position. The rotational axis of the bearing is inclined at a substantial angle to the fixture and to the wall to which the fixture is attached so that, when the one end of the arcuate carriage is in a position near the ceiling or other wall, rotation around the bearing axis will rotate the radiation axis through substantially different angles through the patient position.

Abstract: A computer tomography apparatus has an x-ray source which emits a fan-shaped x-ray beam which irradiates a slice of an examination subject. The x-ray source is rotatable around the examination subject to irradiate the slice from different angular directions in the plane of the slice. A row of detector elements is disposed to receive radiation attenuated by the examination subject as the x-ray source rotates around the patient. The radiation detector is disposed on a ring which is rotatable around the examination subject separately from the x-ray source. This permits to meet the conditions of the sampling theorem, applied to the projections with the focus as projection center, without increasing the number of defectors.

Abstract: An industrial CT apparatus capable of obtaining a good image quality by a simple configuration. The apparatus is the second generating type incorporating the rotational motions as well as the traverse motions, in which the detector is positioned nearby a center of rotation of the object to be examined. When the object to be examined is a ring shaped object, the detector is positioned inside the center bore of the object. Also, the X-ray is emitted in a form of fan shaped beam whose symmetrical axis is deviated from an axial direction perpendicular to the traverse direction.

Abstract: A high speed communication apparatus for a computerized axial tomography (CAT) scanner utilizes large diameter slip rings to permit continuous rotation of a rotatable gantry. A communication signal is applied at a first point on one slip ring, and is terminated by a resistive termination at a point 180.degree. opposite the driving point. The communication signal may then be received at any point on the slip ring. The drive and termination connections to the slip ring may be made by brushes, with the receive connection being made by a physical connection to the slip ring. Alternately, the drive and terminate connection may be made by physical contact, with the receive connection being made by a brush.

Abstract: A scanner assembly having a C-shaped gantry rotatably supported by a support head. An x-ray source and a detector assembly are mounted on said gantry for independent movement with respect to one another along said gantry.

Abstract: Accordingly, the present invention provides an x-ray tomography apparatus having a patient table, x-ray tomography components located around the patient table and in an imaginary plane which intersects the table, and structure for supporting the table and tomography components and including apparatus for moving the tomography components along at least a portion of the table. In an alternate embodiment, an x-ray tomography apparatus includes an annular x-ray tomography system for continuously rotating around a patient, which structure has an electrically powered x-ray source and battery power for supplying electrical power to the x-ray source.

Abstract: Accordingly, the present invention provides an x-ray tomography apparatus having a patient table, x-ray tomography components located around the patient table and in an imaginary plane which intersects the table, and structure for supporting the table and tomography components and including apparatus for moving the tomography components along at least a portion of the table. In an alternate embodiment, an x-ray tomography apparatus includes an annular x-ray tomography system for continuously rotating around a patient, which structure has an electrically powered x-ray source and battery power for supplying electrical power to the x-ray source.