Abstract: A method for determining a beam width of a computed tomography scanner includes calculating a dose length product DLP and dividing it by an accumulated radiation dose D(0). In some embodiments, DLP is calculated from measurements obtained using a pencil ionization chamber and a radiopaque mask that is slid over the chamber. In other embodiments, DLP is calculated from measurements obtained using a radiation dosimeter that is moved long a longitudinal axis of the scanner at a known velocity v.

Abstract: The present disclosure provides a bi-directional image receptor assembly capable of receiving an image receptor in either a lengthways (or longitudinal) or crossways (or transverse) orientation, while maintaining the axis of an anti-scatter grid in a fixed position. The axis of the anti-scatter grid can be placed in a fixed orientation (such as a parallel orientation) to a subject's craniocaudal axis regardless of whether the image receptor is inserted in the lengthways or crossways orientation. Methods of using the bi-directional image receptor assembly in mobile radiography are also disclosed. The present disclosure further provides for an X-ray image receptor comprising a portion of an automatic position measurement system. Still further, the present disclosure provides for a cover comprising a reinforcing geometry that maximizes the strength of the cover while minimizing the thickness of the cover.

Abstract: The present disclosure provides a bi-directional image receptor assembly capable of receiving an image receptor in either a lengthways (or longitudinal) or crossways (or transverse) orientation, while maintaining the axis of an anti-scatter grid in a fixed position. The axis of the anti-scatter grid can be placed in a fixed orientation (such as a parallel orientation) to a subject's craniocaudal axis regardless of whether the image receptor is inserted in the lengthways or crossways orientation. Methods of using the bi-directional image receptor assembly in mobile radiography are also disclosed. The present disclosure further provides for an X-ray image receptor comprising a portion of an automatic position measurement system. Still further, the present disclosure provides for a cover comprising a reinforcing geometry that maximizes the strength of the cover while minimizing the thickness of the cover.

Abstract: The present disclosure provides a bi-directional image receptor assembly capable of receiving an image receptor in either a lengthways (or longitudinal) or crossways (or transverse) orientation, while maintaining the axis of an anti-scatter grid in a fixed position. The axis of the anti-scatter grid can be placed in a fixed orientation (such as a parallel orientation) to a subject's craniocaudal axis regardless of whether the image receptor is inserted in the lengthways or crossways orientation. Methods of using the bi-directional image receptor assembly in mobile radiography are also disclosed. The present disclosure further provides for an X-ray image receptor comprising a portion of an automatic position measurement system. Still further, the present disclosure provides for a cover comprising a reinforcing geometry that maximizes the strength of the cover while minimizing the thickness of the cover.

Abstract: Disclosed is a mobile radiographic unit with improved x-ray scatter control. Improved x-ray scatter control is provided through the alignment of the system with the focal line of an anti-scatter grid. In a preferred embodiment, the system comprises an x-ray source assembly, a tube housing mounting, a measuring system, a motion control system and a processor in communication with the measuring system and the motion control system.

Abstract: Disclosed is a mobile radiographic unit with improved x-ray scatter control. Improved x-ray scatter control is provided through the alignment of the system with the focal line of an anti-scatter grid. In a preferred embodiment, the system comprises an x-ray source assembly, a tube housing mounting, a measuring system, a motion control system and a processor in communication with the measuring system and the motion control system.

Abstract: Disclosed is an X-ray imaging system that comprises a high ratio, high primary transmission anti-scatter grid in combination with a dynamic X-ray tube output function to eliminate or reduce gridline artifacts. Conventional X-ray imaging systems utilizing conventional anti-scatter grids generally require that the grid be moved a distance of at least 20 grid pitches to eliminate gridline artifacts. Through the use of the anti-scatter grid and dynamic output function described, such artifacts are eliminated or substantially reduced when the grid travels a short distance. Any function that has zero frequency components at positive integer multiples of the reciprocal of the grid repeat time will completely suppress gridline artifacts. Any function that is equal to the convolution of an arbitrary function with a rect function whose width is a positive multiple of the grid repeat time will fit this criterion, and its use will completely suppress gridline artifacts.

Abstract: Disclosed is a mobile radiographic unit with improved x-ray scatter control. Improved x-ray scatter control is provided through the alignment of the system with the focal line of an anti-scatter grid. In a preferred embodiment, the system comprises an x-ray source assembly, a tube housing mounting, an automatic measuring means, a motion control means and a processing means in communication with the automatic measuring system and the motion control system. The alignment of the system occurs with minimal input by the operator.

Abstract: Disclosed is an X-ray imaging system that comprises a high ratio, high primary transmission anti-scatter grid in combination with a dynamic X-ray tube output function to eliminate or reduce gridline artifacts. Conventional X-ray imaging systems utilizing conventional anti-scatter grids generally require that the grid be moved a distance of at least 20 grid pitches to eliminate gridline artifacts. Through the use of the anti-scatter grid and dynamic output function described, such artifacts are eliminated or substantially reduced when the grid travels a short distance. Any function that has zero frequency components at positive integer multiples of the reciprocal of the grid repeat time will completely suppress gridline artifacts. Any function that is equal to the convolution of an arbitrary function with a rect function whose width is a positive multiple of the grid repeat time will fit this criterion, and its use will completely suppress gridline artifacts.

Abstract: Disclosed is a mobile radiographic unit with improved x-ray scatter control. Improved x-ray scatter control is provided through the alignment of the system with the focal line of an anti-scatter grid. In a preferred embodiment, the system comprises an x-ray source assembly, a tube housing mounting, an automatic measuring means, a motion control means and a processing means in communication with the automatic measuring system and the motion control system. The alignment of the system occurs with minimal input by the operator.

Abstract: A scanning radiographic system having reduced scatter and improved tube loading employs a pre-patient slit to form the x-ray beam into a fan beam and a post-patient slot to eliminate scattered rays from the fan beam. A grid incorporated into the slot permits a further reduction of scatter sufficient to employ a wider slot without detrimental increase in scatter but with significant improvement in tube loading. The lamellae of the grid proceed diagonally across the width of the slot to reduce grid lines and are tipped to focus on the focal spot of the x-ray source.

Abstract: An energy discriminating apparatus and method is disclosed for use in connection with digital radiography and fluoroscopy. In use of the detection system and method an x-ray source is actuated to direct x-rays through a patient's body, the x-rays including both higher and lower energy radiation. A first detector element, including a plurality of segments, is positioned opposite the source to receive and respond predominantly to x-rays in a lower energy range, the remaining x-rays, being generally of higher energy, passing through the first detector element. A second detector element, also including a plurality of segments, each segment including a phosphor coating layer and a sensor, is positioned to receive and respond to the higher energy radiation passing through the first element.

Abstract: A system and method is disclosed for utilizing image pixel value information generated by a digital radiographic system for quantifying the amount of calcium in a particular object of interest within a subject, wherein the subject also contains additional quantities of calcium located at positions such that the additional calcium interfers with the acquisition of data describing the object of interest. A cursor configured as a parallelogram is described and pixel values are summed along lines parallel to the sides of the parallelogram. A profile is generated from these summations. A portion of the profile corresponding to pixel lines not intersecting the object of interest is used to estimate the contribution of background and other calcium to the profile as a whole, and this estimated value is subtracted from the total profile. Integration of the remainder of the profile provides a scalar value corresponding to the amount of calcium in the object of interest.

Abstract: An energy discriminating apparatus and method is disclosed for use in connection with digital radiography and fluoroscopy. In use of the detection system and method an x-ray source is actuated to direct x-rays through a patient's body, the x-rays including both higher and lower energy radiation. A first detector element, including a plurality of segments, is positioned opposite the source to receive and respond predominantly to x-rays in a lower energy range, the remaining x-rays, being generally of higher energy, passing through the first detector element. A second detector element, also including a plurality of segments, each segment including a phosphor coating layer and a sensor, is positioned to receive and respond to the higher energy radiation passing through the first element.

Abstract: A scanning grid apparatus exhibiting high primary and low secondary X-Ray transmission of X-Ray radiation emitted from an X-Ray source defining a focal spot, including at least one scanning grid provided with top and bottom pairs of opposed grid slat retainers disposed in parallel planes. Pivotably attached between the top pair of retainers is a plurality of radiopaque linear or wavy grid slats separated at predetermined distances in the plane of the top pair of retainers. The bottom pair of retainers includes spacers for maintaining the grid slats separated predetermined distances within allowable limits in the plane of the bottom pair of retainers. The separation distances provided by the bottom pair of retainers is chosen as the geometric projection of the separation distances in the plane of the top pair of retainers from the source focal spot to the plane of the bottom pair of retainers, such that each of the grid slats is focused on the focal spot of the X-Ray source.

Abstract: A multiple beam computed tomography (CT) scanner formed of plural interspaced groups of small, densely packed radiation detectors provided in a stationary ring around a body. The ring defines the cross-sectional slice of the body which is scanned by moving an X-ray source in a circle having a smaller radius and the same plane and center as that of the detector ring. A rotatably mounted collimator having a plurality of beam defining apertures is positioned between the X-ray source and patient. The collimator defines a plurality of fan-shaped X-ray beams that strike the detectors after passing through the patient and eliminates radiation from impinging on the patient that would pass through and strike the dead spaces between detector groups. The X-ray source and collimator rotate synchronously maintaining the registration between any given X-ray beam and detector group while the area of interest for the given detector group is scanned by the X-ray beam.

Abstract: A method and apparatus are disclosed for reducing scatter in diagnostic radiology and thereby improving image clarity and resolution, particularly in mammography or where abdominal organs are being studied. The method includes the use of a scanning multiple slit arrangement in conjunction with a conventional X-ray generator and imaging modality. A first or upper plate having a plurality of slits is placed between the patient to be X-rayed and the focal spot of an X-ray tube. A second or lower plate having corresponding number of slits, but substantially expanded in scale relative to the first plate, is placed beneath the patient but above the photographic cassette on which the X-ray image is to be recorded. The lower plate may consist of a bifurcated plate structure or a single, thick, slotted plate. The upper and lower slit structures are coupled together and are mechanically driven by a suitable drive mechanism to rapidly scan the patient with a group of separate beams produced by the upper slit plate.

Abstract: An energy discriminating apparatus and method is disclosed for use in connection with digital radiography and fluoroscopy. In use of the detection system and method an x-ray source is actuated to direct x-rays through a patient's body, the x-rays including both higher and lower energy radiation. A first detector element, including a plurality of segments, is positioned opposite the source to receive and respond predominantly to x-rays in a lower energy range, the remaining x-rays, being generally of higher energy, passing through the first detector element. A second detector element, also including a plurality of segments, each segment including a phosphor coating layer and a sensor, is positioned to receive and respond to the higher energy radiation passing through the first element.