摘要:
A peripheral equalization (PE) method and apparatus for compensating for thickness reduction in outer edges of the breast in a mammogram (i.e. a two-dimensional image) while keeping the central area substantially unchanged. The PE method and apparatus can also be applied to three dimensional (tomosynthesis) images of a breast. The peripheral equalization is achieved by segmenting the image of the breast into at least two regions and using a multi-threshold technique to process the data in at least one of the two regions.
摘要:
An imaging method and apparatus is described in which distances between a source and an object are changed and projection images are generated at each of the different distances.
摘要:
An imaging method and apparatus is described in which distances between a source and an object are changed and projection images are generated at each of the different distances.
摘要:
A measurement system is presented. The measurement system includes a source and a detector located a selected distance from the source with the source and the detector movable about a point, an axis or about a plane located proximate the detector.
摘要:
A measurement system is presented. The measurement system includes a source and a detector located a selected distance from the source with the source and the detector movable about a point, an axis or about a plane located proximate the detector.
摘要:
The invention includes both systems and methods for tomosynthesis x-ray imaging. An x-ray source is moved at various positions in an arc around an object, e.g., a breast, to illuminate a stationary digital detector (or its equivalent) placed at an image plane behind the object. A digital image data processor collects data from the detector and a motion controller moves the source around the object. As the source moves along the arc, the detector generates, for a succession of points along the arc, a corresponding succession of image data sets, each set being representative of the intensity of x-rays incident on the detector for the then current position of the source. The image data processor is responsive to the image data sets to generate an output image signal representative of the x-ray absorption of points within the object region. The processor transforms the image plane data to a form corresponding to that which would have been generated had the x-ray source moved in a linear motion in a source plane parallel to the image plane, rather than an arc. The resultant image data thus corresponds in form to that produced by a conventional linear motion, e.g., Twinning-type, system, so that conventional techniques and equipment may be used to produce a final representation of the x-ray absorption of the object region.
摘要:
A system for three-dimensional tomosynthesis imaging of a target element includes an image acquisition element and a processor. The image acquisition element obtains a plurality of images of the target element from a plurality of angles and includes a radiation source that is positionable at a plurality of angles with respect to the target element and a radiation detector. The radiation detector is positioned so as to detect radiation emitted by the radiation source passing through the target element and determine a plurality of attenuation values for radiation passing through the target element to establish a radiation absorbance projection image of the target element for a particular radiation source angle. The processor is configured to apply an iterative reconstruction algorithm to the radiation absorbance projection images of the target element obtained from a plurality of radiation source angles to generate a three-dimensional reconstruction of the target element.
摘要:
Disclosed is a breast compression assembly for an mammography apparatus and a breast compression plate for use in such apparatus. The assembly includes a first compression plate having a first compression surface extending from an input edge thereof and a second compression plate having a second compression surface extending from an input edge thereof. At least one of the compression plates includes an associated ridge member affixed to its input edge. The ridge member extends beyond the surface of the associated compression plate in the direction substantially perpendicular to the compression surface of the plate. The device further includes means for positioning the first and second compression plates, and means for selectively controlling the separation between the compression surfaces of the plates along a reference axis substantially perpendicular to the compression surfaces of the plates.
摘要:
A system for three-dimensional tomosynthesis imaging of a target element is provided having an image acquisition element and a processor. The image acquisition element obtains a plurality of images of the target element from a plurality of angles and includes a radiation source that is positionable at a plurality of angles with respect to the target element and a radiation detector. The radiation detector is positioned so as to detect radiation emitted by the radiation source passing through the target element and determine a plurality of attenuation values for radiation passing through the target element to establish a radiation absorbance projection image of the target element for a particular radiation source angle. The processor is configured to apply an iterative reconstruction algorithm to the radiation absorbance projection images of the target element obtained from a plurality of radiation source angles to generate a three-dimensional reconstruction of the target element. The system can gain further accuracy where the iterative reconstruction algorithm is applied using cone-beam forward projection and back projection.
摘要:
A method for locating a lesion within a tissue mass, includes steps of measuring a selected parameter at two or more points in at least one path through the tissue mass, the measure of the selected parameter in a lesion being different from that in normal tissue. Also, apparatus for measuring a tissue parameter at two or more points in at least one path through the tissue mass includes an insertion needle, distally sharpened and made sufficiently rigid so that it can be inserted distal end foremost into the tissue mass along the path, and, insertible with the needle, a sensor capable of prodding a measure of the tissue parameter at a point in the tissue mass along the path. Where the parameter is selected as one that has a measure different in a lesion type, the apparatus can be used in carrying out the method, whereby a measure at a point in the tissue mass of the selected tissue parameter provided by the sensor indicates that the point is within a lesion. In an embodiment for measuring interstitial fluid pressure in the tissue mass, the sensor includes a tube slidably engageable within the lumen of the insertion needle; the sensor tube is closed at a distal end, and the walls of the sensor tube and the insertion needle are prodded distally with ports, positioned in relation to the respective distal ends such that when the sensor tube is engaged within the insertion tube lumen the ports can be substantially aligned to provide fluid communication between the lumen of the sensor tube and the tissue adjacent the ports; the sensor tube lumen contains a plurality of filaments, and is operationally connected to a pressure measurement deuce such that the pressure measurement deuce is responsive to fluid pressure within the sensor tube lumen.