Abstract: A method of calibration for reconstructing three-dimensional models from images obtained by a tomography apparatus comprising a radiation detector and an X-ray source which can move with respect to the detector. In the method a set of markers are placed in the field of the X-rays and the positions of the projections of the markers onto the images acquired are processed so as to deduce from this the position of the source at the time of acquisitions, the markers being carried by one and the same support. The markers are fixed with respect to the support and the positions of the projections of the markers onto the images acquired are processed so as to deduce from this the position of the markers in space.

Abstract: A method of compensation for the thickness of an organ in an X-ray machine of the type comprising an X-ray source and a detector of the beam of X-rays after it has passed through the organ, the detector being capable of converting the X-ray beam into a digital electronic signal, in which, from a digitized image, an image of the radiologic thicknesses of an organ traversed by the X-ray beam is calculated, a thickness threshold is defined, from this there is derived an algebraic compensation image to bring the pixels of a level below or above the threshold back to the value of the threshold, and the thickness image and a proportion of the compensation image are summed up, to obtain a compensated thickness image.

Abstract: A method of compensation for the thickness of an organ in an X-ray machine of the type comprising an X-ray source and a means of detection of the beam of X-rays after it has passed through the said organ, the detection means being capable of converting the X-ray beam into a digital electronic signal, in which, from a digitized image, an image of the radiologic thicknesses of an organ traversed by the X-ray beam is calculated, a thickness threshold is defined, from this there is derived an algebraic compensation image to bring the pixels of a level below or above the said threshold back to the value of the threshold, and the thickness image and a proportion of the compensation image are summed up, to obtain a compensated thickness image.

Abstract: Method of improved detection of elements of interest by means of a detection system in a digital radiographic image of an object, acquired on an acquisition chain, comprising a first calibration phase in which the performances of the detection system are established. For such purpose, a calibration curve with several dimensions is determined by means of a mathematical model of the acquisition chain and object, in order to express a false positive probability as a function of a set of parameters corresponding to the acquisition chain and object. In the course of a second phase of use, a false positive probability value is determined for each pixel of the image. One then selects among the pixels of the digital radiographic image acquired those whose probability value obtained satisfies a predetermined criterion.

Abstract: A mammography apparatus and method having an X-ray tube, an image receiver, the image receiver having one edge in contact with a patient, a compression paddle between the tube and the receiver, able to be moved up and down parallel to a direction of propagation of the X-rays, means for keeping the compression paddle in position in the radiation propagation direction, the compression paddle, in its compression position, being movable in at least one direction perpendicular to the direction of X-ray propagation and parallel to the contact edge of the image receiver. This allows a patient's breast to be rolled and presented to the image receiver in different positions thereby reducing ambiguities in possible detection of a lesion due to layers of tissue overlapping when images are taken.

Abstract: Method and apparatus and computer programs and computer medium for improving quality of a radiographic image of an object obtained by an X-ray apparatus containing an antidiffusion grid, placed between the object and a receiver of radiographic images, The grid is displaced in rectilinear translation in its plane on pickup of the image, between two positions according to a time displacement law which is a continuous curve with a time precision of approximately ±10% presenting at least five separate parts, the displacement taking place at constant speed over at least two parts and at variable speed over at least one part.

Abstract: A region of interest is selected in an input image, such as a digital or analog image form a mammography apparatus. Display parameters for the input image or a part thereof are determined as a function of the region of interest. The image or a part thereof is displayed using the determined parameters. Choosing display parameters as a function of the region of interest optimizes the display of the possible region of interest without any adjustment by the operator.

Abstract: Method and apparatus for a radiographic image of an object obtained by a radiography apparatus containing an X-ray emitter, in which an anti-scatter grid placed between the object and a radiographic image receiver is displaced, on rectilinear translation in its plane, when acquiring the images, between a starting position and an arrival position, according to a time displacement law of reference, at a greater rate of displacement in proximity to a starting position and to the arrival position. A measurement of the energy received in the form of X-radiation by the receiver is used to modify the rate of displacement of the grid at every instant.

Abstract: A method and apparatus for locating elements of a member from digital images taken at different angulations, in which elements present in a first digital image taken at a first angulation are determined. A deformation model of the member between the first angulation and another angulation is determined in order to deduce there from a search region in another digital image taken at the other angulation. Elements present are determined, in a search region of an element marked on the first image which has a high probability of being found. The image of the element is analyzed in order to assess their similarity.

Abstract: Method and apparatus for medical radiology and, in particular, galactography in the field of mammography. The method of obtaining radiological images in galactography comprises acquiring of a first radiological image of the breast in a compressed state: introducing a contrast medium in a part of the breast; acquiring at least a second radiological image of the breast in the compressed state and with contrast medium; and partial or complete subtraction of the first image in relation to the second image, or vice versa. An apparatus for use of the method comprises means for maintaining a breast compressed or immobilized and means for holding a catheter or the like for introducing a contrast medium in the breast.

Abstract: A method and device for sampling a fragment of tissue in which a contrast medium is injected into an organ to be examined and highlights parts containing that contrast medium in an image obtained by emitting a beam of X-rays. At least one pair of radiographic images is captured from a first position and a second position of an X-ray emitter during a phase of increasing attenuation due to the contrast medium. A specific area is identified from the pair of images in which a tissue fragment is to be sampled. The images of the pair of images are combined to determine the three-dimensional coordinates of the specific area.

Abstract: A method of calibration for reconstructing three-dimensional models from images obtained by a tomography apparatus comprising a radiation detector and an X-ray source which can move with respect to the detector. In the method a set of markers are placed in the field of the X-rays and the positions of the projections of the markers onto the images acquired are processed so as to deduce from this the position of the source at the time of acquisitions, the markers being carried by one and the same support. The markers are fixed with respect to the support and the positions of the projections of the markers onto the images acquired are processed so as to deduce from this the position of the markers in space.

Abstract: Method and apparatus and computer programs and computer medium for improving quality of a radiographic image of an object obtained by an X-ray apparatus containing an antidiffusion grid, placed between the object and a receiver of radiographic images, The grid is displaced in rectilinear translation in its plane on pickup of the image, between two positions according to a time displacement law which is a continuous curve with a time precision of approximately ±10% presenting at least five separate parts, the displacement taking place at constant speed over at least two parts and at variable speed over at least one part.

Abstract: Method and apparatus for medical radiology and, in particular, galactography in the field of mammography. The method of obtaining radiological images in galactography comprises acquiring of a first radiological image of the breast in a compressed state: introducing a contrast medium in a part of the breast; acquiring at least a second radiological image of the breast in the compressed state and with contrast medium; and partial or complete subtraction of the first image in relation to the second image, or vice versa. An apparatus for use of the method comprises means for maintaining a breast compressed or immobilized and means for holding a catheter or the like for introducing a contrast medium in the breast.

Abstract: Method and system for compensating for the thickness of an organ in a radiology instrument, in which an image of the radiological thicknesses of the organ through which the X-ray beam has passed is calculated on the basis of a digitized image, the thickness image is filtered using a low-pass filter in order to obtain a low-frequency image, the low-frequency image is subtracted from the radiological thickness image in order to obtain a contrast image, the low-frequency image is processed using a pre-recorded table taking into account a contract &khgr; selected by a user in order to obtain an image with reduced dynamic range, and the image with reduced dynamic range is added to the contrast image in order to obtain a compensated thickness image, the pixels having a level below or above a predetermined threshold being returned at least to the value of the threshold, while preserving the differences and real ratios between the anatomical structures.

Abstract: A vibrating rate gyro structure machined in a plate of material and comprising a fixed part, a resonator, and a mechanical system connecting the resonator to the fixed part. The mechanical system comprises a first mobile mass part connected to one end of the resonator, a second mobile mass part (4) connected to the resonator and situated in the vicinity of the other end of the resonator, two flexible arms situated on both sides of the resonator and each connecting the first mobile mass part to the second mobile mass part, and two other flexible arms situated on both sides of the resonator and connecting the second mobile mass part to the fixed part.

Abstract: A monolithic miniature accelerometer machined in a plate of material, comprising a fixed part, two first mobile mass parts referred to as inertial masses, two hinge blades each having one end fastened to one of the two mobile mass parts, and two resonators each having one end fastened to one of the two mobile mass parts, a third mobile mass part fastened to the other end of each of the two resonators and of each of the two hinge blades, and a flexible stem situated between the first two mobile mass parts and connecting the third mobile mass part to the fixed part.

Abstract: A vibrating rate gyro structure machined in a plate of material and comprising a fixed part, a resonator, and a mechanical system connecting the resonator to the fixed part. The mechanical system comprises a first mobile mass part connected to one end of the resonator, a second mobile mass part (4) connected to the resonator and situated in the vicinity of the other end of the resonator, two flexible arms situated on both sides of the resonator and each connecting the first mobile mass part to the second mobile mass part, and two other flexible arms situated on both sides of the resonator and connecting the second mobile mass part to the fixed part.

Abstract: Method and apparatus for examination of a breast, in which a contrast medium is injected in the breast to be examined, an X-ray beam is emitted in the direction of the breast; a plurality of digital images of the X-ray beam is taken after it has crossed the breast, and a representative image of the contrast produced in the tissues of the breast is calculated from the digital images.

Abstract: Radiological imaging device comprising an emitter of an X-ray beam and a receiver of the X-ray beam after it has crossed an organ, the organ being capable of being placed between the receiver and a compression element, capable of being removably fixed on the device. A calculation unit includes a means for optimizing the image quality over a particular area defined by the compression element.