323 results about "Contrast imaging" patented technology

Tissue contrast imaging systems are described which detect differences in tissue contrasts to obtain images of the tissue region. The systems may be used to obtain images of the cardiac tissues particularly in a blood-filled environment.

A radiographic phase-contrast imaging apparatus obtains a phase-contrast image using two gratings including the first grating and the second grating. The first and second gratings are adapted to form a moire pattern when a periodic pattern image formed by the first grating is superimposed on the second grating. Based on the moire pattern detected by the radiographic image detector, image signals of the fringe images, which correspond to pixel groups located at different positions with respect to a predetermined direction, are obtained by obtaining image signals of pixels of each pixel group, which includes pixels arranged at predetermined intervals in the predetermined direction, as the image signal of each fringe image, where the predetermined direction is a direction parallel to or intersecting a period direction of the moire pattern other than a direction orthogonal to the period direction. Then, a phase-contrast image is generated based on the obtained fringe images.

The invention relates to a visualized grouting test device and a visualized grouting test method of a fractured rock mass. Due to the arrangement of a CT (Computerized Tomography) scanning device, a whole-course visualized grouting test on a true fractured rock mass can be realized; by adding a specific proportion of barium sulfate into cement slurry, the problem of contrast imaging of grouting slurry in the true fractured rock mass under CT scanning is solved; a test box and a grouting anchor rod are made of transparent materials, thereby further improving the accuracy of a scanning result; the test box is set to be of an inner cavity size-adjustable structure, test pieces with different sizes can be tested, and the influence of grouting pressure size on a movement diffusion rule of the slurry in a rock mass fracture is obtained by comparing visualized grouting test results of all groups of test pieces under the same grouting time; by remotely controlling the starting and stopping of a CT machine and the opening and closing of a grouting valve through an integrated control panel, non-intermittent matching between test piece grouting and CT scanning is realized, the influence on slurry diffusion caused by CT scanning intervals is reduced to the greatest extent, and the whole grouting test process can be visualized.

Embodiments of methods and apparatus are disclosed for obtaining differential phase contrast imaging system and methods for same. Method and apparatus embodiments can provide regularized phase contrast retrieval that can address noise reduction and / or edge enhancement. Certain exemplary embodiments can suppress stripe artifacts occurring in the process of integration of noisy differential phase data. Further, certain exemplary embodiments can use transmission images and / or dark-field images to improve or restore phase contrast images affected by noise edges.

X-ray devices for Phase Contrast Imaging (PCI) are often built up with the help of gratings. For large field-of-views (FOV), production cost and complexity of these gratings could increase significantly as they need to have a focused geometry. Instead of a pure PCI with a large FOV, this invention suggests to combine a traditional absorption X-ray-imaging system with large-FOV with an insertable low-cost PCI system with small-FOV, The invention supports the user to direct the PCI system with reduced FOV to a region that he regards as most interesting for performing a PCI scan thus eliminating X-ray dose exposure for scanning regions not interesting for a radiologist. The PCI scan may be generated on the basis of local tomography.

An achromatic phase-contrast imaging apparatus for examining an object of interest is provided which comprises two different phase gratings which have different pitches. Thus, the imaging apparatus yields phase-contrast information for two different energies. Thus, phase-information over a wider energy band can be used.

Provided are signal modifying compositions for medical imaging comprising a carrier and two or more signal modifying agents specific for two or more imaging modalities. The compositions are characterized by retention efficiency, with respect to the signal modifying agents, which enables prolonged contrast imaging without significant depletion of the signal modifying agents from the carrier. The carriers of the present invention are lipid based or polymer based, the physico-chemical properties of which can be modified to entrap or chelate different signal modifying agents and mixtures thereof and to target specific organs or tumors or tissues within a mammal.

The present invention relates to differential phase-contrast imaging, in particular to a structure of a diffraction grating, e.g. an analyzer grating and a phase grating, for X-ray differential phase-contrast imaging. In order to make better use of the X-ray radiation passing the object, a diffraction grating (14) for X-ray differential phase-contrast imaging is provided with at least one portion (24) of a first sub-area (26) and at least one portion (28) of a second sub-area (30). The first sub-area comprises a grating structure (54) with a plurality of bars (34) and gaps (36) being arranged periodically with a first grating pitch P G (38), wherein the bars are arranged such that thy change the phase and / or amplitude of an X-ray radiation and wherein the gaps are X-ray transparent. The second sub-area is X-ray transparent and wherein the at least one portion of the second sub-area provides an X-ray 1 transparent aperture (40) in the grating. Portions of the first and second sub-areas are arranged in an alternating manner in at least one direction (42).

An X-ray radiography system for differential phase contrast imaging of an object under investigation by phase-stepping is provided. The X-ray radiography has an X-ray emitter for generating a beam path of quasi-coherent X-ray radiation, an X-ray image detector with pixels arranged in a matrix, and a diffraction or phase grating, in which the X-ray emitter has an X-ray tube with a cathode and an anode. The X-ray tube is constructed in such a way that an electron ray beam originating from the cathode is associated with focusing electronics which produce, from electrons which are incident on an anode, at least one linear-shaped electron fan beam.

The invention relates to a system and a method for X-ray grating contrast imaging. The system comprises an X-ray launching device, a first absorption grating, a second absorption, a detecting unit, a data processing unit and an imaging unit, wherein the X-ray launching device is used for launching X-ray beams to a detected article; the first absorption grating and the second absorption grating are positioned in the launching direction of the X-ray beams, and the X-ray refracted by the detected article forms X-ray signals with different intensity by the first absorption grating and the second absorption grating; the detecting unit is used for receiving the X-ray signals with changeable intensity and converting the X-ray signals into electric signals; and the data processing unit is used for processing and extracting the refraction angle information in the electric signals and calculating the pixel information through the refraction angle information; the imaging unit is used for constructing the image of the article. In addition, a rotating structure can also be utilized to rotate the article to realize a CT imaging mode so as to obtain refraction angles in a plurality of projection directions and the corresponding images and calculate the refraction index tomography image of the detected article by CT reconstruction algorithm. The system and the method adopt the common X-ray machine and the grating above a period of ten micron magnitude to realize the contrast imaging of a decimeter magnitude like viewing field.