226 results about "Helical computed tomography" patented technology

A method and an arrangement are provided for scalable confocal interferometry for distance measurement, for 3-D detection of an object, for OC tomography with an object imaging interferometer and at least one light source. The interferometer has an optical path difference not equal to zero at each optically detected object element. Thus, the maxima of a sinusoidal frequency wavelet, associated with each detected object element, each have a frequency difference Δf_Objekt. At least one spectrally integrally detecting, rastered detector is arranged to record the object. The light source preferably has a frequency comb, and the frequency comb differences Δf_Quelle are changed in a predefined manner over time in a scan during measuring. In the process, the frequency differences Δf_Quelle are made equal to the frequency difference Δf_Objekt or equal to an integer multiple of the frequency differences Δf_Objekt at least once for each object element.

Provided herein are the systems, methods, components for a three-dimensional tomography system. The system is a dual-modality imaging system incorporates a laser ultrasonic system and a laser optoacoustic system. The dual-modality imaging system has means for generate tomographic images of a volume of interest in a subject body based on speed of sound, ultrasound attenuation and/or ultrasound backscattering and for generating optoacoustic tomographic images of distribution of the optical absorption coefficient in the subject body based on absorbed optical energy density or various quantitative parameters derivable therefrom. Also provided is a method for increasing contrast, resolution and accuracy of quantitative information obtained within a subject utilizing the dual-modality imaging system. The method comprises producing an image of an outline boundary of a volume of interest and generating spatially or temporally coregistered images based on speed of sound and/or ultrasonic attenuation and on absorbed optical energy within the outlined volume.

The present invention generally refers to a correction method for grating-based X-ray differential phase contrast imaging (DPCI) as well as to an apparatus which can advantageously be applied in X-ray radiography and tomography for hard X-ray DPCI of a sample object or an anatomical region of interest to be scanned. More precisely, the proposed invention provides a suitable approach that helps to enhance the image quality of an acquired X-ray image which is affected by phase wrapping, e.g. in the resulting Moiré interference pattern of an emitted X-ray beam in the detector plane of a Talbot-Lau type interferometer after diffracting said X-ray beam at a phase-shifting beam splitter grating. This problem, which is further aggravated by noise in the obtained DPCI images, occurs if the phase between two adjacent pixels in the detected X-ray image varies by more than π radians and is effected by a line integration over the object's local phase gradient, which induces a phase offset error of π radians that leads to prominent line artifacts parallel to the direction of said line integration.

A Nuclear Medicine (NM) imaging system and method using multiple types of imaging detectors are provided. One NM imaging system includes a gantry, at least a first imaging detector coupled to the gantry, wherein the first imaging detector is a non-moving detector, and at least a second imaging detector coupled to the gantry, wherein the second imaging detector is a moving detector. The first imaging detector is larger than the second imaging detector and the first and second imaging detectors have different detector configurations. The NM imaging system further includes a controller configured to control the operation of the first and second imaging detectors during an imaging scan of an object to acquire Single Photon Emission Computed Tomography (SPECT) image information such that at least the first imaging detector remains stationary with respect to the gantry during image acquisition.

A method for reconstructing image component densities of an object includes acquiring multi-spectral x-ray tomographic data, performing a material decomposition of the multi-spectral x-ray tomographic data to generate a plurality of material sinograms, and reconstructing a plurality of material component density images by iteratively optimizing a functional that includes a joint likelihood term of at least two of the material decomposed sinograms. An x-ray tomography imaging system and a non-transitory computer readable medium are also described herein.

A method, system, and computer program product for compensating for the unavailability of projection data of a scanned object at a selected point, the selected point located outside a detection range of a detector. The method include the steps of obtaining projection data of the scanned object, and compensating for the unavailability of the projection data at the selected point based on the obtained projection data and coordinates of the selected point relative to the detector. The compensating step includes determining at least one complementary projection angle and coordinates of at least one complementary point based on a source projection angle and the coordinates of the selected point relative to the detector, and estimating the projection data value at the selected point based on the acquired projection data, the at least one complementary projection angle, and the coordinates of the at least one complementary point.

The invention comprises a system for controlling a charged particle beam shape and direction relative to a controlled and dynamically positioned patient and/or an imaging surface, such as a scintillation plate of a tomography system and/or a first two-dimensional imaging system coupled to a second two-dimensional imaging system. Multiple interlinked beam/patient/imaging control stations allow safe zone operation and clear interaction with the charged particle beam system and the patient. Both treatment and imaging are facilitated using automated sequences controlled with a work-flow control system.

Ultrasonograms (105, 106) are created by means of ultrasonic probe (104). Volume image data is created previously by using an image diagnosis apparatus (102) and stored in a volume data storage unit (107). From the stored volume image data, a tomogram corresponding to the scan surface of the ultrasonic images is extracted, and a reference image (111) is formed from the tomogram. The ultrasonograms and the reference image are displayed on the same screen (114). An area of the reference image corresponding to the viewing area of the ultrasonogram is extracted, and a reference image of the same portion as that of the ultrasonic image is displayed as a fan image and/or displayed with the same magnification as that of the ultrasonograms.

Disclosed is a Computer Tomography (CT) system including a gantry having first and second semicircular support elements which are concentric with one another. Each of the first and second semicircular support elements has a missing sector and at least one of the missing sectors may be of an angle of 180 degrees or less. A controller may be adapted to regulate relative rotational positions between said first and second support elements.

An x-ray radiography tomography device for a flexible riser, particularly a riser end fitting on a riser hangoff block on a petroleum platform, the x-ray radiography device comprising the following features: a) an x-ray source (1) of about 6 to 9 MeV arranged for directing said x-rays generally through an adjacent and an opposite sidewall portion of said riser; b) a collimator (2) arranged between said x-ray source (1) and said sidewall of said riser pipe being adjacent to said source (1), said collimator (2) arranged for directing radiation said x-rays in a beam fan generally extending in a plane perpendicular to a long axis of the riser; c) a sensor array (3) for receiving said x-ray beam fan after passage throug said riser pipe, said array comprising a plurality of scintillation detectors (30), said sensor array (3) arranged generally opposite of said source (1) with respect to said riser tube, and extending along a line extending generally perpendicular to said axis of said riser; d) an internal frame (7) for rotating the x-ray source (1), the collimator (2) and the sensor array (3) generally about said axis of said riser, said framework arranged on a circular guide rail (10) mounted around said flexible riser hangoff block.

When calibrating a positron emission tomography (PET) scanner, a radioactive calibration phantom is scanned over a period of several half lives to acquire a plurality of frames of scan data. Interlaced timing windows are employed to facilitate acquiring coincidence data for a plurality of coincidence timing windows and energy windows during a single calibration scan. Coincident events are binned according to each of a plurality of selected coincidence windows, and the PET scanner is calibrated for each of the plurality of coincidence timing windows using data acquired from the single calibration scan.

A system for optical tomography includes an apparent light source adapted to project excitation light toward a specimen having fluorescent proteins therein, wherein the excitation light enters the specimen becoming intrinsic light within the specimen, wherein the intrinsic light is adapted to excite fluorescent light from the fluorescent proteins, and wherein the intrinsic light and the fluorescent light are diffuse. A method of optical tomography includes generating the excitation light with the apparent light source, wherein the intrinsic light and the fluorescent light are diffuse.

The present application is directed toward the generation of three dimensional images in a tomography system having X-ray sources offset from detectors, in particular in a system where the sources are located on a plane, while detectors are located on multiple parallel planes, parallel to the plane of sources and all the planes of detectors lie on one side of the plane of sources. A controller operates to rebin detected X-rays onto a non-flat surface, perform two dimensional reconstruction on the surface, and generate the three dimensional image from reconstructed images on the plurality of surfaces.

An MR tomography apparatus has a system for contrast optimization of MRT images, with: an input unit for measurement parameters such as, for example, TR, TE, FOV, matrix size, flip angle, . . . etc. a unit for establishment of the anatomical area to be examined in the examination subject; a unit for combination of a plurality of MRT images acquired with various measurement parameters; and a unit for visualization and generation of a DICOM header for selected MRT image combinations. The tomography apparatus also has a storage unit in which predetermined experiential values for parameters of equations for combination of a number of various MRT images are stored with regard to a number of selectable anatomical areas of an examination subject; and an acquisition unit for generation of MRT images under selective consideration of the experiential values for measurement parameters that are stored for the anatomical structure to be examined.

Discrete tomographic apparatus comprises an electron microscope for irradiating a sample comprising an atomic lattice structure. Line count data is obtained for the main directions of a cross section of the sample. A non-linear programming algorithm is applied to obtain probabilities of occupancy of lattice sites by atoms of the sample. The non-linear programming algorithm comprises an iterative application of the expectation/maximization algorithm upper bounded by the constraint that each variable is valued at less than or equal to one. Once the algorithm is iteratively applied a phantom image of the cross section of the sample is generated. The cross sectional area may be less than one thousand atoms by one thousand atoms.