133 results about "Digital subtraction angiography" patented technology

A method for eliminating motion artifacts in digital subtraction angiography comprises the following steps: step 1, reading; step 2, selecting points; step 3, constructing a DSA space body; step 4, carrying out space slicing; step 5, connecting tracks; step 6, analyzing the space motion characteristics of DSA pixel; step 7, carrying out triangulation; step 8, carrying out affine transformation; step 9, carrying out space winding; step 10, optimizing; step 11, registering; step 12, carrying out grey correction; step 13, carrying out logarithmic subtraction angiography. The invention belongs to the technology of image processing. The method of space analysis is used so that the registering of DSA image is more accurate, thereby efficiently eliminating motion artifacts and obtaining clear angiography images. Thus, the diagnostic accuracy of a doctor is improved, and the working efficiency is increased.

The invention provides an image stitching method and device. The image stitching method and device are used for stitching three-dimensional digital subtraction angiography images. The image stitching method comprises the steps of obtaining first volume data and second volume data, wherein the first volume data and the second volume data are volume data of overlapped areas, used for stitching, of every two adjacent angiography images; maximum intensity projection is conducted on both the first volume data and the second volume data, so that a first image corresponding to the first volume data and a second image corresponding to the second volume data are obtained; two-dimensional registration is conducted on the first image and the second image; according to a registration result, three-dimensional registration is conducted on the first volume data and the second volume data; image fusion is conducted on the overlapped areas, used for stitching, of every two adjacent angiography images after correction is conducted according to a three-dimensional registration result, and therefore stitching of the images is achieved. By the adoption of the image stitching method, the accuracy of a three-dimensional registration algorithm can be effectively improved, and the stitching time of the images can be effectively shortened.

An apparatus and methodological framework are provided, named perfusion angiography, for the quantitative analysis and visualization of blood flow parameters from DSA images. The parameters, including cerebral blood flow (CBF) and cerebral blood volume (CBV), mean transit time (MTT), time-to-peak (TTP), and T_max, are computed using a bolus tracking method based on the deconvolution of time-density curves on a pixel-by-pixel basis. Individual contrast concentration curves of overlapping vessels can be delineated with multivariate Gamma fitting. The extracted parameters are each transformed into parametric maps of the target that can be color coded with different colors to represent parameter values within a particular set range. Side by side parametric maps with corresponding DSA images allow expert evaluation and condition diagnosis.

The invention discloses an electrochemical reactor for processing nitrogenous organic wastewater, and an application and a processing method thereof, and belongs to the field of processing nitrogenous organic wastewater. The device comprises a reaction container, a power supply, a gas outlet pipe, a water outlet pipe, a water outlet pipe valve and a water inlet system, and further comprises a packing material, a negative plate and a positive plate, wherein the packing material is formed by mixing active carbon and magnet particles; the negative plate is connected with the negative electrode of the power supply; the negative plate is a silicon dioxide plate loaded copper-palladium coating electrode, and the coating material consists of Pd and Cu at a mass ratio of 6: 1; and the positive plate is a digital subtraction angiography (DSA) oxide coating electrode Ti/IrO2-PtO2. The reactor is a batch-type operation three-dimensional electrode reactor which adopts a mixture of active carbon particles and magnet particles with similar diameter as the packing material, and has the functions of efficiently removing nitrate nitrogen, ammonia nitrogen and COD (chemical oxygen demand), and is low in energy consumption; and the reactor is capable of achieving a purpose of removing nitrogen and COD in the nitrogenous organic wastewater.

The invention discloses a rapid registering and splicing method used for a three-dimensional digital subtraction angiography image. The method comprises the following steps: a) two volume data images of the three-dimensional digital subtraction angiography image are selected, and the overlapped areas are extracted to denote as sub-volume-data images; b) maximum intensity projection is performed on the sub-volume-data images at a coronal surface, a sagittal surface and a cross section respectively so that MIP1 and MIP2 images are formed; c) first time of registering is performed on the MIP1 and MIP2 images respectively at the aforementioned two-dimensional surfaces; d) and second time of registering is performed on the two volume data images in three-dimensional space according to the result of the first time of registering, then the overlapped areas are fused and finally a panoramic three-dimensional subtraction volume data image is formed via splicing. According to the rapid registering and splicing method used for the three-dimensional digital subtraction angiography image, influence of image data quality on registering precision can be avoided, and registering and splicing processing time can be greatly shortened.

A method and system for extracting motion-based layers from fluoroscopic image sequences are disclosed. Portions of multiple objects, such as anatomical structures, are detected in the fluoroscopic images. Motion of the objects is estimated between the images is the sequence of fluoroscopic images. The images in the fluoroscopic image sequence are then divided into layers based on the estimated motion. In a particular implementation, the coronary vessel tree and the diaphragm can be extracted in separate motion layers from coronary angiograph fluoroscopic image sequence.

A motion compensated digitally subtracted Angiography (DSA) image processing system includes an interface for acquiring a sequence of images of patient vessels both prior to and following introduction of contrast agent into the vessels. An image data processor automatically, (a) determines a first shift vector for a first image of the sequence for compensating for shift between the first image and a first reference image of the sequence, (b) applies the determined first shift vector to the first image of the sequence to produce a shifted image, (c) subtracts the first reference image from the shifted image to produce a subtracted image enhancing vessel structure, (d) determines a second shift vector for compensating for shift between the subtracted image and a second reference image and (e) shifts content of the subtracted image relative to the second reference image in response to the second shift vector, to provide a shifted subtracted image enhancing and aligning vessel structure.

The invention discloses a U-net based generation adversarial network based digital substration angiography DSA imaging method and device. The method comprises the following steps: firstly, obtaining aplurality of groups of radiography frames and original data corresponding to the subtraction frames; secondly, establishing a U-shaped structure convolutional network, coding and extracting featuresof different scales, and decoding and recovering corresponding features by using a skill connected object, wherein the network inputs a radiography frame and outputs a corresponding subtraction frameto reduce the dependence of DSA generation on a background frame so as to remove motion artifacts generated by motion of a patient; then, by means of generative adversarial training, alternately training the generator and the discriminator, and enhancing the quality of generated digital blood vessel subtraction. According to the method, the motion artifacts in the digital substration angiography (DSA) can be effectively removed, the data quality can meet the requirements of clinical analysis, diagnosis and the like, the DSA imaging quality is improved, and the influence caused by motion of a patient is reduced.

An X-ray diagnostic imaging system for generating images in digital subtraction angiography is proposed. A mask image frame of a patient and a series of live image frames of the patient acquired in the same imaging position of the mask frame acquisition are accessed. One of the mask and the live image frames is contrast-enhanced. Possible shift vectors in a region of interest are assumed being a difference vector between the mask and a respective live image frame and a scoring is calculated. Possible shift vector with the highest scoring is chosen as an elected shift vector. A likelihood representing a quality value of the elected shift vector is calculated. The mask image frame is shifted with respect to the respective live image frame by a modified shift vector depending on the likelihood. The shifted mask image frame is subtracted from the respective live image frame and is displayed.

The invention discloses a method for segmenting a blood vessel in a digital subtraction angiography (DSA) image sequence. The method comprises the following steps of: removing noise from a background, performing background separation on an angiography sequence image by a fuzzy C-mean clustering algorithm, and extracting the blood vessel of the angiography sequence image in the angiography image sequence by a background difference method. The method can be used for effectively segmenting the angiography sequence, and is simple in operation and high in segmenting efficiency.

An image processing method and related system to register projection images (AG, MI) only with respect to a motion of a landmark across said images. The motion of the landmark relates to a motion of a region of interest, ROI. The so registered images (AG, MI) are then subtracted from each other to arrive at a difference image that is locally motion compensated and that represents the ROI at good contrast whilst subtraction artifacts can be avoided.

A method and system for evaluating image segmentation is disclosed. In order to quantitatively evaluate an image segmentation technique, synthetic image data is generated and the synthetic image data is segmented to extract an object using the segmentation technique. This segmentation results in a foreground containing the extracted object and a background. The visibility of the extracted object is quantitatively measured based on the intensity distributions of the segmented foreground and background. The visibility is quantitatively measured by calculating the Jeffries-Matusita distance between the foreground and background intensity distributions. This method can be used to evaluate segmentation of vessels in fluoroscopic image sequences by coronary digital subtraction angiography (DSA).

The invention relates to the field of digital processing of x-ray images and can be used in digital subtraction angiography to compensate for impact of involuntary patient movement and movement of internal organs on image of the vascular system. The technical result of the claimed invention is the improvement of diagnostic value of subtraction angiographic images by eliminating artifacts caused by the motility of anatomical structures. Technical result is achieved by the that at the stage of digital images registration a search for characteristic details is performed for each image. According to the shift of the said details determine expectable shift of a patient organs. Then perform segmentation of image from the pre-contrast series in the region of homogenous warping; for each region a geometrical transformation is calculated and corresponding geometrical transformations are performed for each region of a series of pre-contrast digital images.

The invention provides an integrated intravascular OCT (optical coherence tomography) image and DSA (digital subtraction angiography) integrating offline treatment system, which comprises a data acquisition module, a DSA-image-based blood vessel segmentation and reconstruction module, an OCT-image-based blood vessel measurement module, a blood vessel three-dimensional imaging module, a DSA image and OCT image linkage module, an image reporting module and a transmission module. According to the system, a blood vessel is multidimensionally treated by combining a DSA image and an OCT image to further facilitate the accurate positioning of an interested blood vessel section; a blood vessel measurement result obtained by the DSA-image-based blood vessel segmentation and reconstruction module is compared with a blood vessel measurement result, obtained by the OCT-image-based blood vessel measurement module, on a cross section, so that the blood vessel treatment research accuracy of a doctor or a researcher after an operation is improved to facilitate the supply of a more perfect therapeutic schedule for an interventional operation in a similar case in the future.

The invention relates to a medical image processing method which is characterized in that images formed by three-dimensional fast spin echo imaging collected by a magnetic resonance imaging system in the focus area of a patient and blood vessel images collected by a digital subtraction angiography machine are subjected to reconstruction, color inverting, cutting, 3D-3D fusion and 3D-2D registering through a post-processing work station of the digital subtraction angiography machine, so that three-dimensional blood vessel graphs can be overlapped on a real-time radio-fluoroscopic image. Therefore, by adopting the medical image processing method, real-time imaging guide can be performed during nerve involvement surgeries for blocked blood vessels, the near end and far end of the closed section of the blood vessel can be shown simultaneously through imaging, and physicians can clearly get known of conditions in the focus areas and further can perform operating better.

A method and system for extracting coronary vessels fluoroscopic image sequences using coronary digital subtraction angiography (DSA) are disclosed. A set of mask images of a coronary region is received, and a sequence of contrast images for the coronary region is received. For each contrast image, a motion estimate is calculated between each of the mask images and a background region of the contrast image and a covariance is calculated for each motion estimate. Multiple background layer predictions are generated by generating a background layer prediction for each mask image based on the calculated motion estimate and covariance. The multiple background layer estimates are combined using statistical fusion to generate a final estimated background layer. The final estimated background layer is subtracted from the contrast image to extract a coronary vessel layer for the contrast image.

The invention discloses an intracranial aneurysm 3D (three-dimensional) model printing method based on DSA (digital subtraction angiography) data. The method includes the steps: acquiring original DSA image data and outputting the image date; leading the outputted image date into a medicine 3D model reconstruction system to reconstruct cerebral vascular data; automatically extracting the DSA cerebral vascular data by the 3D model reconstruction system; selecting needed DSA cerebral vascular data model to build a 3D model; trimming the obtained model; printing a cerebral vascular and intracranial aneurysm model by the aid of a 3D printer. The intracranial aneurysm 3D model is more refined and more suitable for an entity model, has a smoother surface and can display tiny branch vessels and provide more important reference for operations.