Abstract: A system acquires images in the presence of a contrast agent of relatively long persistence using a synchronization processor, image acquisition device and imaging controller. The synchronization processor provides an image acquisition trigger signal for acquiring images at a particular point within both a cardiac and a respiratory cycle in response to signals representing cardiac and respiratory cycles. The image acquisition device includes an assembly comprising a radiation emitter and detector rotatable about a patient for acquiring images of a portion of patient anatomy at different angles. The imaging controller initiates acquisition of data representing multiple images in the presence of a contrast agent of relatively long persistence by repetitively, initiating rotation of the assembly to an angle, acquiring an image at the angle in response to the trigger signal and incrementally increasing the angle.

Abstract: A method for reconstruction of an actual three-dimensional image dataset of an object during a monitoring process is proposed. Two-dimensional X-ray projection images which correspond to a recording geometry are continuously recorded from different projection angles. The three-dimensional image dataset are reconstructed from a first number of these projection images, especially by a back projection method. The proportion of the oldest projection image contained in the current three-dimensional image dataset is removed from the three-dimensional image dataset and the proportion of the actual projection image is inserted in the three-dimensional image dataset after each recording of the actual projection image.

Abstract: The invention relates to a method and a device for determining the position of a part of a medical instrument with an x-ray sensitive sensor in a plane of an x-ray image using an x-ray facility having an x-ray beam source and a device, which is assigned to the beam source and influences the x-ray radiation emitted by the x-ray beam source, wherein a spatial region, in which the medical instrument is located, is scanned with x-ray radiation and at the same time x-ray radiation is detected with the x-ray-sensitive sensor with the device for influencing the x-ray radiation rotating at constant speed, the rotation being synchronized to the receipt of signals based on x-ray radiation with the x-ray-sensitive sensor and with the position of the part of the medical instrument in the plane of an x-ray image being determined based on the x-ray radiation detected with the x-ray-sensitive sensor.

Abstract: A method for recording and reconstructing a three-dimensional image dataset is proposed. A plurality of projection images are acquired under different recording geometries in relation to an object to be recorded by an X-ray apparatus, in particular a C-arm X-ray apparatus. At least two projection images are recorded for at least one recording geometry, in particular for every recording geometry. The three-dimensional image dataset is reconstructed from the project images.

Abstract: A method and system for multi-part left atrium (LA) segmentation in a C-arm CT volume is disclosed. Multiple LA part models, including an LA chamber body mesh, an appendage mesh, a left inferior pulmonary vein (PV) mesh, a left superior PV mesh, a right inferior PV mesh, and a right superior PV mesh, are segmented in a 3D volume. A volume mask is generated from the LA chamber mesh, the appendage mesh, and the PV meshes. Erosion is performed in the LA chamber body and a plurality of ostia regions in the volume mask. The plurality of ostia regions in the volume mask are refined using region growing, and a smooth mesh is fit to each ostia region. A consolidated LA mesh is generated from the volume mask and the parts of the LA mesh are relabeled in the ostia region based on part boundaries detected using an optimization approach.

Abstract: A method for displaying a motion compensated overlay includes receiving a model of a structure of interest, capturing an image depicting a region of interest and an instrument, determining whether the structure of interest is visible in the image, registering the model of the structure of interest to the image upon determining that the structure of interest is visible, and combining the model of the structure of interest with the image according to a registration to determine an overlay image.

Abstract: Methods, systems, and apparatus for obtaining a sequence of x-ray images are disclosed. An object of interest in a first x-ray image is detected and an area of interest, based on a predicted motion of the object of interest, is determined. A second x-ray image of the area of interest is acquired using spatial x-ray modification to control an x-ray to pass through a portion of a patient corresponding to the area of interest.

Abstract: A method and system for multi-part left atrium (LA) segmentation in a C-arm CT volume is disclosed. Multiple LA part models, including an LA chamber body mesh, an appendage mesh, a left inferior pulmonary vein (PV) mesh, a left superior PV mesh, a right inferior PV mesh, and a right superior PV mesh, are segmented in a 3D volume. The LA chamber body mesh and the appendage mesh may be segmented as a combined object and the PV meshes may be segmented subject to a statistical shape constraint. A consolidated LA mesh is generated from the segmented LA part models.

Abstract: A method is provided for supplying a 3D X-ray image data record for a moving object. The said object contains highly X-ray radiation-absorbent material. A correction is made in respect of the highly absorbent material in 2D forward projections obtained from a 3D-X-ray image data record. The forward projections are calculated using 3D motion fields, which are derived from original 2D X-ray image data records.

Abstract: To visually support a catheter ablation in the heart, three-dimensional image data have been used prior to the intervention. During ablation, the position of the catheter is pinpointed by an orientation system. The orientation system acquires electroanatomical 3D mapping data. The two-dimensional image data is assigned to the 3D mapping data in the correct position and dimensions which is a time-consuming step. The invention makes provision for the orientation system being in a fixed location relative to the X-ray system so that a positionally and dimensionally correct alignment of the X-ray image data set with the 3D mapping data is no longer required. An image or surface based 3D-3D alignment of the three-dimensional data acquired prior to the intervention with the three-dimensional X-ray image data is considerably less time-consuming than alignment thereof with the 3D mapping data and is more reliable because more structures is recognized in the three-dimensional X-ray image data.

Abstract: A method for displaying a motion compensated overlay includes receiving a model of a structure of interest, capturing an image depicting a region of interest and an instrument, determining whether the structure of interest is visible in the image, registering the model of the structure of interest to the image upon determining that the structure of interest is visible, and combining the model of the structure of interest with the image according to a registration to determine an overlay image.

Abstract: A method for recording a projection dataset of a object to be recorded using a plurality of X-ray sources is provided, which X-ray sources are spaced apart from one another on average by an angle ? relative to an isocenter. A plurality of projection images from different recording directions are recorded in succession while activating the corresponding X-ray sources. Two X-ray sources are activated in succession having a spacing of at least 2 ? relative to the isocenter.

Abstract: A method and system for intraoperative guidance in an off-pump mitral valve repair procedure is disclosed. A plurality of patient-specific models of the mitral valve are generated, each from pre-operative image data obtained using a separate imaging modality. The pre-operative image data from the separate imaging modalities are fused into a common coordinate system by registering the plurality of patient-specific models. A model of the mitral valve is estimated in real-time in intraoperative image data using a fused physiological prior resulting from the registering of the plurality of patient-specific models.

Abstract: To make interventional instruments such as catheters more easily identifiable in X-ray images, the catheters are provided with marking elements which can be recognized in the X-ray image. Examples of marking elements are sphere-shaped and ring-shaped marking elements, the ring-shaped marking elements being able to identify the catheters in the manner of a barcode and so being able to make different catheters distinguishable from one another in the X-ray image.

Abstract: A method for guiding transcatheter aortic valve implantations includes receiving an interventional 3D image of an aortic root reconstructed from a sequence of 2D images acquired from a C-arm computed tomography (CT) system being rotated about a patient through a predetermined number of degrees, segmenting the aortic root and detecting aortic root landmarks in the 3D image, where the aortic root landmarks include three lowest points of aortic root cusps, two coronary artery ostia, and three commissures points where the cusps meet, cropping an area inside the segmented aortic root out of the 3D volume for volume rendering, centering the 3D image on an intersection of two orthogonal planes, each containing the two detected coronary ostia, that are orthogonal to a plane spanned by three lowest points of the aortic root cusps, and volume rendering the 3D cropped aortic root image together with the detected landmarks onto a 2D image.

Abstract: A system and method of determining hemodynamic parameters of a patient is described. A background image data set is obtained prior to the administration of a contrast agent. A series of image data sets is obtained during the first passage of the bolus through a parenchymal volume. The pre-contrast-agent image is subtracted from image data sets obtained during the first passage of the contrast agent bolus, so that the amount of contrast agent in the volume may be determined. The time series of the amount of contrast agent is computed to determine the arterial input function (AIF) which may be used to determine a tissue impulse response, and hemodynamic parameters such as cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT).

Abstract: In order to achieve improved image quality in X-ray photographs, a medical X-ray imaging system, comprising a flat, planar X-ray source having a surface with X-ray focal points arranged adjacent to one another and an X-ray detector with a sensor surface, is provided. The X-ray source has a plurality of field emission guns with at least one field emission cathode and the surface with focal points of the X-ray source is larger in size than the sensor surface of the X-ray detector.

Abstract: A method and system for model-based fusion of multi-modal volumetric images is disclosed. A first patient-specific model of an anchor anatomical structure is detected in a first medical image acquired using a first imaging modality, and a second patient-specific model of the anchor anatomical structure is detected in a second medical image acquired using a second imaging modality. A weighted mapping function is determined based on the first patient-specific model of the anchor anatomical structure and the second patient-specific model of the anchor anatomical structure using learned weights to minimize mapping error with respect to a target anatomical structure. The target anatomical structure from the first medical image to the second medical image using the weighted mapping function. In an application of this model-based fusion to transcatheter valve therapies, the trachea bifurcation is used as the anchor anatomical structure and the aortic valve is the target anatomical structure.

Abstract: A tomogram of a body is provided. Projection-image data obtained by a radiation-based projection method is used for providing the tomogram. Initial voxel data are first specified for a plurality of voxels of the body. Synthetic projection-image data are generated based upon a projection rule modeling a course of the projection method. Projection-error data is determined by comparing the synthetic projection-image data with the real projection-image data. The projection-error data are imaged on the basis of a back-projection rule dependent on the projection rule so that voxel-error data are produced. Correction data is generated from the voxel-error data by a gradient-based optimizing algorithm, wherein corrected voxel data are generated using the correction data.

Abstract: Automatic measurement of morphometric and motion parameters of a coronary target includes extracting reference frames from input data of a coronary target at different phases of a cardiac cycle, extracting a three-dimensional centerline model for each phase of the cardiac cycle based on the references frames and projection matrices of the coronary target, tracking a motion of the coronary target through the phases based on the three-dimensional centerline models, and determining a measurement of morphologic and motion parameters of the coronary target based on the motion.