Patent application number | Description | Published |
20080247624 | Method for determining a three-dimensional reconstruction of an examination object - A provisional three-dimensional reconstruction of an examination object is determined based on two-dimensional original projection images. Provisional metal volumes are determined on the reconstruction by segmentation and mapped into the original projection images to define provisional metal areas. Edge points on edge zones of the provisional metal areas are selected. Data values of the original projection images within the provisional metal areas are modified as a function of data values of the selected edge points to determine modified projection images. Differential images are determined based on the original projection images and the corresponding modified projection images. Definitive metal areas are determined in the differential images by segmentation. The differential images are added to the modified projection images with the definitive metal areas deducted. A definitive three-dimensional reconstruction of the examination object is determined based on the modified projection images including the added differential images. | 10-09-2008 |
20090086883 | Method for creating material-selective volume images - A method for creating material-selective volume images of various material components of an object to be examined is proposed. The method is based on multi-spectral projected images captured from various directions of projection, the images being captured using an X-ray machine, and makes it possible to quantitively exactly determine the material-selective volume images by way of iteration. | 04-02-2009 |
20090175407 | Computer tomography method for determining an object region - In a computer tomography method an object region of the object being examined is determined in that projection beams that are linked with maximum attenuation are sought in cropped projection images. A central point of the object region is then determined and the object sections associated with the projection beams plotted on the central point. The object region can be at least approximately determined using the end points of the object sections. | 07-09-2009 |
20100053203 | Contrast Increase in X-Ray Projection Images and/or in Tomographically Reconstructed Volumes by Deconvolution of the Projection Images - The invention relates to a method and a device for increasing contrast in medical images generated by an imaging system featuring an x-ray source and a detector. The detector detects x-rays of the x-ray source and converts image signals from the x-rays. The image signals are transferred to a control and processing unit for processing. Deconvolution of the image signals is carried out by application of an inverse modulation transfer function modified by a regularization. At least a volume image can be reconstructed from the deconvolved image signals. | 03-04-2010 |
20100246918 | ITERATIVE EXTRA-FOCAL RADIATION CORRECTION IN THE RECONSTRUCTION OF CT IMAGES - A method is disclosed for reconstruction of image data of an object under examination from measurement data, with the measurement data having been recorded during a rotating movement of a radiation source of a computed tomography system around the object under examination. The radiation source emits focal and extra-focal radiation. In at least one embodiment of the method, the image data is determined from the measurement data by use of an iterative algorithm. A variable is used in the iterative algorithm which contains a distribution of the extra-focal radiation. | 09-30-2010 |
20120008740 | METHOD FOR RECONSTRUCTION OF A THREE-DIMENSIONAL IMAGE DATA SET AND X-RAY DEVICE - A method for reconstruction of a three-dimensional image data set from projection images of an object captured with an X-ray device from different projection angles is proposed. At least one sub-area of the object is outside the coverage of the X-ray device, or as a result of strong attenuation by a metal so that no projection data is present in the sub-area. Filter lines are determined n the projection images. A first local transformation is performed along the filter lines on the projection images. The missing projection data on the transformed projection data is augmented. A non-local transformation is performed on the transformed projection data for determining of filtered, augmented projection data. The non-local transformation is different from a ramp filter which is created by the first local transformation and the non-local transformation. The three-dimensional image data set is determined by back-projection of the filtered, augmented projection data. | 01-12-2012 |
20120237115 | Method for acquiring a 3D image dataset freed of traces of a metal object - An interpolation of data values is performed during the acquisition of a 3D image dataset which is free of traces of a metal object imaged in the underlying 2D image datasets. A target function is defined into which data values of the 3D image dataset that are dependent on said substitute data values are incorporated following preprocessing. The substitute data values are then varied iteratively until the value of the target function satisfies a predetermined criterion. Residual artifacts that still persist following the interpolation can thus be effectively reduced. | 09-20-2012 |
20120275656 | METHOD FOR SUPPLYING A 3D X-RAY IMAGE DATA RECORD FOR A MOVING OBJECT WITH HIGHLY ABSORBENT MATERIAL - 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. | 11-01-2012 |
20130004051 | METHOD FOR ACQUIRING A 3D IMAGE DATASET FOR AN IMAGE OBJECT - A method for acquiring a 3D image dataset for an image object based on a plurality of 2D image datasets relating to the image object is proposed. A scattered radiation is taken into account in an acquisition operator used in the method for the optimum reconstruction of the 3D image dataset. The acquisition operator should be as close as possible to the real mapping operator. | 01-03-2013 |