Abstract: A method for temporally filtering medical images during a fluoroscopy guided intervention procedure includes providing a mask image, a fluoroscopy intervention image acquired at a current time during a medical intervention procedure, forming a subtraction image by subtracting the mask image from the intervention image, calculating a motion image of a moving structure in the subtraction image, forming a residual image by subtracting the motion image from the subtraction image, temporally filtering the residual image with a filtered image from a previous time, and adding the motion image to the temporally filtered residual image.

Abstract: A method to optimally set a position of a form filter in an x-ray image recording apparatus is proposed. The x-ray image recording apparatus has an x-ray radiation source and an x-ray radiation detector. An x-ray image is firstly recorded in a first position of the form filter. A new position of the filter is then calculated and automatically set with the aid of the x-ray image. A new x-ray image is then recorded. With a minimal dose of a patient, the method enables low contrast images to be recorded for a minimal main dose of the patient, in particular in a sequence.

Abstract: The invention relates to a method for noise suppression in medical images comprising steps of measuring the gradient field strength of an image pixel and selecting a suitable filter mask for noise suppression as a function of the gradient field strength, with the value of the gradient field strength being compared with a predetermined threshold value. The method is repeated when an additional image pixel is selected. A decision is made per read-in image pixel as to which type of filter mask is used for filtering. A selection can be made between filter masks of different sizes or isotropic or anisotropic or directional filter masks. The decision is based on the measured gradient field strength of the respective pixel. The use of different filter masks allows the signal-to-noise ratio to be improved, without distorting structures like edges for instance and without generating artificial structures in homogenous noise regions.

Abstract: Modern image processing systems for the postprocessing of X-ray images require a large number of input parameters and take a great deal of time. So that calculations do not need to be made sequentially for different sets of input parameters, parallel processors are used, in which the same image processing program is executed in each case, but with different input parameters in each case. A large number of processed X-ray images is thus obtained, which in particular can also be displayed simultaneously. From the multiple processed x-ray images, a repeated postprocessing of a processed x-ray image can take place by mixing.

Abstract: The invention relates to a method for presentation of medical images by a reproduction facility of a diagnostic device with suppression of the noise with the following steps: one-off calibration of the signal-dependent noise; separation of the signal and noise components in the image; adaptation of the two components according to set parameters; and composition of the signals.

Abstract: A method for setting a control variable of a filter for noise reduction in medical images is provided. Image data of the medical images is classified into at least one noise region and at least one structure region. A variance measurement is performed either for all the image pixels or a subset of them to determine the edge thicknesses. A histogram is generated from the edge thicknesses. The maximum of the histogram is determined and a Gaussian curve is fitted to the histogram. A threshold value for noise and structure is determined as a function of the standard deviation of the Gaussian curve. The noise and structure are measured in the regions. The standard noise and structure deviations are determined and compared. The control variable is setup as a function of the comparison of noise and structure. The invention can be used for reduction of temporal noise in bandpass images.

Abstract: A method and system for vessel segmentation in fluoroscopic images is disclosed. Hierarchical learning-based detection is used to perform the vessel segmentation. A boundary classifier is trained and used to detect boundary pixels of a vessel in a fluoroscopic image. A cross-segment classifier is trained and used to detect cross-segments connecting the boundary pixels. A quadrilateral classifier is trained and used to detect quadrilaterals connecting the cross segments. Dynamic programming is then used to combine the quadrilaterals to generate a tubular structure representing the vessel.

Abstract: The present invention relates to a method, which assists a doctor for instance in orientation in 2D fluoroscopy images. The present invention relates here to a method for displaying co-registered 2D-3D images in medical imaging, comprising the following steps: determine a 3D or 2D projection which is congruent with a 2D image from a 3D image data set, and overlaid display of the 2D image with the 3D or 2D projection on a monitor, characterized in that the two image parts of the two overlaid images can be adjusted and a shift in the two overlaid images which can be adjusted in at least one direction is enabled.

Abstract: A method and system for correcting butting artifacts in x-ray images is disclosed. In order to correct a butting artifact in an x-ray image, a butting artifact region in the x-ray image is normalized. Multiple intensity shift estimators are calculated for each pixel of each line of the butting artifact. Confidence intervals are calculated for each intensity shift estimator. A multiple hypothesis hidden Markov model (MH-HMM) is formulated based on the intensity shift operators and confidence measures subject to a smoothness constraint, and the MH-HMM is solved to determine intensity shift values for each pixel. A corrected image is generated by adjusting the intensity of each pixel of the butting artifact based on the intensity shift value for that pixel.

Abstract: The present invention relates to a method for image reproduction, in particular for single or serial medical exposures, whereby one or more main images are reproduced on a display device. The method is characterized in that additional or interim images are generated using image interpolation prior to image reproduction from the one or more main images and in that additional image noise which varies from image to image is applied to the one or more main images and the additional or interim images, said image noise being generated by a noise generator, and image reproduction taking place by displaying in chronological order the one or more main images and additional or interim images to which the additional image noise has been applied. The method in particular improves the visual image impression in the case of fluoroscopic X-ray image exposures, without having to increase the applied X-ray dose.

Abstract: A method for enhancing stent visibility in digital medical images includes providing a time series of 2-dimensional (2D) images of a stent in a vessel, estimating motion of the stent in a subset of images of the time series of images, estimating motion of clutter in the subset of images, where clutter comprises anatomical structures other than the stent, estimating a clutter layer in the subset of images from the estimated clutter motion, estimating a stent layer in the subset of images from the clutter layer and the estimated clutter motion, and minimizing a functional of the estimated stent motion, the estimated stent layer, the estimated clutter motion, and the estimated clutter layer to in calculate a refined stent layer image, where the refined stent layer image has enhanced visibility of the stent.

Abstract: A method for checking an x-ray diagnostic apparatus is provided. Fluoroscopic series of x-ray images of a technical phantom are digitally acquired and stored. Difference between a dynamic image and a background image is calculated. A measuring field is predicted. Priori information about the shape of a clinically relevant object is determined. Hough transformation on a gray value image corresponding to the difference is applied. Contrast of the object from the Hough-transformed gray value image is determined. A square of the determined contrast is calculated. A noise variance is calculated by determining a sum of a noise variance of a homogenous image region and a variance of the background image. A contrast-to-noise ratio of the determined contrast and the calculated noise variance is determined. A square of the contrast-to-noise ratio is dynamically averaged. A Clinical Relevant Fluoroscopy Performance index for the x-ray diagnostic apparatus is determined.

Abstract: The invention relates to a new, advantageous method for the preparation of dialkyl ?-fluoromalonates.

Abstract: A method for temporally filtering medical images during a fluoroscopy guided intervention procedure includes providing a mask image, a fluoroscopy intervention image acquired at a current time during a medical intervention procedure, forming a subtraction image by subtracting the mask image from the intervention image, calculating a motion image of a moving structure in the subtraction image, forming a residual image by subtracting the motion image from the subtraction image, temporally filtering the residual image with a filtered image from a previous time, and adding the motion image to the temporally filtered residual image.

Abstract: A method for setting a control variable of a filter for noise reduction in medical images is provided. Image data of the medical images is classified into at least one noise region and at least one structure region. A variance measurement is performed either for all the image pixels or a subset of them to determine the edge thicknesses. A histogram is generated from the edge thicknesses. The maximum of the histogram is determined and a Gaussian curve is fitted to the histogram. A threshold value for noise and structure is determined as a function of the standard deviation of the Gaussian curve. The noise and structure are measured in the regions. The standard noise and structure deviations are determined and compared. The control variable is setup as a function of the comparison of noise and structure. The invention can be used for reduction of temporal noise in bandpass images.

Abstract: Modern image processing systems for the postprocessing of X-ray images require a large number of input parameters and take a great deal of time. So that calculations do not need to be made sequentially for different sets of input parameters, parallel processors are used, in which the same image processing program is executed in each case, but with different input parameters in each case. A large number of processed X-ray images is thus obtained, which in particular can also be displayed simultaneously. From the multiple processed x-ray images, a repeated postprocessing of a processed x-ray image can take place by mixing.

Abstract: The invention provides the use of mixtures based on aqueous dispersions of polychloroprene to produce fiber products finished therewith, a process for the production thereof and the use of these finished fiber products to produce textile-reinforced and fiber-reinforced concrete and other products based on cement.

Abstract: A method for checking an x-ray diagnostic apparatus is provided. Fluoroscopic series of x-ray images of a technical phantom are digitally acquired and stored. Difference between a dynamic image and a background image is calculated. A measuring field is predicted. Priori information about the shape of a clinically relevant object is determined. Hough transformation on a gray value image corresponding to the difference is applied. Contrast of the object from the Hough-transformed gray value image is determined. A square of the determined contrast is calculated. A noise variance is calculated by determining a sum of a noise variance of a homogenous image region and a variance of the background image. A contrast-to-noise ratio of the determined contrast and the calculated noise variance is determined. A square of the contrast-to-noise ratio is dynamically averaged. A Clinical Relevant Fluoroscopy Performance index for the x-ray diagnostic apparatus is determined.

Abstract: The invention relates to a method for noise suppression in medical images comprising steps of measuring the gradient field strength of an image pixel and selecting a suitable filter mask for noise suppression as a function of the gradient field strength, with the value of the gradient field strength being compared with a predetermined threshold value. The method is repeated when an additional image pixel is selected. A decision is made per read-in image pixel as to which type of filter mask is used for filtering. A selection can be made between filter masks of different sizes or isotropic or anisotropic or directional filter masks. The decision is based on the measured gradient field strength of the respective pixel. The use of different filter masks allows the signal-to-noise ratio to be improved, without distorting structures like edges for instance and without generating artificial structures in homogenous noise regions.

Abstract: The invention relates to an angiographic x-ray diagnostic apparatus with an x-ray radiator having an x-ray tube, with a patient positioning table having a radiation-transparent positioning plate and mattress, with an x-ray detector, with an imaging system, an image processing unit and a measuring device to which the output signals of the x-ray detector are fed and which has a first device for determining a value determining the reproduction quality of clinically relevant objects, a second device for determining local variances of the noise in a homogenous image region of different x-ray images and a device for taking the ratio of the output values of the two devices.