Patent application number | Description | Published |
20080275335 | Methods and apparatus for virtual coronary mapping - A virtual map of vessels of interest in medical procedures, such as coronary angioplasty is created so that doses of contrasting agent given to a patient may be reduced. A position of a coronary guidewire is determined and locations of vessel boundaries are found. When the contrast agent has dissipated, virtual maps of the vessels are created as new images. The locations of the determined vessel boundaries are imported to a mapping system and an image obtained without using a contrast agent is modified based on the imported locations of vessel boundaries. This creates a virtual map of the vessels. | 11-06-2008 |
20090080728 | Method and system for vessel segmentation in fluoroscopic images - 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. | 03-26-2009 |
20090080756 | Method and system for correcting butting artifacts in X-ray images - 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. | 03-26-2009 |
20090097732 | Procedures for the presentation of medical images - 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. | 04-16-2009 |
20090148015 | Method and device for noise suppression in medical images - 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. | 06-11-2009 |
20090169088 | METHOD FOR OPERATING AN X-RAY DIAGNOSTIC APPARATUS FOR DETERMINING QUALITY VALUES - 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. | 07-02-2009 |
20090257637 | Method for providing variously processed image data and x-ray image system - 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. | 10-15-2009 |
20090285461 | METHOD FOR SETTING AT LEAST ONE CONTROL VARIABLE OF A FILTER FOR NOISE REDUCTION IN MEDICAL IMAGES - 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. | 11-19-2009 |
20100092061 | SYSTEM AND METHOD FOR DECOMPOSED TEMPORAL FILTERING FOR X-RAY GUIDED INTERVENTION APPLICATION - 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. | 04-15-2010 |
20110064285 | SYSTEM AND METHOD FOR MULTI-IMAGE BASED STENT VISIBILITY ENHANCEMENT - 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. | 03-17-2011 |
20120300905 | Method for obtaining image data with the aid of an x-ray image recording apparatus having a filter and an x-ray image recording apparatus - 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. | 11-29-2012 |