摘要:
The invention relates to an image processing method for improving the signal-to-noise ratio for a series of MR images or CT images which are based on the projection-reconstruction method. First the pixels which reproduce the same sub-structure in the projection images are determined in the one-dimensional projection images constituting the two-dimensional MR or CT images. The image values of these pixels are subjected to noise filtering. Two-dimensional MR images or CT images are reconstructed from the noise filtered one-dimensional projection images.
摘要:
A MR method determines nuclear magnetic resonance distribution in an examination area and the position of at least one microcoil which is located in the examination area in or on an examination object. In the presence of a homogeneous stationary magnetic field acting on the examination area, sequences are carried out in which at least one high-frequency pulse acting on the examination area is generated, and after the high-frequency pulse an MR signal induced in the microcoil is detected under the influence of a gradient magnetic field that acts on the examination area. Then the position of the microcoil in the gradient direction defined by the gradient field is derived from the detected MR signal. The aforementioned sequences are repeated for another gradient direction, and MR signals are detected by a further receiving coil arrangement to determine the nuclear distribution. Without additional measuring sequences, a position is detected in a manner that the sequences are continuously repeated while the gradient direction is varied, and that the position of the microcoil and the nuclear magnetic distribution are derived from MR signals detected simultaneously by the microcoil and the receiving coil arrangement.
摘要:
The invention relates to a method of forming a series of MR images in which, in the presence of a steady magnetic field, sequences comprising at least an RF pulse and a magnetic gradient field which is varied from one sequence to another are continuously applied to the examination zone, from the image signals thus generated there being reconstructed MR images, the oldest MR signals used for the reconstruction of an MR image being replaced upon reconstruction of the next MR image by the respective newly generated MR signals. Low-artefact reproduction of dynamic processes in the examination zone can be achieved by varying the direction of the magnetic gradient field active during the generation of an MR signal from one sequence to another so that the range of the magnetic gradient field directions required for the reconstruction is distributed between the respective newly generated MR signals. The invention also relates to a device for carrying out this method.
摘要:
The present invention relates to visualizing information of an object. In order to provide spatial information and in addition situation specific data to the user while ensuring an effective perceptibility, a method (110) is provided comprising the steps of: a) providing (112) pre-navigation data (114) of a region of interest of an object (22); wherein the pre-navigation data comprises spatial geometrical data (116) and a functional parameter surface (118) in correspondence to the spatial geometrical data; b) acquiring (120) live image data (122) of the region of interest; c) detecting (124) an element (126) in the live image data; d) determining (128) spatial relation (130) of the pre-navigation data and the live image data; e) determining (132)the position (134) of the detected element in the spatial geometrical data, which determining is based on the spatial relation, and computing (136) a predetermined related point of location (138) on the functional parameter surface; f) generating (140) a combination (142) of a simplified surface representation (144) of the region of interest, which simplified surface representation is based on a visualization of the functional parameter surface, and a marker (146) indicating the computed predetermined related point of location; and g) displaying (148) the combination as navigation guidance (150).
摘要:
A magnetic field unit of an MRT system for image capturing a head region as the region to be recorded, comprising at least one permanent magnet for generating a main magnetic field, a device for generating a gradient field, and at least one coil for generating and receiving radio frequencies. The magnetic field unit is fastened to a mounting such that a longitudinal axis of the magnetic field unit, together with a vertically extending axis, forms an angle of no more than +45 degrees, and the magnetic field unit and the patient can be adjusted relative to each other such that the magnetic field unit can be moved to a position surrounding the head of the patient.
摘要:
The present invention relates to visualizing information of an object. In order to provide spatial information and in addition situation specific data to the user while ensuring an effective perceptibility, a method (110) is provided comprising the steps of: a) providing (112) pre-navigation data (114) spatial geometrical data (116) and a functional parameter surface (118) of a region of interest of an object (22); wherein the pre-navigation data comprises in correspondence to the spatial geometrical data; b) acquiring (120) live image data (122) of the region of interest; c) detecting (124) an element (126) in the live image data; d) determining (128) spatial relation (130) of the pre-navigation data and the live image data; e) determining (132)the position (134) of the detected element in the spatial geometrical data, which determining is based on the spatial relation, and computing (136) a predetermined related point of location (138) on the functional parameter surface; f) generating (140) a combination (142) of a simplified surface representation (144) of the region of interest, which simplified surface representation is based on a visualization of the functional parameter surface, and a marker (146) indicating the computed predetermined related point of location; and g) displaying (148) the combination as navigation guidance (150).
摘要:
A method for operating an imaging system, and a system, apparatus, and computer-readable medium, that operate in accordance with the method. The method includes providing field-of-view (FoV) information, and automatically selecting at least one recording sequence based on at least one of a particular diagnostic application of interest and the FoV information.
摘要:
The invention relates to an imaging system and a method for generating high-quality X-ray projections (24) of a patient (1). The system comprises a rotational X-ray device (10), for example a cone-beam CT-gantry (12), and an associated data processing unit (20). During a medical intervention, low-dose raw projections (22) of the patient (1) are continuously generated from different directions. A volume of interest (23) is then reconstructed from said projections (22), from which high-quality virtual projections (24) can be calculated for a display on a monitor (25). The number and direction of said virtual projections (24) can be arbitrarily chosen by the user.
摘要:
A method for the three-dimensional reconstruction of an object, or its surroundings, in a moving body volume of a patient includes obtaining a series of X-ray projection photographs produced from different directions, with a relevant ECG phase or respiration being recorded simultaneously. Projection photographs of the moving body volume are transformed such that the images of feature points that are located on the projection photographs respectively come to rest at a place on which randomly set spatial reference positions for the feature points are projected. With the projection photographs aligned onto the reference positions, three-dimensional reconstruction of the object can subsequently take place.
摘要:
In three-dimensional rotational x-ray coronary imaging problems may arise when estimating the motion of small vessels. According to an exemplary embodiment of the present invention, an examination apparatus is provided which is adapted for performing a hierarchical motion estimation by global affine transformation for every heart phase, followed by vessel branch selective affine and non-affine transformations. This may provide for an improved image quality.