摘要:
The invention relates to an X-ray detector (1) with an array (2) of sensor elements (21), wherein each row (i) of sensor elements is connected via an addressing line to an addressing unit (5), and wherein each column j) of sensor elements is connected via a read-out line to a read-out unit (3). In the read-out unit (3), sensor signals are preprocessed, for example amplified by amplifiers (31). The detector further comprises a control unit (6) which is adapted to set the gains of said amplifiers (31) for each column (j) and each row (i) individually. The values of the gains may particularly be derived from a priori knowledge, from previous images of the object, or from the image signals of rows that have already been read out.
摘要:
The invention relates to an X-ray detector (1) with an array (2) of sensor elements (21), wherein each row (i) of sensor elements is connected via an addressing line to an addressing unit (5), and wherein each column j) of sensor elements is connected via a read-out line to a read-out unit (3). In the read-out unit (3), sensor signals are preprocessed, for example amplified by amplifiers (31). The detector further comprises a control unit (6) which is adapted to set the gains of said amplifiers (31) for each column (j) and each row (i) individually. The values of the gains may particularly be derived from a priori knowledge, from previous images of the object, or from the image signals of rows that have already been read out.
摘要:
Adaptively controlling an imaging system (200, 205) includes constructing model feature characteristics (105) of a process over time, determining parameters and commands (110) for controlling the imaging system for each state of the process, performing data acquisition (120) for the process, extracting current features (130) of the process from the acquired data, matching (135) the current features (130) with the model feature characteristics (105) to determine a state of the process (140), and controlling the data acquisition based on the state of the process to produce optimized data.
摘要:
The invention relates to an apparatus and a method for the processing of reconstructed 3D images (I) in C-arm based volume imaging which often exhibit spatially slowly varying inhomogeneities caused by inconsistent projection data. To correct the images (I), a retrospective homogenization procedure is proposed. The image (I) is segmented (11, 12) into principal classes like bone, tissue and air based on their gray values. Only the tissue-regions (M) are then used as support in order to fit (14) a spatially slowly varying 2D baseline (B) representing the smooth shape of cupping or other inhomogeneities. Finally the inverse of the estimated 2D baseline is subtracted from the original slice (I) to correct for the inhomogeneities.
摘要:
Adaptively controlling an imaging system (200, 205) includes constructing model feature characteristics (105) of a process over time, determining parameters and commands (110) for controlling the imaging system for each state of the process, performing data acquisition (120) for the process, extracting current features (130) of the process from the acquired data, matching (135) the current features (130) with the model feature characteristics (105) to determine a state of the process (140), and controlling the data acquisition based on the state of the process to produce optimized data.
摘要:
A method includes generating enhanced image data based on lower dose image data and a predetermined image quality threshold, wherein an image quality of the enhanced image data is substantially similar to an image quality of higher dose image data, and a system includes an image quality enhancer (128) that generates enhanced image data based on lower dose image data and a predetermined image quality threshold, wherein an image quality of the enhanced image data is substantially similar to an image quality of higher dose image data.
摘要:
A method includes generating a plurality of scatter distributions based on geometric models having different object to detector distances, determining an imaged object to detector distance, and identifying a scatter distribution of the plurality of scatter distributions having a object to detector distance that corresponds to the imaged object to detector distance. The method also includes employing the identified scatter distribution to scatter correct projection data corresponding to the imaged object. Another method includes generating an estimate of wedge scatter by propagating a predetermined wedge scatter profile through an intermediate reconstruction of an object; and employing the estimate to wedge scatter correct the projection data.
摘要:
Method of generating an image of an object by means of an imaging system which has a radiation source that rotates relative to the object about an axis of rotation within a defined rotation angle range, said radiation source projecting radiation onto a radiation detector in order to record projection data, wherein at predefinable relative rotation angle positions of the radiation source a signal which is used to trigger recording of the projection data is generated, and also apparatus for carrying out this method.
摘要:
When generating a 3D image of a subject or patient, a cone beam X-ray source (20a, 20b) is mounted to a rotatable gantry (14) opposite an offset flat panel X-ray detector (22a, 22b). A wedge-shaped attenuation filter (24a, 24b) of suitable material (e.g., aluminum or the like) is adjustably positioned in the cone beam to selectively attenuate the beam as a function of the shape, size, and density of a volume of interest (18) through which X-rays pass in order to maintain X-ray intensity or gain at a relatively constant level within a range of acceptable levels.
摘要:
When generating a 3D image of a subject or patient, a cone beam X-ray source (20a, 20b) is mounted to a rotatable gantry (14) opposite an offset flat panel X-ray detector (22a, 22b). A wedge-shaped attenuation filter (24a, 24b) of suitable material (e.g., aluminum or the like) is adjustably positioned in the cone beam to selectively attenuate the beam as a function of the shape, size, and density of a volume of interest (18) through which X-rays pass in order to maintain X-ray intensity or gain at a relatively constant level within a range of acceptable levels.