Method for generating image data relating to a virtually prescribable X-ray tube voltage from first and second CT image data
    12.
    发明授权
    Method for generating image data relating to a virtually prescribable X-ray tube voltage from first and second CT image data 有权
    用于从第一和第二CT图像数据生成与虚拟规定的X射线管电压有关的图像数据的方法

    公开(公告)号:US07856134B2

    公开(公告)日:2010-12-21

    申请号:US12457973

    申请日:2009-06-26

    IPC分类号: G06K9/00

    摘要: A method for generating image data relating to a virtually prescribable X-ray tube voltage U3 from first and second dual energy CT image data is disclosed. In at least one embodiment, the method includes providing the first and second CT image data; prescribing the virtual X-ray tube voltage U3 with U3≠U1 and U3≠U2, on the basis of the first and second CT image data for two prescribable base materials A, B; determining in each case a spatial density distribution ρA(x), ρB(x), assigned to the base materials A, B, in the reconstructed object volume, ρ(x)=ρA(x)+ρB(x) holds true for a density ρ(x) of a voxel x in the reconstructed object volume; providing an effective mass attenuation coefficient U3 for the base material A, and an effective mass attenuation coefficient U3 for the base material B, the effective mass attenuation coefficients U3 and U3 respectively being valid for an X-ray spectrum S(E, U3) assigned to the virtual X-ray tube voltage U3; and determining the image data as a third distribution of linear attenuation coefficients μ3(x) in the reconstructed object volume on the basis of the following relationship: μ3(x)= U3·ρA(x)+ U3·ρB(x).

    摘要翻译: 公开了一种从第一和第二双能量CT图像数据生成与虚拟规定的X射线管电压U3有关的图像数据的方法。 在至少一个实施例中,该方法包括提供第一和第二CT图像数据; 以U3≠U1和U3≠U2的虚拟X射线管电压U3为基础,基于两个可处方的基材A,B的第一和第二CT图像数据; 在每种情况下确定分配给重建对象体积中的基础材料A,B的空间密度分布和(r)A(x),(r),(x),(x)=&rgr; A(x)+ &rgr; B(x)对于重建对象体积中的体素x的密度和(r)(x)是正确的; 为基材A提供有效的质量衰减系数<αA> U3,对于基材B有效的质量衰减系数<αB> U3,有效质量衰减系数αA> U3和<αB> U3分别对 分配给虚拟X射线管电压U3的X射线光谱S(E,U3) 基于以下关系,将图像数据确定为重建对象体积中的线性衰减系数μ3(x)的第三分布:μ3(x)= <αA> U3·&rgr; A(x)+ <αB> U3·&rgr; B(x)。

    Method for generating image data relating to a virtually prescribable x-ray tube voltage from first and second CT image data
    13.
    发明申请
    Method for generating image data relating to a virtually prescribable x-ray tube voltage from first and second CT image data 有权
    用于从第一和第二CT图像数据产生与虚拟规定的X射线管电压有关的图像数据的方法

    公开(公告)号:US20100014737A1

    公开(公告)日:2010-01-21

    申请号:US12457973

    申请日:2009-06-26

    IPC分类号: G06K9/00

    摘要: A method for generating image data relating to a virtually prescribable X-ray tube voltage U3 from first and second dual energy CT image data is disclosed. In at least one embodiment, the method includes providing the first and second CT image data; prescribing the virtual X-ray tube voltage U3 with U3≠U1 and U3≠U2, on the basis of the first and second CT image data for two prescribable base materials A, B; determining in each case a spatial density distribution ρA(x), ρB(x), assigned to the base materials A, B, in the reconstructed object volume, ρ(x)=ρA(x)+ρB(x) holds true for a density ρ(x) of a voxel x in the reconstructed object volume; providing an effective mass attenuation coefficient U3 for the base material A, and an effective mass attenuation coefficient U3 for the base material B, the effective mass attenuation coefficients U3 and U3 respectively being valid for an X-ray spectrum S(E, U3) assigned to the virtual X-ray tube voltage U3; and determining the image data as a third distribution of linear attenuation coefficients μ3(x) in the reconstructed object volume on the basis of the following relationship: μ3(x)= U3·ρA(x)+ U3·ρB(x).

    摘要翻译: 公开了一种从第一和第二双能量CT图像数据生成与虚拟规定的X射线管电压U3有关的图像数据的方法。 在至少一个实施例中,该方法包括提供第一和第二CT图像数据; 以U3U1和U3U2为基础的虚拟X射线管电压U3,根据两个可处方基材A,B的第一和第二CT图像数据; 在每种情况下确定分配给重建对象体积中的基材A,B的空间密度分布rhoA(x),rhoB(x),rho(x)= rhoA(x)+ rhoB(x)对于 重建对象体积中体素x的密度rho(x); 为基材A提供有效的质量衰减系数3和基材B的有效质量衰减系数3,有效质量衰减系数3和3分别对于分配的X射线光谱S(E,U3)有效 到虚拟X射线管电压U3; 并根据以下关系确定图像数据为重建对象体积中的线性衰减系数mu3(x)的第三分布:mu3(x)= 3.rhoA(x)+ 3.rhoB(x)。

    Method and tomography unit for the reconstruction of a tomographic display of an object
    14.
    发明授权
    Method and tomography unit for the reconstruction of a tomographic display of an object 失效
    用于重建物体的断层显像的方法和断层摄影单元

    公开(公告)号:US07447295B2

    公开(公告)日:2008-11-04

    申请号:US11584544

    申请日:2006-10-23

    IPC分类号: H05G1/60

    摘要: A method is disclosed for reconstructing a tomographic representation of an object from projection data off a moving radiation source through this object onto a detector, filtering and back projection of the projection data being executed in the reconstruction. In an embodiment of the method, by using at least one identical spatial arrangement of the radiation source, the detector and a test object instead of the object to be scanned, there is determined by test projections and an iterative reconstruction technique, a filter that in the given arrangement results in an optimum filtering and back projection of the projection data of the test object for the tomographic representation. Further, the object is scanned instead of the test object in the given arrangement and projection data are determined. Finally, the reconstruction of the tomographic representation is carried out using these projection data and the filter determined. Moreover, an embodiment of a tomography unit for carrying out this method is also disclosed.

    摘要翻译: 公开了一种用于将通过该物体的运动辐射源的投影数据从物体重建成检测器的方法,对重建中正在执行的投影数据进行滤波和反投影。 在该方法的一个实施例中,通过使用辐射源,检测器和测试对象的至少一个相同的空间排列而不是要扫描的对象,通过测试投影和迭代重建技术来确定滤波器, 给定的布置导致用于断层图像的测试对象的投影数据的最佳滤波和反投影。 此外,在给定的布置中扫描对象而不是测试对象,并且确定投影数据。 最后,使用这些投影数据并确定滤波器来进行断层图像的重建。 此外,还公开了用于执行该方法的断层摄影单元的实施例。

    Method for removing ring artifacts from tomograms produced with the aid of a computed tomography unit
    15.
    发明授权
    Method for removing ring artifacts from tomograms produced with the aid of a computed tomography unit 失效
    借助于计算机断层摄影单元产生的断层图像中的环形伪影的方法

    公开(公告)号:US07391927B2

    公开(公告)日:2008-06-24

    申请号:US11225035

    申请日:2005-09-14

    申请人: Karl Stierstorfer

    发明人: Karl Stierstorfer

    IPC分类号: G06K9/40

    CPC分类号: A61B6/032 G06T11/005

    摘要: A method and a computed tomography unit are disclosed, that render it possible in a simple way to remove ring artifacts from tomograms Ik, particularly in the case of a fast feed of the recording region per revolution of the recording system of the computed tomography unit by calculating a ring artifact image Ik for each tomogram Ik. In this procedure, temporary ring artifact images Rtk are firstly calculated for each tomogram Ik, and subsequently the final ring artifact image Rk is formed for the purpose of correcting the respective tomogram Ik by averaging over at least a portion Tsub of the temporary ring artifact images Rtk, the temporary ring artifact images Rtk being rotated before averaging in such a way that the ring artifacts present in the temporary artifact images Rtk substantially coincide and their position substantially corresponds to the ring artifacts present in the tomogram Ik.

    摘要翻译: 公开了一种方法和计算机断层摄影单元,其可以以简单的方式从断层图像中去除环形伪影,特别是在每一周的记录区域的快速馈送的情况下 通过针对每个断层图像I N k计算环形伪像图像I N k来计算断层摄影单元的记录系统。 在该过程中,首先针对每个断层图像I N k来计算临时环形伪影图像R SUB,并且随后最终的环形伪影图像R≠K 其目的是通过对临时环形伪影图像Rt SUB的至少一部分T N进行平均来校正相应的断层图像I&lt; k&gt; 临时环形伪影图像Rt N在平均之前旋转,使得存在于临时假象图像Rt1k中的环形伪像基本上重合,并且它们的位置基本上对应于 存在于断层图像I 中的环形伪像。

    Computed tomography unit having an aperture stop
    16.
    发明授权
    Computed tomography unit having an aperture stop 有权
    具有孔径光阑的计算机断层摄影单元

    公开(公告)号:US07313214B2

    公开(公告)日:2007-12-25

    申请号:US11100531

    申请日:2005-04-07

    IPC分类号: A61B6/03 G01N23/083

    摘要: A computed tomography unit includes at least one X-ray tube, that scans an object in a fashion rotating in a circle or spiral about a z-axis, in combination with an oppositely situated detector having a multiplicity of detector rows. Each detector row includes an aperture Δz in the z-direction, having a multiplicity of detector elements. Between the X-ray tube and detector, a detector diaphragm is arranged that reduces the aperture Δz of the detector rows in the z-direction. The X-ray tube includes a focus, of variable location relative to the X-ray tube and which alternatingly assumes during scanning at least two different positions that have different z-coordinates relative to the X-ray tube R.

    摘要翻译: 计算机断层摄影单元包括至少一个X射线管,其以相对位置的具有多个检测器行的检测器的组合,以围绕z轴旋转的方式扫描物体或旋转物体。 每个检测器行包括沿z方向的孔径Deltaz,具有多个检测器元件。 在X射线管和检测器之间,布置了检测器膜片,其减小了检测器行在z方向上的孔径Deltaz。 X射线管包括相对于X射线管可变位置的焦点,并且在扫描期间交替地假设相对于X射线管R具有不同z坐标的至少两个不同位置。

    Method for compiling computer tomographic representations using a CT system with at least two angularly offset ray sources
    18.
    发明申请
    Method for compiling computer tomographic representations using a CT system with at least two angularly offset ray sources 有权
    使用具有至少两个角偏移射线源的CT系统来编译计算机断层图像的方法

    公开(公告)号:US20070025499A1

    公开(公告)日:2007-02-01

    申请号:US11491959

    申请日:2006-07-25

    摘要: A method is disclosed for compiling computer tomographic representations using a CT system with at least two angularly offset ray sources. A first ray cone with a relatively larger fan angle and a second ray cone with a relatively smaller fan angle scan an object circularly or spirally. The first ray cone generates a first dataset A and the second ray cone generates a dataset B. The dataset B of the smaller ray cone is supplemented with other data at the edge to give an expanded dataset B+ for reconstruction of the CT representation. The expanded dataset B+ of the second, smaller ray cone and the dataset A of the first, larger ray cone is subjected to a convolution operation to give datasets B+′ and A′. Finally, a back projection to reconstruct sectional images or volume data is respectively carried out from the convoluted datasets B+′ and A′. The dataset B is supplemented with data of the dataset A and supplementary data are removed from the dataset B+′ after the convolution but before the back projection.

    摘要翻译: 公开了一种使用具有至少两个角偏移射线源的CT系统来编译计算机断层图像表示的方法。 具有相对较大扇角的第一射线锥体和具有较小扇形角度的第二射线锥体圆形地或螺旋地扫描物体。 第一射线锥产生第一数据集A,第二射线锥生成数据集B.较小射线锥的数据集B在边缘被补充其他数据,以给出用于重建CT表示的扩展数据集B +。 将第二较小的光线锥体的扩展数据集B +和第一个较大的光线锥体的数据集A进行卷积运算,以给出数据集B +'和A'。 最后,从卷积数据集B +'和A'分别进行重建截面图像或体积数据的背投影。 数据集B补充数据集A的数据,并且在卷积之后但在反投影之前从数据集B +'中删除补充数据。

    Voxel-driven spiral reconstruction for cone-beam computer tomography
    20.
    发明申请
    Voxel-driven spiral reconstruction for cone-beam computer tomography 失效
    用于锥束计算机断层扫描的体素驱动螺旋重建

    公开(公告)号:US20060140338A1

    公开(公告)日:2006-06-29

    申请号:US10544291

    申请日:2004-01-28

    CPC分类号: G06T11/006 A61B6/027

    摘要: A method is disclosed for generating computer tomography images using a 3D image reconstruction method. According to the method, to scan an object to be examined using a cone-shaped bundle of rays originating from a focal point and a planar, preferably multi-line detector for detecting the bundle of rays, the focal point is displaced along a spiral trajectory around the object to be examined. The detector delivers output data corresponding to the detected radiation and image voxels from the scanned examined object are reconstructed from the optionally pre-processed output data, the image voxels reflecting the attenuation coefficients of the respective voxel. Each image voxel is reconstructed separately from projection data, which covers a projection angular range of at least 108° and an approximate weighting is carried out for each voxel considered in order to standardise the projection data using the voxel.

    摘要翻译: 公开了一种使用3D图像重建方法生成计算机断层图像的方法。 根据该方法,为了使用来自焦点的锥形光束和用于检测光束的平面,优选多线检测器来扫描待检查的物体,焦点沿着螺旋轨迹移位 围绕要检查的对象。 检测器提供与检测到的辐射相对应的输出数据,并且从可选的预处理的输出数据重建来自扫描的被检查物体的图像体素,反映各个体素的衰减系数的图像体素。 每个图像体素与投影数据分开重建,投影数据覆盖至少108°的投影角度范围,并且为了使用体素标准化投影数据,为每个体素执行近似权重。