公开(公告)号：US5987091A

公开(公告)日：1999-11-16

申请号：US897530

申请日：1997-07-21

申请人： Osamu Miyazaki ,  Shinichi Migita ,  Tetsuo Nakazawa

发明人： Osamu Miyazaki ,  Shinichi Migita ,  Tetsuo Nakazawa

IPC分类号： A61B6/03 ,  G06T11/00

CPC分类号： G06T11/005 ,  Y10S378/901

摘要： Projection data having a phase difference of 180.degree. from each other, which are obtained through a 1/4 offset detector, are arranged alternately to obtain projection data of the high resolution, and a CT image is reconstructed on the basis of the projection data of the high resolution. Opposition difference data showing the difference between the projection data having the phase difference of 180.degree. from each other and having a phase difference of 180.degree. from each other are alternately arranged to obtain the opposition difference data of the high resolution, and an opposition difference image is reconstructed on the basis of the opposition difference data of the high resolution. Then, distortion components showing the high-frequency component are extracted from the aforesaid opposition difference image, and the aforesaid reconstructed CT image is corrected by the thus extracted distortion components, so that motion artifacts contained in the original CT image can be reduced.

摘要翻译： 通过+ E，fra 1/4 + EE偏移检测器获得的相位差为180度的投影数据交替排列以获得高分辨率的投影数据，并且在 高分辨率投影数据的基础。 交替地布置表示彼此具有180度的相位差并具有180度的相位差的投影数据之间的差异的反差差数据，以获得高分辨率的对数差分数据和对置差分图像 基于高分辨率的对数差分数据重建。 然后，从上述对立差分图像中提取示出高频分量的失真分量，并且通过这样提取的失真分量校正上述重建的CT图像，从而可以减少包含在原始CT图像中的运动伪影。

公开(公告)号：US5615279A

公开(公告)日：1997-03-25

申请号：US332090

申请日：1994-11-01

申请人： Tomonori Yoshioka ,  Shinichi Migita ,  Tetsuo Nakazawa

发明人： Tomonori Yoshioka ,  Shinichi Migita ,  Tetsuo Nakazawa

IPC分类号： G01N23/04 ,  A61B6/03 ,  G06T11/00 ,  G06K9/36

CPC分类号： H01J35/14 ,  A61B6/583 ,  G06T11/005 ,  H01J2235/086

摘要： In a scattered X-ray correction method for an X-ray computerized tomograph, the quantity of X-rays passed through a phantom is measured to be converted into logarithms. Obtained from the logarithmic data is a scattered X-ray correction curve representing a relationship between the measured data in the logarithmic expression and an amount of scattered X-ray correction. For a subject, the quantity of X-rays penetrated therethrough is measured to be transformed into logarithms. From the measured data undergone the logarithmic conversion and the scattered X-ray correction curve, there is attained a scattered X-ray correction amount in a linear region which is the state before the logarithmic conversion. The measured data of the subject in the logarithmic expression is subjected to an inverse logarithmic conversion. From the obtained values, the scattered X-ray correction amount is subtracted such that the resultant values are again converted into logarithms, thereby producing a computerized tomogram from the logarithmic values.

摘要翻译： 在X射线计算机断层摄影机的散射X射线校正方法中，测量通过体模X射线的量被转换成对数。 从对数数据获得的散射X射线校正曲线表示对数表达式中的测量数据与散射X射线校正量之间的关系。 对于受试者，穿过其中的X射线的量被测量以被转换成对数。 从经过对数转换和散射X射线校正曲线的测量数据，在对数转换之前的状态的线性区域中获得散射X射线校正量。 以对数表达式对象的测量数据进行逆对数转换。 从获得的值中减去散射X射线校正量，使得所得到的值再次转换成对数，从而从对数值产生计算机断层图像。

公开(公告)号：US5454019A

公开(公告)日：1995-09-26

申请号：US851930

申请日：1992-03-16

申请人： Shinichi Migita ,  Osamu Miyazaki ,  Testuo Nakazawa

发明人： Shinichi Migita ,  Osamu Miyazaki ,  Testuo Nakazawa

IPC分类号： A61B6/03 ,  G01N23/04 ,  G06T11/00 ,  G01N23/083

CPC分类号： A61B6/032 ,  G01N23/046 ,  G06T11/005 ,  G01N2223/419 ,  G01N2223/612 ,  Y10S378/901

摘要： A computed tomography system includes an image reconstruction data generator for generating image reconstruction data for a desired slice plane of an object in accordance with measuring projection data, the image reconstruction data being obtained from measuring projection data obtained at each of a plurality of rotation positions of a radiation source, and an image reconstructor for obtaining tomographic image data of the object for the desired slice plane in accordance with the image reconstruction data. The image reconstruction data generator has the capability of grouping the measuring projection data into a plurality of groups respectively corresponding to a plurality of desired slice planes of the object, the desired slice planes being spaced apart from each other by a distance corresponding to one rotation position of the radiation source, with each of the groups corresponding to a continuous rotation range of 360.degree. of the radiation source, and successively using the measuring projection data of each group for the image reconstruction data.

摘要翻译： 计算机断层摄影系统包括图像重建数据发生器，用于根据测量投影数据产生对象的期望切片平面的图像重建数据，所述图像重建数据是从测量在多个旋转位置 辐射源，以及图像重建器，用于根据图像重建数据获得用于期望切片平面的物体的断层图像数据。 图像重建数据生成器具有将测量投影数据分组成分别对应于对象的多个期望切片平面的多个组的能力，期望的切片平面彼此间隔一个相当于一个旋转位置的距离 的辐射源，其中每个组对应于辐射源的360°的连续旋转范围，并且连续地使用每组的测量投影数据作为图像重建数据。

公开(公告)号：US5590164A

公开(公告)日：1996-12-31

申请号：US456382

申请日：1995-06-01

申请人： Hiroyuki Kawai ,  Kensuke Sekihara ,  Shinichi Migita

发明人： Hiroyuki Kawai ,  Kensuke Sekihara ,  Shinichi Migita

IPC分类号： A61B6/03 ,  G06T11/00 ,  A61B6/00

CPC分类号： A61B6/032 ,  A61B6/4021 ,  A61B6/4078 ,  G06T11/005

摘要： An X-ray computed tomography apparatus includes a controller for shifting an X-ray focal spot position of an X-ray source, a plurality of first temporary holding devices respectively connected to X-ray detector elements to temporarily hold measured values of X-ray intensity transmitted through an object to be incident on the X-ray detector elements, a switch device for switching over connection between the X-ray detector elements and the first temporary holding devices, a controller for controlling switchover of the switch device, a transfer device for transferring the measured values from the first temporary holding devices to an interpolation calculating device, an interpolation calculating device for performing interpolation calculations on the projection data to generate projection data equivalent to projection data measured by using a measuring system virtually having twice as many X-ray detector elements as the arranged X-ray detector elements, a memory for holding parameters used for calculations in the interpolation calculating device, and an image reconstructor for reconstructing a tomographic image on the basis of the projection data generated by interpolation calculating device.

摘要翻译： X射线计算机断层摄影装置包括用于移动X射线源的X射线焦斑位置的控制器，分别连接到X射线检测器元件的多个第一临时保持装置，以暂时保持X射线的测量值 透过要入射到X射线检测器元件上的物体的强度，用于切换X射线检测器元件和第一临时保持装置之间的连接的开关装置，用于控制开关装置的切换的控制器， 用于将测量值从第一临时保持装置传送到插值计算装置;插值计算装置，用于对投影数据执行插值计算，以产生与通过使用实际上具有两倍的X射线的测量系统测量的投影数据相当的投影数据， 射线检测器元件作为布置的X射线检测器元件，用于保持参数使用的存储器 d用于计算内插计算装置，以及图像重构器，用于基于由插值计算装置产生的投影数据重建断层图像。

公开(公告)号：US5455425A

公开(公告)日：1995-10-03

申请号：US214757

申请日：1994-03-18

申请人： Shinichi Migita

发明人： Shinichi Migita

IPC分类号： G01T1/185 ,  H01J47/02

CPC分类号： H01J47/02 ,  G01T1/185

摘要： An X-ray detector with a multi-channel type ionization chamber has plural signal plate electrodes and plural high voltage plate electrodes respectively disposed in parallel to and alternating with the signal plate electrodes all of the plate electrodes being mounted between a pair of insulators. A conductive rubber member is provided between one of the insulators and the high voltage plate electrodes, and a long conductive member is provided along the conductive rubber member at a position where the long conductive member contacts the rubber member, but does not contact the high voltage plate electrodes. Thereby, the amount of X-rays is detected accurately in respective channels in spite of the simple construction of the X-ray detector.

摘要翻译： 具有多通道型电离室的X射线检测器具有多个信号板电极和分别设置在信号板电极并与信号板电极交替的多个高压板电极，所有的平板电极安装在一对绝缘体之间。 在一个绝缘体和高压板电极之间设置导电性橡胶部件，在导电性部件与导电性部件接触橡胶部件但不与高电压接触的位置设置有长导体部件 平板电极。 因此，尽管X射线检测器的结构简单，但是在各个通道中准确地检测X射线的量。

公开(公告)号：US5668845A

公开(公告)日：1997-09-16

申请号：US611851

申请日：1996-03-06

申请人： Shinichi Migita

发明人： Shinichi Migita

IPC分类号： A61B6/03 ,  G21K5/10

CPC分类号： A61B6/032 ,  A61B6/4014 ,  G21K5/10

摘要： A computed-tomography apparatus acquires a cross-sectional image of an object from projection data obtained by scanning the object with radiation while rotating a scanner around the object. One of rotation positions of the scanner having a smaller attenuation of radiation is determined. The operation of the scanner is controlled to start the scan from the rotation position having the smaller attenuation. Individual weights are assigned to projection data in a predetermined rotation angle range near a scan start rotation position of the scanner and near a scan end rotation position thereof and projection data in a rotation angle range opposite to the predetermined rotation angle range, respectively. The weighted projection data and unweighted projection data are used for determining corrected data for the entire circumference of the object to generate a cross-sectional image based thereon. The range of a correction region can be changed in accordance with a scan start position so that when the scan start position is not suited in a direction having a smaller attenuation, the correction region is narrowed to optimize the effect of suppression of background noises and artifacts. A plurality of scan start positions can be set on the locus of scan rotation of the scanner so that the actual scan is started from the scan start position which is first detected after the point of time when a scan start signal is given.

摘要翻译： 计算机断层摄影装置通过在围绕物体旋转扫描仪的同时利用辐射扫描物体获得的投影数据来获取物体的横截面图像。 确定具有较小的辐射衰减的扫描仪的旋转位置之一。 控制扫描仪的操作以从具有较小衰减的旋转位置开始扫描。 分别在扫描仪的扫描开始旋转位置附近的预定旋转角度范围内和扫描结束旋转位置附近的投影数据和与预定旋转角度范围相反的旋转角度范围内的投影数据被分配给投影数据。 加权投影数据和未加权投影数据用于确定对象的整个圆周的校正数据，以基于其生成横截面图像。 可以根据扫描开始位置改变校正区域的范围，使得当扫描开始位置不适合具有较小衰减的方向时，校正区域变窄以优化抑制背景噪声和伪像的效果 。 可以在扫描仪的扫描旋转的轨迹上设置多个扫描开始位置，使得从扫描开始位置开始实际扫描，扫描开始位置在给出扫描开始信号的时间点之后首先被检测。