公开(公告)号：US5073752A

公开(公告)日：1991-12-17

申请号：US510981

申请日：1990-04-19

申请人： Gordon D. DeMeester ,  Kenneth S. Denison ,  Francis H. Bearden

发明人： Gordon D. DeMeester ,  Kenneth S. Denison ,  Francis H. Bearden

IPC分类号： A61B5/055 ,  G01R33/48 ,  G01R33/54 ,  G01R33/56 ,  G06F17/14 ,  G06T1/00

CPC分类号： G01R33/56

摘要： Magnetic resonance imaging data lines or views are generated and stored in a magnetic resonance data memory (56). The number of views or phase encode gradient steps N along each of one or more phase encode gradient directions is selected (70) to match the dimensions of the region of interest. A discrete Fourier transform algorithm (94) operates on the data in the magnetic resonance data memory to generate an image representation for storage in an image memory (96). Unlike a fast Fourier transform algorithm which requires a.sup.N views or data lines, where a and N are integers, the discrete Fourier transform has a flexible number of data lines and data values which can be accommodated. More specifically to the preferred embodiment, the discrete Fourier transform operation is performed by a CHIRP-Z transform or a Goertzel's second order Z-transform which can accommodate any number of data lines or values.

公开(公告)号：US4851779A

公开(公告)日：1989-07-25

申请号：US157972

申请日：1988-02-18

申请人： Gordon D. DeMeester ,  G. Neil Holland ,  Francis H. Bearden

发明人： Gordon D. DeMeester ,  G. Neil Holland ,  Francis H. Bearden

IPC分类号： G01R33/54 ,  A61B5/055 ,  G01R33/44 ,  G01R33/48 ,  G01R33/561 ,  G01R33/565

CPC分类号： G01R33/56545 ,  G01R33/561

摘要： An incomplete set of three dimensional magnetic resonance data is collected and stored in acquired data memory (40). The incomplete data set is complete with respect to first and second directions and incomplete with respect to a third direction. However, the acquired data set has data along the third direction between .+-.n central values and half the remaining values. One dimensional inverse Fourier transforms (64, 66) are performed with respect to the first and second directions to create an intermediate data set (68). A phase correction array or plurality of phase correction vectors p(r) are generated from the intermediate data and stored in a phase correction memory (82). A symmetric data set (100) is created as the complex conjugate of the intermediate data set. The intermediate and symmetric data sets are one dimensionally inverse Fourier transformed (96, 104) with respect to the third direction one vector at a time to produce vectors of first and second complex image arrays (f.sub.A, f.sub.S) corrected (96, 108) with the corresponding phase correction vector, and combined (110) into a line of a resultant three dimensional image representation (112).

摘要翻译： 收集不完整的一组三维磁共振数据并将其存储在所获取的数据存储器（40）中。 不完整的数据集相对于第一和第二方向是完整的，并且相对于第三方向是不完整的。 然而，所获取的数据集具有+/- n个中心值和剩余值的一半之间沿着第三方向的数据。 相对于第一和第二方向执行一维傅里叶逆变换（64,66）以创建中间数据集（68）。 相位校正阵列或多个相位校正矢量p（r）从中间数据生成并存储在相位校正存储器（82）中。 创建对称数据集（100）作为中间数据集的复共轭。 中间对称数据集和对称数据集一次相对于第三方向一维逆变换（96,104），一次产生一个矢量，以产生校正的第一和第二复数图像阵列（f，f）的向量（96,108） 相应的相位校正矢量，并将其组合（110）到所得到的三维图像表示（112）的一行中。

公开(公告)号：US5825185A

公开(公告)日：1998-10-20

申请号：US757153

申请日：1996-11-27

申请人： Haiying Liu ,  Francis H. Bearden ,  Gordon D. DeMeester

发明人： Haiying Liu ,  Francis H. Bearden ,  Gordon D. DeMeester

IPC分类号： G01R33/48 ,  A61B5/055 ,  G01R33/561 ,  G01R33/565 ,  G01V3/00

CPC分类号： G01R33/56554 ,  G01R33/56545

摘要： A transmitter (24) and gradient amplifiers (20) transmit radio frequency excitation and other pulses to induce magnetic resonance in selected magnetic dipoles and cause the magnetic resonance to be focused into a series of echoes (66) at each of a plurality of preselected echo positions following each excitation. A receiver (38) converts each echo into a data line. Calibration data lines having a close to zero phase-encoding are collected and used to generate correction parameters (102) for each of the echo positions. These parameters include relative echo center positions (96) and unitary complex correction vectors (106). The calibration data lines for each of the preselected positions are one-dimensionally Fourier transformed (82) and multiplied (90) by the same complex conjugate reference echo (80). These data lines are then inverse Fourier transformed (92) to generate an auxiliary data array (94). A relative echo center position is computed (96) which represents a fractional shift of the true center relative to the reference echo. A complex sum is computed (104) from the relative echo center position and normalized (106) to generate a unitary correction vector. The phase-correction parameters are used to phase-correct (116) imaging data lines. The phase-corrected imaging data lines are sorted (122) to build an image plane which is one-dimensionally Fourier transformed (128) in the phase-encoding direction to produce a final corrected image (130) for display on a monitor (134).

摘要翻译： 发射器（24）和梯度放大器（20）发射射频激发和其它脉冲以在选定的磁偶极子中引起磁共振，并使磁共振聚焦成多个预选回波中的每一个的一系列回波（66） 每次激发后的位置。 接收器（38）将每个回波转换成数据线。 收集具有接近零相位编码的校准数据线，并用于为每个回波位置产生校正参数（102）。 这些参数包括相对回波中心位置（96）和单一复数校正向量（106）。 用于每个预选位置的校准数据线通过相同的复共轭参考回波（80）进行一维傅立叶变换（82）并乘以（90）。 这些数据线然后被逆傅里叶变换（92）以产生辅助数据阵列（94）。 计算相对回波中心位置（96），其表示真实中心相对于参考回波的分数偏移。 从相对回波中心位置计算复数和（104）并归一化（106）以产生单位校正向量。 相位校正参数用于相位校正（116）成像数据线。 对相位校正后的成像数据线进行排序（122）以构建在相位编码方向上一维付里叶变换（128）的图像平面，以产生用于在监视器（134）上显示的最终校正图像（130） 。

公开(公告)号：US06486667B1

公开(公告)日：2002-11-26

申请号：US09656620

申请日：2000-09-07

申请人： Dee H. Wu ,  David L. Foxall ,  Francis H. Bearden

发明人： Dee H. Wu ,  David L. Foxall ,  Francis H. Bearden

IPC分类号： G01V300

CPC分类号： G01R33/4835 ,  G01R33/4828 ,  G01R33/50 ,  G01R33/56 ,  G01R33/563

摘要： A method of MRI includes supporting a subject in an examination region of an MRI scanner, and setting up a spin system with a net magnetization. An inversion pulse is applied which inverts the magnetization of the spin system in a selected volume of the subject. As the magnetization re-grows, a first set of raw data is generated by acquiring MR signals from a series of regions within the selected volume. For the first set of raw data, the series of regions are acquired in a first temporal order with respect to the inversion pulse. The inversion pulse is re-applied, and as the magnetization re-grows, a second set of raw data is generated in similar fashion to the first. However, for the second set of raw data, the series of regions are acquired in a second temporal order with respect to the inversion pulse. The second temporal order is different from the first temporal order. From the first and second sets of raw data, respectively, first and second sets of complex image data are generated. A complex phase correction factor is then determined and applied to one of, or both, the first and second sets of complex image data to thereby phase match the same. A combined image is generated via a pixel by pixel complex combination of the phase matched first and second sets of complex image data.

摘要翻译： MRI的一种方法包括在MRI扫描仪的检查区域中支持受试者，并建立具有净磁化强度的自旋系统。 施加反转脉冲，其反转所选择的体积的受试者的旋转系统的磁化。 当磁化重新增长时，通过从所选择的体积内的一系列区域获取MR信号来产生第一组原始数据。 对于第一组原始数据，相对于反转脉冲以第一时间顺序获取一系列区域。 重新施加反转脉冲，随着磁化的增长，第二组原始数据以与第一组相似的方式生成。 然而，对于第二组原始数据，相对于反转脉冲以第二时间顺序获取一系列区域。 第二时间顺序与第一时间顺序不同。 从第一组和第二组原始数据分别，生成第一组和第二组复数图像数据。 然后确定复相位校正因子并将其应用于第一和第二组复数图像数据中的一个或两者，从而使其相位匹配。 通过相位匹配的第一和第二组复数图像数据的逐像素复合组合生成组合图像。

公开(公告)号：US4678996A

公开(公告)日：1987-07-07

申请号：US731509

申请日：1985-05-07

申请人： E. Mark Haacke ,  Francis H. Bearden

发明人： E. Mark Haacke ,  Francis H. Bearden

IPC分类号： A61B10/00 ,  A61B5/055 ,  G01N24/08 ,  G01R33/48 ,  G01R33/561 ,  G01R33/567 ,  G01R33/20

CPC分类号： G01N24/08 ,  G01R33/561 ,  G01R33/5615 ,  G01R33/5616 ,  G01R33/56509 ,  G01R33/5676

摘要： Hybrid fast scan magnetic resonance imaging is performed by using, for example, both a two dimensional Fourier transform (2DFT) method using phase encoding prior to data collection and an echo planar technique which phase encodes by using an oscillating gradient during data collection. In this hybrid imaging, the amplitude of the oscillating gradient determines the time savings achieved in imaging. The hybrid scan has particular application for medical diagnostic imaging since it is advantageous that such imaging be conducted as rapidly as possible.

摘要翻译： 通过使用例如在数据收集之前使用相位编码的二维傅里叶变换（2DFT）方法和在数据收集期间通过使用振荡梯度进行相位编码的回波平面技术来执行混合快速扫描磁共振成像。 在这种混合成像中，振荡梯度的振幅决定了成像中实现的时间节省。 混合扫描具有用于医疗诊断成像的特殊应用，因为有利的是，尽可能快地进行这种成像。

公开(公告)号：US06411089B1

公开(公告)日：2002-06-25

申请号：US09718747

申请日：2000-11-22

申请人： Christopher K. Anand ,  Paul M. Margosian ,  Francis H. Bearden

发明人： Christopher K. Anand ,  Paul M. Margosian ,  Francis H. Bearden

IPC分类号： G01V300

CPC分类号： G01R33/54

摘要： A non-rectangular central kernel (200, 400, 500) of magnetic resonance image data is collected and stored in an acquired data memory (44). A non-rectangular peripheral portion (210, 410, 510) of magnetic resonance image data adjacent the central kernel (200) is collected and stored in the acquired data memory (44). A phase correction data value set (54) is generated from at least a portion of the central and peripheral data value sets. A synthetic conjugately symmetric data set (220, 420, 520) is generated (60) from the peripheral data set and phase corrected (60) using the phase correction data value set (54). Unsampled corners of k-space are zero filled. The central, peripheral, and conjugately symmetric data sets are combined (80) to form a combined data set. The combined data'set is Fourier transformed (82) to form an intermediate image representation (84), which may be exported for display (90) or used for a further iteration. In this manner, a significant amount of data in a central region of k-space that contributes most strongly to the resultant image is collected while significantly reducing data acquisition time.

摘要翻译： 将磁共振图像数据的非矩形中心核心（200,400,500）收集并存储在获取的数据存储器（44）中。 与中央核（200）相邻的磁共振图像数据的非矩形周边部分（210,410,510）被收集并存储在获取的数据存储器（44）中。 从中央和外围数据值集合的至少一部分生成相位校正数据值集合（54）。 使用相位校正数据值集合（54）从外围数据集（60）生成合成对称数据集（220,420,520）并进行相位校正（60）。 k空间的未采样角是零填充。 组合中央，外围和共同对称的数据集（80）以形成组合数据集。 组合数据集被傅立叶变换（82）以形成中间图像表示（84），其可以被输出用于显示（90）或用于进一步的迭代。 以这种方式，在显着减少数据采集时间的同时，收集对结果图像贡献最大的k空间的中心区域中的大量数据。

公开(公告)号：US06313629B1

公开(公告)日：2001-11-06

申请号：US09444609

申请日：1999-11-23

申请人： Xecheng Liu ,  Francis H. Bearden

发明人： Xecheng Liu ,  Francis H. Bearden

IPC分类号： G01V300

CPC分类号： G01R33/58

摘要： A method of magnetic resonance imaging includes subjecting a number of regions of an object being imaged to a magnetic resonance calibration pulse sequence. Each calibration pulse sequence generates a single calibration echo. Each of the calibration echoes are collected and therefrom correction factors are generated. Thereafter, the method includes subjecting the regions of the object being imaged to a plurality of magnetic resonance imaging pulse sequences. Each of the imaging pulse sequences generates a single imaging echo. Each imaging echo is collected into k-space as a plurality of sampled data points. The plurality of sampled data points are adjusted in accordance with the correction factors as each imaging echo is collected into k-space.

摘要翻译： 磁共振成像的方法包括使成像对象的多个区域经受磁共振校准脉冲序列。 每个校准脉冲序列产生单个校准回波。 收集每个校准回波，并产生校正因子。 此后，该方法包括使被成像物体的区域经受多个磁共振成像脉冲序列。 每个成像脉冲序列产生单个成像回波。 每个成像回波作为多个采样数据点被收集到k空间中。 当每个成像回波被收集到k空间中时，根据校正因子来调整多个采样数据点。