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公开(公告)号：US4780675A
公开(公告)日：1988-10-25
申请号：US85956
申请日：1987-08-14
CPC分类号： G01R33/561
摘要： An incomplete set of magnetic resonance image data is collected and stored in a view memory (40). The incomplete set of image data includes a central or first set of data values (42, 42') and a side or second set of data values (44, 44'). The central data set is operated on by a roll-off filter (64) and a Fourier transform (66) to create a normalized phase map (72). The first and second data sets are Fourier transformed (82) and phase corrected (86) by being multiplied with a complex conjugate (88) of the corresponding phase map data value. A third data set (46, 46') is generated (90) by determining the complex conjugate of the second or side data set. The third data set is Fourier transformed (94) and multiplied (98) by a corresponding value from the phase map to produce a second phase corrected image representation. The first and second phase corrected image representations are summed (100) and stored in a resultant image memory (102).
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公开(公告)号：US4912413A
公开(公告)日：1990-03-27
申请号：US260402
申请日：1988-10-20
IPC分类号： G01R33/54 , G01R33/561 , G01R33/565
CPC分类号： G01R33/54 , G01R33/561 , G01R33/565
摘要： An incomplete set of magnetic resonance image data is collected and stored in a view memory (40). The incomplete set of image data includes a central or first set of data values (42, 42') and half of the remaining data values (44, 44'). A symmetric data set which fills the other remaining half (46, 46') of the data values is generated (90) by determining the complex conjugate of each value of the incomplete data set. The incomplete and symmetric data sets are Fourier transformed (64, 94) to create first and second images f.sub.1 (x,y) and f.sub.2 (x,y). The first and second images are multiplied (100, 104) by conjugately symmetric phase correction values e.sup.i.phi.(x,y) and e.sup.-i.phi.(x,y) from a phase correction memory (70) to produce phase corrected images. The first and second phase corrected image representations are summed (110) and displayed (114). The phase correction values .phi.(x,y) may be derived (68) from the first image or from a phase image (86) derived (80, 82, 84) from a central or other portion of the acquired incomplete image data set.
摘要翻译： 一组不完整的磁共振图像数据被收集并存储在视图存储器（40）中。 不完整的图像数据集合包括中央或第一组数据值（42,42'）和剩余数据值（44,44'）的一半。 通过确定不完整数据集的每个值的复共轭来生成（90）填充数据值的另一半（46,46'）的对称数据集。 不完全和对称的数据集被傅里叶变换（64,94）以产生第一和第二图像f1（x，y）和f2（x，y）。 第一和第二图像通过来自相位校正存储器（70）的共对称相位校正值ei phi（x，y）和e-i phi（x，y）相乘（100,104）以产生相位校正图像。 将第一和第二相位校正图像表示相加（110）并显示（114）。 相位校正值phi（x，y）可以从第一图像或从所获取的不完整图像数据集合的中心部分或其他部分导出（80,82,84）的相位图像（86）导出（68）。
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公开(公告)号：US4851779A
公开(公告)日：1989-07-25
申请号：US157972
申请日：1988-02-18
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。
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公开(公告)号：US4833407A
公开(公告)日：1989-05-23
申请号：US124040
申请日：1987-11-23
IPC分类号： A61B10/00 , A61B5/055 , G01R33/44 , G01R33/48 , G01R33/50 , G01R33/54 , G01R33/56 , G01R33/561
CPC分类号： G01R33/56 , G01R33/561 , G01R33/5602
摘要： A spin echo (52) and a gradient echo (60) are generated in each magnetic resonance sequence repetition. The spin echo is phase encoded by a phase encode gradient (44) in regular steps spanning about a quarter of k-space. More particularly, steps from -n to G.sub.max /2, where n is a small integer and G.sub.max is the maximum phase encode gradient. An off-set phase encode gradient (58) shifts the phase encoding of the gradient echo by G.sub.max /2 relative to the first phase encoding gradient. Data to fill the empty portions of k-space (142, 167) between -n and -G.sub.max are generated from the complex conjugate (140, 160), of the first echo data (74) and the second echo data (76). The first and second echo data and the complex conjugate data are transformed (122, 132, 146, 166) to generate parted image representations (124, 134, 148, 168). The first echo image representation and the corresponding conjugately symmetric image representation are phase corrected (126, 150) in accordance with a phase map ( 112) derived from the central most first echo data (78). The partial image representations are summed (170) to produce a resultant image representation (172).
摘要翻译： 在每个磁共振序列重复中产生自旋回波（52）和梯度回波（60）。 自旋回波由相位编码梯度（44）进行相位编码，其规则步长约为四分之一的k空间。 更具体地，从-n到Gmax / 2的步骤，其中n是小整数，Gmax是最大相位编码梯度。 偏移相位编码梯度（58）相对于第一相位编码梯度将梯度回波的相位编码移位Gmax / 2。 从第一回波数据（74）和第二回波数据（76）的复共轭（140,160）生成-n和-Gmax之间的填充k空间（142,167）的空部分的数据。 第一和第二回波数据和复共轭数据被变换（122,132,146,166）以产生分离的图像表示（124,134,148,168）。 根据从中央最初回波数据（78）得到的相位图（112），第一回波图像表示和对应的共同对称图像表示被相位校正（126,150）。 将部分图像表示相加（170）以产生所得到的图像表示（172）。
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公开(公告)号：US4881033A
公开(公告)日：1989-11-14
申请号：US331750
申请日：1989-04-03
CPC分类号： G01R33/5602 , G01R33/482 , G01R33/5608 , G01R33/56554
摘要： A multi-echo magnetic resonance imaging sequence is implemented such that a radio frequency receiver (34) receives magnetic resonance signals during each of a plurality of magnetic resonance echoes. The resonance data received during each echo are digitized and the resultant echo data are stored in a corresponding echo memory (40, 42). The locations of the data within the memories are brought into registration (52) such that corresponding data in each memory is disposed at the same memory address. Because data from later echoes tends to be weaker or at a lower magnitude, the magnitude of the data stored in each memory is normalized (60). The phase of the data in each memory is brought into coordination by a zero order phase correction (70). A high pass filter (84) and a complementary low pass filter (86) separate complementary portions of the data from the memories. The separated portions are combined into a single synthesizied data set for storage in memory (82). The syntheized data are Fourier transformed (100) to produce a synthetic image which has selected characteristics of an early echo image, e.g. high resolution, and selected characteristics of a late echo image, e.g. good T2 contrast. In this manner, the synthetic image has properties or characteristics which render it more diagnostically valuable than either an early or late echo image.
摘要翻译： 实现多回波磁共振成像序列，使得射频接收器（34）在多个磁共振回波中的每一个期间接收磁共振信号。 在每个回波期间接收到的共振数据被数字化，并且所得到的回波数据被存储在对应的回波存储器（40,42）中。 将存储器内的数据的位置进行注册（52），使得每个存储器中的对应数据被布置在相同的存储器地址处。 因为来自后期回波的数据趋向于较弱或处于较低幅度，所以存储在每个存储器中的数据的幅度被归一化（60）。 通过零阶相位校正（70）使每个存储器中的数据的相位协调。 高通滤波器（84）和互补低通滤波器（86）将数据与存储器的互补部分分开。 分离的部分被组合成单个合成的数据集合以存储在存储器（82）中。 合成数据经傅里叶变换（100）以产生合成图像，该合成图像选择早期回波图像的特征，例如， 高分辨率和晚期回波图像的选定特征，例如。 良好的T2对比度。 以这种方式，合成图像具有使其比早期或晚期回波图像更具诊断价值的性质或特征。
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公开(公告)号：US4920318A
公开(公告)日：1990-04-24
申请号：US252819
申请日：1988-10-03
IPC分类号： G01R33/34 , G01R33/341 , G01R33/36
CPC分类号： G01R33/3628 , G01R33/34046 , G01R33/341 , G01R33/34007 , G01R33/34084 , G01R33/3657
摘要： A resonance exciting coil (C) excites magnetic resonance in nuclei disposed in an image region in which a main magnetic field and transverse gradients have been produced. A flexible receiving coil (D) includes a flexible plastic sheet (40) on which one or more loops (20) are adhered to receive signals from the resonating nuclei. Velcro straps (46) strap the flexible sheet and the attached coil into close conformity with the surface of the portion of the patient to be imaged. An impedance matching or coil resonant frequency adjusting network (50) is mounted on the flexible sheet for selectively adjusting at least one of an impedance match and the peak sensitivity resonant frequency of the receiving coil. A preamplifier (52) amplifies the received signals prior to transmission on a cable (24). A selectively variable voltage source (70) applies a selectively adjustable DC bias voltage to the cable for selectively adjusting at least one of the impedance match and the LC resonant frequency of the receiving coil. The received signals are amplified by an amplifier (82) and processed by an image processor (30) to form man-readable images of the examined region of the patient for display on a video display (32) or the like.
摘要翻译： 共振励磁线圈（C）在设置在已经产生主磁场和横向梯度的图像区域中的核中激发磁共振。 柔性接收线圈（D）包括柔性塑料片（40），一个或多个环（20）粘附在柔性塑料片上以接收来自谐振核的信号。 魔术贴带（46）将柔性片材和附接的线圈绑定成与待成像的患者部分的表面紧密一致。 阻抗匹配或线圈共振频率调整网络（50）安装在柔性片上，用于选择性地调节接收线圈的阻抗匹配和峰值灵敏度谐振频率中的至少一个。 前置放大器（52）在电缆（24）上传输之前放大所接收的信号。 选择性可变电压源（70）向电缆施加选择性可调节的直流偏置电压，用于选择性地调节接收线圈的阻抗匹配和LC谐振频率中的至少一个。 所接收的信号由放大器（82）放大并由图像处理器（30）处理，以形成用于在视频显示器（32）等上显示的被检查区域的人可读图像。
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公开(公告)号：US4797617A
公开(公告)日：1989-01-10
申请号：US933152
申请日：1986-11-21
申请人： George J. Misic , Aarne Lillo , John L. Patrick , G. Neil Holland
发明人： George J. Misic , Aarne Lillo , John L. Patrick , G. Neil Holland
CPC分类号： G01R33/34046 , G01R33/34007 , G01R33/3628 , G01R33/3657
摘要： A nuclear magnetic resonance radio frequency coil. The disclosed coil provides high frequency resonance signals for perturbing a magnetic field within the coil. The coil is impedance matched and tuned with adjustable capacitors. A balanced configuration is achieved with a co-axial cable chosen to phase shift an energization signal coupled to the coil. The preferred coil is a thin metallic foil having a shorting conductor, four wing conductors, and uniquely shaped parallel cross conductors connecting the shorting and wing conductors. When mounted to an rf transmissive plastic substrate and energized the coil produces a homogenous field within a region of interest the size of a patient head. A semicircular balanced feedbar arrangement is used to minimize undesired field contributions.
摘要翻译： 核磁共振射频线圈。 所公开的线圈提供用于扰乱线圈内的磁场的高频谐振信号。 线圈阻抗匹配并用可调电容器调谐。 使用同轴电缆实现平衡配置，以使相耦合到线圈的通电信号相移。 优选的线圈是具有短路导体，四个机翼导体和连接短路和翼导体的独特成形的平行十字导体的薄金属箔。 当安装到rf透射塑料基板并通电时，线圈在患者头部的尺寸的感兴趣区域内产生均匀的场。 使用半圆平衡馈线布置来最小化不期望的场贡献。
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公开(公告)号：US4839594A
公开(公告)日：1989-06-13
申请号：US120475
申请日：1987-11-13
CPC分类号： G01R33/3621 , G01R33/34046 , G01R33/341 , G01R33/3628
摘要： Magnet (12) creates a main magnetic field along a z-axis through an image region. A localized coil (D) is disposed in the image region at least to receive magnetic resonance signals from nuclei of the subject which have been induced to resonance. The localized coil includes an inner conductor (30), an outer conductor (32), and a dielectric material (52) therebetween. The outer conductor defines a gap (50) midway between its ends. One end of the inner conductor is connected with a gate of an FET transistor (66) and the outer conductor is connected with its source. The transistor source and drain are connected by a coaxial transmission cable (38) with a DC power supply (70) which provides a DC bias across the transistor source and drain. The cable also connects the transistor with a radio frequency receiver (40) to convey preamplified magnetic resonance signals thereto. The other end of the inner conductor may be connected with the outer conductor to provide an unbalanced localized coil or the ends may each be connected with an FET transistor (66a, 66 b) in a balanced coil arrangement (FIG. 9).
摘要翻译： 磁体（12）通过图像区域沿z轴产生主磁场。 至少在图像区域中设置局部线圈（D）以接收已经被诱导到共振的受试者的核的磁共振信号。 局部线圈包括内部导体（30），外部导体（32）和介电材料（52）。 外导体在其端部之间的中间限定间隙（50）。 内部导体的一端与FET晶体管（66）的栅极连接，外部导体与其源极连接。 晶体管源极和漏极由具有直流电源（70）的同轴传输电缆（38）连接，直流电源（70）在晶体管源极和漏极之间提供直流偏置。 电缆还将晶体管与射频接收器（40）连接，以将预放大的磁共振信号传送到其上。 内部导体的另一端可以与外部导体连接以提供不平衡的局部线圈，或者各个端子可以以平衡线圈装置（图9）与FET晶体管（66a，66b）连接。
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公开(公告)号：US4793356A
公开(公告)日：1988-12-27
申请号：US765708
申请日：1985-08-14
IPC分类号： A61B5/055 , A61B10/00 , G01R33/341 , G01R33/36 , G01R33/44 , G01R33/48 , H01F6/06 , A61B5/05
CPC分类号： G01R33/3628 , G01R33/341
摘要： A resonance exciting coil (C) excites magnetic resonance in nuclei disposed in an image region in which a main magnetic field and transverse gradients have been produced. A flexible receiving coil (D) includes a flexible plastic sheet (40) on which one or more loops (20) are adhered to receive signals from the resonating nuclei. Velcro straps (46) strap the flexible sheet and the attached coil into close conformity with the surface of the portion of the patient to be imaged. An impedance matching or coil resonant frequency adjusting network (50) is mounted on the flexible sheet for selectively adjusting at least one of an impedance match and the peak sensitivity resonant frequency of the receiving coil. A preamplifier (52) amplifies the received signals prior to transmission on a cable (24). A selectively variable voltage source (70) applies a selectively adjustable DC bias voltage to the cable for selectively adjusting at least one of the impedance match and the LC resonant frequency of the receiving coil. The received signals are amplified by an amplifier (82) and processed by an image processor (30) to form man-readable images of the examined region of the patient for display on a video display (32) or the like.
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公开(公告)号：US4634980A
公开(公告)日：1987-01-06
申请号：US641570
申请日：1984-08-16
申请人： George J. Misic , Aarne Lillo , John L. Patrick , G. Neil Holland
发明人： George J. Misic , Aarne Lillo , John L. Patrick , G. Neil Holland
CPC分类号： G01R33/34007 , G01R33/34046 , G01R33/3628 , G01R33/3657
摘要： A nuclear magnetic resonance radio frequency coil. The disclosed coil provides high frequency resonance signals for perturbing a magnetic field within the coil. The coil is impedance matched and tuned with adjustable capacitors. A balanced configuration is achieved with a co-axial cable chosen to phase shift an energization signal coupled to the coil. The preferred coil is a thin metallic foil having a shorting conductor, four wing conductors, and uniquely shaped parallel cross conductors connecting the shorting and wing conductors. When mounted to a rf transmissive plastic substrate and energized the coil produces a homogeneous field within a region of interest the size of a patient head. A semicircular balanced feedbar arrangement is used to minimize undesired field contributions.
摘要翻译： 核磁共振射频线圈。 所公开的线圈提供用于扰乱线圈内的磁场的高频谐振信号。 线圈阻抗匹配并用可调电容器调谐。 使用同轴电缆实现平衡配置，以使相耦合到线圈的通电信号相移。 优选的线圈是具有短路导体，四个机翼导体和连接短路和翼导体的独特成形的平行十字导体的薄金属箔。 当安装到rf透射塑料基板并通电时，线圈在患者头部的尺寸的感兴趣区域内产生均匀的场。 使用半圆平衡馈线布置来最小化不期望的场贡献。
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