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公开(公告)号：US06201393B1
公开(公告)日：2001-03-13
申请号：US08990651
申请日：1997-12-15
IPC分类号： G01V300
CPC分类号： G01R33/56308 , G01R33/4835 , G01R33/56509
摘要： An MRI system acquires MRA data from two overlapping thin slabs using a 3DTOF pulse sequence. Motion artifacts are reduced by using a reverse centric phase encode order during the first thin slab acquisition and a centric phase encode order during the second thin slab acquisition. Patient movement is reduced by producing a uniform sound with gradient pulse sequences during the interval between thin slab acquisitions and during a preparation period prior to the first thin slab acquisition.
摘要翻译： MRI系统使用3DTOF脉冲序列从两个重叠的薄板获取MRA数据。 在第一薄板采集期间使用反向中心相位编码顺序并在第二薄板采集期间以中心相位编码顺序减少运动伪影。 通过在薄板获得之间的间隔期间和在第一薄板获取之前的准备阶段期间产生具有梯度脉冲序列的均匀声音来减少患者运动。
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2.发明授权Method for reducing image artifacts caused by patient motion during MR imaging 失效用于减少MR成像期间患者运动引起的图像伪像的方法公开(公告)号：US06288544B1
公开(公告)日：2001-09-11
申请号：US09552177
申请日：2000-04-18
IPC分类号： G01V300
CPC分类号： G01R33/56308 , G01R33/4835 , G01R33/56509
摘要： An MRI system acquires MRA data from two overlapping thin slabs using a 3DTOF pulse sequence. Motion artifacts are reduced by using a reverse centric phase encode order during the first thin slab acquisition and a centric phase encode order during the second thin slab acquisition. Patient movement is reduced by producing a uniform sound with gradient pulse sequences during the interval between thin slab acquisitions and during a preparation period prior to the first thin slab acquisition.
摘要翻译： MRI系统使用3DTOF脉冲序列从两个重叠的薄板获取MRA数据。 在第一薄板采集期间使用反向中心相位编码顺序并在第二薄板采集期间以中心相位编码顺序减少运动伪影。 通过在薄板获得之间的间隔期间和在第一薄板获取之前的准备阶段期间产生具有梯度脉冲序列的均匀声音来减少患者运动。
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3.发明授权公开(公告)号：US10048338B2
公开(公告)日：2018-08-14
申请号：US14694621
申请日：2015-04-23
IPC分类号： G01R33/48 , G01R33/561
摘要： Systems and methods for efficiently generating MR images are provided. The method comprises acquiring k-space MR data, reconstructing an MR image from the k-space MR data, and generating the MR image. The MR image is reconstructed using an alternative-direction-method-of-multiplier (ADMM) strategy that decomposes an optimization problem into subproblems, and at least one of the subproblems is further decomposed into small problems. The further decomposition is based on Woodbury matrix identity and uses a diagonal preconditioner based on non-Toeplitz models.
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4.发明授权Method of performing magnetic resonance angiography using two-dimensional imaging and de-rated gradients 有权使用二维成像和降额梯度进行磁共振血管造影的方法公开(公告)号：US06259940B1
公开(公告)日：2001-07-10
申请号：US09301246
申请日：1999-04-28
IPC分类号： A61B5055
CPC分类号： G01R33/5635 , G01R33/56308 , G01R33/56518 , G01R33/56581
摘要： In an MRI system using high-performance gradient hardware, a method includes de-rating selected lobes in a 2DTOF imaging pulse sequence; employing images from the two-dimensional imagery to detect the presence of disease; and performing three-dimensional contrast-enhanced MRA if disease was detected at a sufficiently high level to make three-dimensional imaging useful. By de-rating selected lobes of the 2DTOF imaging pulse sequence, sensitivity to carotid stenosis at or above the clinically important range of 60-70% is achieved.
摘要翻译： 在使用高性能梯度硬件的MRI系统中，一种方法包括以2DTOF成像脉冲序列降低所选择的瓣; 使用二维图像的图像来检测疾病的存在; 并且如果在足够高的水平检测到疾病以使三维成像有用，则执行三维造影增强MRA。 通过降低2DTOF成像脉冲序列的选定的瓣膜，实现了临床上重要范围为60-70％之间的颈动脉狭窄的敏感性。
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公开(公告)号：US06175236B1
公开(公告)日：2001-01-16
申请号：US09047822
申请日：1998-03-25
IPC分类号： G01V300
CPC分类号： G01R33/446 , G01R33/5613
摘要： A method for acquiring spatially and spectrally selective MR images by means of an MR imaging system includes the step of selecting an SPSP pulse sequence, comprising a succession of RF sub-pulses and an oscillatory gradient magnetic field, which is disposed to select a slice through a subject. The method further includes measuring specified parameters of a perturbation magnetic field associated with the imaging system, and deriving an expression for the perturbation field from respective measured parameters and from the oscillatory gradient magnetic field. A specified ideal frequency modulation function, associated with the SPSP sequence, is disposed to offset the slice to a particular spatially localized region of the subject. The SPSP pulse sequence is modified by adjusting the frequency modulation function in specified corresponding relationship with the expression. The modified SPSP pulse sequence is then applied to the subject to excite a selected spectral species in the spatially localized region, while substantially reducing signal intensity loss resulting from the perturbation magnetic field.
摘要翻译： 用于通过MR成像系统获取空间和频谱选择性MR图像的方法包括选择包括一系列RF子脉冲和振荡梯度磁场的SPSP脉冲序列的步骤，其被设置为选择切片通过 课程。 该方法还包括测量与成像系统相关联的扰动磁场的指定参数，以及从相应的测量参数和振荡梯度磁场导出扰动场的表达式。 设置与SPSP序列相关联的指定的理想频率调制功能，以将切片偏移到对象的特定空间局部区域。 通过调整与规定的对应关系的频率调制函数来修改SPSP脉冲序列。 然后将经修改的SPSP脉冲序列应用于受试者以激发空间局部区域中的选定光谱物种，同时显着降低由扰动磁场引起的信号强度损失。
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公开(公告)号：US5435303A
公开(公告)日：1995-07-25
申请号：US263573
申请日：1994-06-23
IPC分类号： A61B5/055 , G01R33/567
CPC分类号： A61B5/0555 , G01R33/4818 , G01R33/5673
摘要： Flow encoded NMR pulse sequences are employed to acquire data sets from which a set of angiographic images can be reconstructed depicting blood flow at successive phases during the cardiac cycle. The number of angiographic images is increased by selecting views from adjacent data sets to form interpolated data sets that are employed to reconstruct angiographic images depicting blood flow at cardiac phases between the successive phases.
摘要翻译： 采用流动编码的NMR脉冲序列来获取数据集，从该数据集可以重建一组血管造影图像，描绘在心动周期期间连续相位的血流量。 通过从相邻数据集中选择视图来增加血管造影图像的数量，以形成用于重建描绘连续相之间的心脏相位的血流的血管造影图像的内插数据集。
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公开(公告)号：US5339035A
公开(公告)日：1994-08-16
申请号：US57940
申请日：1993-05-07
IPC分类号： G01R33/483 , G01R33/54 , G01R33/563 , G01R33/20
CPC分类号： G01R33/482 , G01R33/563 , G01R33/5605
摘要： An NMR scanner performs a series of pulse sequences from which NMR data is acquired and used to reconstruct an image. Image contrast is enhanced by magnetization transfer from short-T.sub.2 spin species that are saturated by an off-resonance, substantially rectangular shaped RF saturation pulse applied during each pulse sequence.
摘要翻译： NMR扫描仪执行一系列脉冲序列，从中获取NMR数据并用于重建图像。 通过在每个脉冲序列期间施加的偏共振，基本上矩形的RF饱和脉冲饱和的短T2自旋物种的磁化转移来增强图像对比度。
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8.发明申请Systems and Methods for Efficiently Generating Magnetic Resonance Images from Incomplete Data 审中-公开从不完整的数据有效地产生磁共振图像的系统和方法公开(公告)号：US20150309136A1
公开(公告)日：2015-10-29
申请号：US14694621
申请日：2015-04-23
IPC分类号： G01R33/48 , G01R33/36 , G01R33/561 , G01R33/385 , G01R33/56
CPC分类号： G01R33/4826 , G01R33/5611
摘要： Systems and methods for efficiently generating MR images are provided. The method comprises acquiring k-space MR data, reconstructing an MR image from the k-space MR data, and generating the MR image. The MR image is reconstructed using an alternative-direction-method-of-multiplier (ADMM) strategy that decomposes an optimization problem into subproblems, and at least one of the subproblems is further decomposed into small problems. The further decomposition is based on Woodbury matrix identity and uses a diagonal preconditioner based on non-Toeplitz models.
摘要翻译： 提供了有效产生MR图像的系统和方法。 该方法包括获取k空间MR数据，从k空间MR数据重建MR图像，以及生成MR图像。 使用将优化问题分解为子问题的替代方向乘法器（ADMM）策略重构MR图像，并且至少一个子问题进一步分解为小问题。 进一步分解是基于Woodbury矩阵身份，并使用基于非Toeplitz模型的对角预处理器。
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公开(公告)号：US06518759B2
公开(公告)日：2003-02-11
申请号：US09829238
申请日：2001-04-09
申请人： Matthew A. Bernstein
发明人： Matthew A. Bernstein
IPC分类号： G01V300
CPC分类号： G01R33/54
摘要： A CE-MIRA image is acquired using a centric view order. The acquired k-space data set is motion corrected by reconstructing tracking images from successive annular segments of k-space data and detecting the location of a point spread object therein. Each k-space data segment is phase corrected to align the point spread object with a reference position.
摘要翻译： 以中心视图顺序获取CE-MIRA图像。 所获取的k空间数据集通过从k空间数据的连续环形段重建跟踪图像并检测其中的点扩展对象的位置而进行运动校正。 每个k空间数据段被相位校正，以使点扩展对象与参考位置对齐。
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公开(公告)号：US6135954A
公开(公告)日：2000-10-24
申请号：US118411
申请日：1998-07-17
摘要： A method of peripheral MR angiography is provided for imaging an artery or other vessel, wherein the vessel is of such length that MR data must be acquired at each of a plurality of scan stations spaced along the vessel. In accordance with the method, a contrast agent is intravenously injected, in order to provide a bolus which successively flows to each of the scan stations. After acquiring an initial subset of the MR data associated with a given scan station, the bolus is tracked to determine whether it has arrived at the next-following scan station. If so, at least some of the MR data associated with the next scan station are then acquired. However, if it is found that the bolus has not yet arrived at the next scan station, acquisition of further data at the given scan station is continued.
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