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公开(公告)号：US06377831B1
公开(公告)日：2002-04-23
申请号：US09449432
申请日：1999-11-24
IPC分类号： A61B505
CPC分类号： G01R33/56308 , A61B5/055 , G01R33/56
摘要： A system and method for creating MR images using mask data that is copied forward for on-the-fly image subtraction for use within such techniques as MR angiography is disclosed. The invention includes acquiring an MR mask image comprised of a plurality of k-space lines, and then copying the k-space line data of the MR mask image into a number of different memory locations. The number of different memory locations corresponds to a preselected number of MR image acquisitions as set by an MR operator. The invention next includes acquiring the preselected number of MR images, each comprised of k-space line data. As the k-space line data is acquired, it is then immediately accumulated in one of the memory locations having the MR mask image k-space line data. By setting a polarity of the data stored, each acquired k-space line of an acquired MR image is subtracted from a corresponding k-space line of the MR mask image in real time. The image is then reconstructed using the subtracted k-space line data. After each additional MR image acquisition, the data is accumulated with the masked data, which result is used for reconstructing an MR image without the need to transfer the data to another workstation for separate processing or post-processing. In this manner, the acquired data is automatically subtracted on-the-fly, thereby yielding fluoroscopic images, for example, without the prior art penalties of excessive image reconstruction time and image post-processing time.
摘要翻译： 公开了一种用于使用向前复制的掩模数据创建MR图像的系统和方法，用于在例如MR血管造影术的诸如MR血管造影术的技术中使用的即时图像减法。 本发明包括获取由多个k空间线组成的MR掩模图像，然后将MR掩模图像的k空间线数据复制到多个不同的存储器位置。 不同存储器位置的数量对应于由MR操作器设置的预选数量的MR图像采集。 本发明接下来包括获取每个由k空间线数据组成的预选数量的MR图像。 当获取k空间线数据时，它立即被积累在具有MR掩模图像k空间线数据的存储器位置之一中。 通过设置存储的数据的极性，实时地从MR掩模图像的相应的k空间线中减去获取的MR图像的每个获取的k空间线。 然后使用减去的k空间线数据重建图像。 在每次额外的MR图像采集之后，数据用掩蔽的数据累加，这个结果用于重建MR图像，而不需要将数据传送到另一个工作站进行单独的处理或后处理。 以这种方式，所获取的数据被自动减去，从而产生荧光透视图像，例如，没有现有技术对过度图像重建时间和图像后处理时间的惩罚。
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公开(公告)号：US06889071B2
公开(公告)日：2005-05-03
申请号：US09681068
申请日：2000-12-19
IPC分类号： G01R33/48 , A61B5/055 , G01R33/567 , A61B5/05
CPC分类号： G01R33/567
摘要： A system and method are disclosed to acquire high temporal resolution free-breathing cardiac MR images. The technique includes monitoring heart rate of a patient just prior to image acquisition to acquire a time period of an R—R interval, and using this time period from the heart rate monitoring to prospectively estimate future R—R intervals. The acquisition of MR data can then commence at any point in an R—R interval and extend for the time period recorded. The data acquisition can be segmented and acquired in successive R—R intervals, then combined to create high temporal resolution images.
摘要翻译： 公开了一种获得高时间分辨率自由呼吸心脏MR图像的系统和方法。 该技术包括在图像获取之前监测患者的心率以获取R-R间期的时间段，并且使用来自心率监测的该时间段来前瞻性地估计未来的R-R间期。 然后可以在R-R间隔中的任何点开始获取MR数据，并延长记录的时间段。 可以在连续的R-R间隔中对数据采集进行分段和采集，然后组合以创建高时间分辨率图像。
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公开(公告)号：US08165377B2
公开(公告)日：2012-04-24
申请号：US12323594
申请日：2008-11-26
申请人： Vivek Vaidya , Rakesh Mullick , Shekhar Dwivedi , Thomas K. F. Foo , Christopher Judson Hardy , Daniel James Blezek , Umesha Perdoor Srinivas Adiga
发明人： Vivek Vaidya , Rakesh Mullick , Shekhar Dwivedi , Thomas K. F. Foo , Christopher Judson Hardy , Daniel James Blezek , Umesha Perdoor Srinivas Adiga
CPC分类号： A61B5/055 , A61B5/0037 , A61B6/032 , A61B6/503 , A61B8/14 , G06T7/75 , G06T2207/10088 , G06T2207/30048
摘要： An apparatus, system and method to determine a coordinate system of a heart includes an imager and a computer. The computer is programmed to acquire a first set of initialization imaging data from an anatomical region of a free-breathing subject. A portion of the first set of initialization imaging data includes organ data, which includes cardiac data. The computer is further programmed to determine a location of a central region of a left ventricle of a heart, where the location is based on the organ data and a priori information. The computer is also programmed to determine a short axis of the left ventricle based on the determined location, acquire a first set of post-initialization imaging data from the free-breathing subject from an imaging plane orientation based on the determination of the short axis, and reconstruct at least one image from the first set of post-initialization imaging data.
摘要翻译： 用于确定心脏坐标系的装置，系统和方法包括成像器和计算机。 计算机被编程为从自由呼吸对象的解剖区域获取第一组初始化成像数据。 第一组初始化成像数据的一部分包括包括心脏数据的器官数据。 计算机还被编程为确定心脏左心室的中心区域的位置，其中位置基于器官数据和先验信息。 计算机还被编程为基于确定的位置来确定左心室的短轴，基于短轴的确定，从成像平面取向获取来自自由呼吸对象的第一组初始初始化后成像数据， 并且从所述第一组初始化后成像数据重建至少一个图像。
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4.发明授权Method and apparatus for MR perfusion image acquisition using a notched RF saturation pulse 有权使用缺口RF饱和脉冲进行MR灌注图像采集的方法和装置公开(公告)号：US06618605B1
公开(公告)日：2003-09-09
申请号：US09391965
申请日：1999-09-08
IPC分类号： A61B5055
CPC分类号： G01R33/56341 , G01R33/4838
摘要： A method and apparatus is disclosed for MR perfusion acquisition using a notched RF saturation pulse. In acquiring such MR data, a volume of slice locations is selected in which MR data is to be acquired. Each given slice is prepared with a notched RF saturation pulse which has a stop-band between a pair of pass-bands. The stop-band is designed to not affect the spins in the next slice in which MR data is to be acquired thereby effectively increasing the TI and increasing SNR and contrast simultaneously. Since the notched saturation pulse saturates all the spins outside of the notched stop-band, the blood in the ventricular chamber is effectively saturated so that the resulting perfusion images have blood pool suppression. Additionally, the use of a 90° presaturation RF pulse provides a high level of immunity to the effects of arrhythmias or other variations in the patient's heart rate. In order to keep the stop-band, or the notch, as wide as possible to overlap the boundaries of each slice location, it is preferable to interleave the acquisition of slice locations.
摘要翻译： 公开了一种使用缺口RF饱和脉冲进行MR灌注采集的方法和装置。 在获取这样的MR数据时，选择要获取MR数据的片段位置量。 每个给定的切片用具有一对通带之间的阻带的缺口RF饱和脉冲来制备。 阻带被设计成不影响将要获取MR数据的下一个切片中的自旋，从而有效地增加TI并同时增加SNR和对比度。 由于缺口饱和脉冲饱和了缺口挡带外的所有旋转，所以心室内的血液被有效地饱和，使得所得到的灌注图像具有血液池抑制。 另外，90°预饱和RF脉冲的使用可以提供高度的抗心律失常作用或其他变化对患者心率的影响。 为了使阻带或陷波尽可能地保持与每个切片位置的边界重叠，优选地切片切片位置的获取。
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5.发明授权Method and apparatus for efficient stenosis identification in peripheral arterial vasculature using MR imaging 有权使用MR成像的外周动脉脉管系统有效狭窄鉴别的方法和装置公开(公告)号：US06408201B1
公开(公告)日：2002-06-18
申请号：US09591300
申请日：2000-06-09
申请人： Thomas K. F. Foo , Vincent B. Ho
发明人： Thomas K. F. Foo , Vincent B. Ho
IPC分类号： A61B505
CPC分类号： A61B5/055
摘要： A method and apparatus is disclosed to initially screen a patient's peripheral arterial vasculature for lesions, or stenotic vessels, using MR technology, and then grading the severity of any located stenosis. The invention includes tracking the passage of a contrast agent bolus through a patient, while acquiring a series of first MR images having low resolution. This initial examination uses flow sensitive bi-polar gradient waveforms with a gradient echo imaging pulse sequence to increase the sensitivity to lesion detectability. The bi-polar gradients generate a broad distribution of velocities in a large voxel. Relevant stenoses present in a voxel will result in intra-voxel flow dephasing in voxels immediate to and distal to the stenosis. After identifying a stenosis, a second MR image, having a higher resolution than the first, is used to grade the stenosis.
摘要翻译： 公开了一种方法和装置，其首先使用MR技术筛选病人的外周动脉脉管系统用于病变或狭窄血管，然后对任何位置狭窄的严重程度进行分级。 本发明包括在获取一系列具有低分辨率的第一MR图像的同时跟踪造影剂推注通过患者的通过。 该初步检查使用具有梯度回波成像脉冲序列的流敏双极梯度波形来增加对病变可检测性的敏感性。 双极梯度在大体素中产生广泛的速度分布。 存在于体素中的相关狭窄将导致体内血液流动相对于狭窄直接和远端的体素变形。 在确定狭窄后，使用比第一MR分辨率高的第二MR图像对狭窄进行分级。
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6.发明授权
公开(公告)号：US6166545A
公开(公告)日：2000-12-26
申请号：US219129
申请日：1998-12-22
IPC分类号： G01R33/561 , G01V3/00
CPC分类号： G01R33/561
摘要： A system and method is disclosed to combine both a fractional echo (k.sub.x) and a fractional NEX (k.sub.y) to reduce acquisition times and echo times in MR imaging. The method uses both zero-filling and homodyne reconstruction to construct concurrent fractional NEX and fractional echo data in a single image while minimizing any blurring effects. The system includes acquiring partial MRI data in the k.sub.x direction and acquiring partial MRI data in the k.sub.y direction. Once a partial echo and a partial NEX are acquired, the missing data is first zero-filled in the k.sub.x direction and Fourier transformed to acquire a full x direction data set. Next, the data is synthesized in the k.sub.y direction using a homodyne reconstruction technique to acquire a full data set in the k.sub.y direction. The full x,y data set can then be used to reconstruct an MR image with reduced acquisition and echo times. In order to minimize the effects of blurring in the resulting MR image, it is preferable to acquire at least an 80% fractional echo and a 60% fractional NEX. The system can be extended to any number of desirable dimensions.
摘要翻译： 公开了将分数回波（kx）和分数NEX（ky）组合以减少MR成像中的采集时间和回波时间的系统和方法。 该方法使用零填充和零差重建来构建单个图像中的并发分数NEX和分数回波数据，同时最小化任何模糊效果。 该系统包括以kx方向获取部分MRI数据并且获取ky方向上的部分MRI数据。 一旦获得了部分回波和部分NEX，则丢失的数据首先在kx方向上零填充，并进行傅里叶变换以获取全x方向数据集。 接下来，使用零差重建技术以ky方向合成数据，以获取ky方向上的完整数据集。 然后可以使用完整的x，y数据集来重建具有减少的采集和回波时间的MR图像。 为了最小化所得MR图像中模糊的影响，优选获得至少80％的分数回波和60％的分数NEX。 该系统可以扩展到任何数量的所需尺寸。
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公开(公告)号：US4783641A
公开(公告)日：1988-11-08
申请号：US84774
申请日：1987-08-13
IPC分类号： G01R33/341 , H01P7/08 , H01P7/00 , G01R33/20
CPC分类号： H01P7/082 , G01R33/341
摘要： A uniform surface current density is approximated in an RF transmitting/receiving NMR coil by employing a plurality of discrete conductors having a resonantly distributed current. Inductive and capacitive lines provide a sinusoidal current distribution with various resonant modes providing different magnetic field orientations. The distributed current reduces losses. In a second order resonant mode, decoupling of the surface coil from a transmit coil is achieved without a blocking network.
摘要翻译： 通过采用具有共振分布电流的多个离散导体，在RF发射/接收NMR线圈中近似均匀的表面电流密度。 电感和电容线提供具有提供不同磁场取向的各种谐振模式的正弦电流分布。 分布式电流降低了损耗。 在二阶谐振模式中，在没有阻塞网络的情况下实现了表面线圈与发射线圈的去耦。
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8.发明授权System and apparatus for frequency translation of magnetic resonance (MR) signals 有权用于磁共振（MR）信号频率转换的系统和装置公开(公告)号：US08686725B2
公开(公告)日：2014-04-01
申请号：US12493600
申请日：2009-06-29
申请人： Joseph Iannotti , Thomas K. F. Foo , Steven Go , Kevin Dufel
发明人： Joseph Iannotti , Thomas K. F. Foo , Steven Go , Kevin Dufel
CPC分类号： G01R33/3621 , G01R33/3685
摘要： An apparatus includes a first magnetic resonance (MR) coil element configured to output a first set of MR data at a first output frequency and a first mixer coupled to the first MR coil element. The first mixer is configured to receive the first set of MR data from the first MR coil element and frequency translate the first set of MR data to a first offset frequency different from the first output frequency by a first offset value. The apparatus also includes a digitizer coupled to the first mixer and configured to convert the frequency-translated first set of MR data into a set of digital data and a transmission line coupled to the first mixer and to the digitizer, the transmission line configured to transmit the frequency-translated first set of MR data from the MR coil element to the digitizer without a balun coupled to the transmission line.
摘要翻译： 一种装置包括第一磁共振（MR）线圈元件，其被配置为以第一输出频率输出第一组MR数据，以及耦合到第一MR线圈元件的第一混频器。 第一混频器被配置为从第一MR线圈元件接收第一组MR数据，并将第一组MR数据频率平移到与第一输出频率不同的第一偏移频率第一偏移值。 该装置还包括耦合到第一混频器的数字转换器，其被配置为将经频率转换的第一组MR数据转换成一组数字数据和耦合到第一混频器和数字转换器的传输线，该传输线被配置为传输 来自MR线圈元件的数字转换器的频率转换的第一组MR数据，而不连接到传输线的平衡 - 不平衡变换器。
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9.发明授权Efficient multi-slice acquisition with black blood contrast in fast spin echo imaging 有权在快速自旋回波成像中，采用黑色血液对比度进行高效多片段采集公开(公告)号：US07546155B2
公开(公告)日：2009-06-09
申请号：US09682685
申请日：2001-10-05
申请人： Thomas K. F. Foo , Zahi A. Fayad
发明人： Thomas K. F. Foo , Zahi A. Fayad
IPC分类号： A61B5/055
CPC分类号： A61B5/055 , A61B5/7285
摘要： The invention includes a technique for efficient multi-slice fast spin echo image acquisition with black blood contrast in cardiac imaging. The technique includes applying a non-selective inversion pulse, followed by a re-inversion pulse that is slice-selective over a region encompassing a plurality of slice selections. Execution of a series of RF excitation pulses with fast spin echo readout is timed such that signal from blood is near a null point before acquiring data for each spatial slice. For greater contrast consistency, the flip angles for the excitation pulses occurring before the null point can be reduced, and those occurring after the null point can be increased.
摘要翻译： 本发明包括在心脏成像中具有黑色血液对比度的高效多切片快速自旋回波图像采集技术。 该技术包括应用非选择性反转脉冲，随后是在包围多个切片选择的区域上切片选择的重新反转脉冲。 执行具有快速自旋回波读数的一系列RF激励脉冲的定时，使得在为每个空间切片获取数据之前，来自血液的信号接近零点。 为了获得更大的对比度一致性，可以减少在零点之前发生的激励脉冲的翻转角，并且可以增加在零点之后发生的翻转角。
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10.发明授权Method and apparatus for automated tracking of non-linear vessel movement using MR imaging 有权使用MR成像自动跟踪非线性血管运动的方法和装置公开(公告)号：US07209777B2
公开(公告)日：2007-04-24
申请号：US09728071
申请日：2000-11-30
IPC分类号： A61B5/05
CPC分类号： G01R33/56509 , A61B5/0037 , A61B5/055 , A61B5/7285 , G01R33/56 , G01R33/5673
摘要： A system and method is disclosed for tracking a moving object using magnetic resonance imaging. The technique includes acquiring a scout image scan having a number of image frames and extracting non-linear motion parameters from the number of image frames of the scout image scan. The technique includes prospectively shifting slice location using the non-linear motion parameters between slice locations while acquiring a series of MR images. The system and method are particularly useful in tracking coronary artery movement during the cardiac cycle to acquire the non-linear components of coronary artery movement during a diastolic portion of the R—R interval.
摘要翻译： 公开了一种使用磁共振成像跟踪运动物体的系统和方法。 该技术包括获取具有多个图像帧的侦察图像扫描，并从侦察图像扫描的图像帧的数量中提取非线性运动参数。 该技术包括使用切片位置之间的非线性运动参数前进移位切片位置，同时获取一系列MR图像。 该系统和方法在心脏周期期间跟踪冠状动脉运动特别有用，以在R-R间期的舒张期期间获得冠状动脉运动的非线性分量。
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