Method and apparatus for MR perfusion image acquisition using a notched RF saturation pulse
    1.
    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。

    Rapid multi-slice MR perfusion imaging with large dynamic range
    2.
    发明授权
    Rapid multi-slice MR perfusion imaging with large dynamic range 有权
    快速多片MR灌注成像具有较大的动态范围

    公开(公告)号:US07283862B1

    公开(公告)日:2007-10-16

    申请号:US10063832

    申请日:2002-05-16

    IPC分类号: A61B5/05

    摘要: The present invention includes a method and apparatus to perform rapid multi-slice MR imaging without ECG gating or requiring breath-holding that is capable of renal profusion analysis and angiographic screening. An ungated interleaved pulse sequence is applied in rapid succession, followed by a delay interval. The ungated interleaved pulse sequence is repeatedly played out with the predefined delay interval between each application of the pulse sequence. The resulting images provide not only a series of temporal phases of contrast-enhanced blood uptake for renal profusion analysis, but also provide enough dynamic range to include angiographic screening of the renal arteries.

    摘要翻译: 本发明包括一种方法和装置,用于执行无需ECG门控的快速多切片MR成像或需要能够进行肾分泌分析和血管造影筛选的呼吸保持。 以快速连续的方式施加非啮合交错脉冲序列,然后是延迟间隔。 在脉冲序列的每个应用之间以预定的延迟间隔重复播放非同步交织的脉冲序列。 所得到的图像不仅提供用于肾分泌分析的对比度增强的血液摄取的一系列时间阶段,而且还提供足够的动态范围以包括肾动脉的血管造影筛查。

    Method and system for MRI venography including arterial and venous discrimination
    3.
    发明授权
    Method and system for MRI venography including arterial and venous discrimination 失效
    MRI静脉造影的方法和系统,包括动脉和静脉鉴别

    公开(公告)号:US06192264B1

    公开(公告)日:2001-02-20

    申请号:US09221500

    申请日:1998-12-28

    IPC分类号: A61B5055

    CPC分类号: A61B5/055 A61B5/0037

    摘要: A system and method for arterial and venous discrimination in MR venography is disclosed. By setting a noise level in the phase image (that is proportional to the velocity encoding value) at a threshold level between that of the arterial signals and the venous signals during the diastole portion of the cardiac cycle and acquiring a phase contrast MR image during the diastole portion, the arterial signals are effectively suppressed and a venous only image can be reconstructed. Post-processing steps are disclosed which can alternatively provide an arterial only image. By separately reconstructing a magnitude image and a phase image map to produce a magnitude image and a phase image, a masking module can create an output displaying venous only or arterial only images based on a user selection. The present invention allows for a complete noninvasive angiography exam to be completed within approximately 30 minutes.

    摘要翻译: 公开了MR静脉造影中的动脉和静脉鉴别的系统和方法。 通过在心动周期的舒张期期间将相位图像中的噪声电平(与速度编码值成比例)设置在动脉信号与静脉信号之间的阈值水平,并在心脏周期的舒张期期间获取相位对比MR图像 舒张部分,有效地抑制动脉信号,并且可以重建仅静脉图像。 公开了后处理步骤,其可以替代地提供仅动脉图像。 通过分别重建幅度图像和相位图像映射以产生幅度图像和相位图像,掩蔽模块可以基于用户选择创建仅显示静脉或仅主动图像的输出。 本发明允许在大约30分钟内完成完整的非侵入性血管造影检查。

    System and method for determining a cardiac axis
    4.
    发明授权
    System and method for determining a cardiac axis 有权
    用于确定心轴的系统和方法

    公开(公告)号:US08165377B2

    公开(公告)日:2012-04-24

    申请号:US12323594

    申请日:2008-11-26

    IPC分类号: G06K9/00 A61B5/05

    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。

    Method and apparatus for efficient stenosis identification in peripheral arterial vasculature using MR imaging
    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

    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。

    Real-time MR image subtraction and reconstruction
    6.
    发明授权
    Real-time MR image subtraction and reconstruction 失效
    实时MR图像减法与重建

    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

    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。

    MRI reconstruction using partial echo and partial NEX data acquisitions
    7.
    发明授权
    MRI reconstruction using partial echo and partial NEX data acquisitions 失效
    使用部分回波和部分NEX数据采集进行MRI重建

    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。

    System and apparatus for frequency translation of magnetic resonance (MR) signals
    9.
    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

    IPC分类号: G01V3/00 G01R33/20

    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。

    Efficient multi-slice acquisition with black blood contrast in fast spin echo imaging
    10.
    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

    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。