利索-全球专利检索

  1. 登录
  2. 注册

搜索结果

5 条记录 (耗时 0.008 秒)

    Steady state free precession magnetic resonance imaging using phase detection for material separation
    1.
    发明申请
    Steady state free precession magnetic resonance imaging using phase detection for material separation 有权
    稳态自由进动磁共振成像使用相位检测进行材料分离

    公开(公告)号：US20050040821A1

    公开(公告)日：2005-02-24

    申请号：US10643286

    申请日：2003-08-18

    申请人： Brian Hargreaves ,  Shreyas Vasanawala

    发明人： Brian Hargreaves ,  Shreyas Vasanawala

    IPC分类号： G01R33/54 ,  G01R33/561 ,  G01V3/00

    CPC分类号： G01R33/4828 ,  G01R33/5613

    摘要： Magnetic resonance imaging of a body uses steady state free precession with material separation for the selective imaging of two species, such as blood or fat. The refocusing property of SSFP is used with signal phase detection to suppress either water or lipid. Phase and/or frequency of the RF excitation pulse and repetition time are selected so that resonant frequencies of water, fw, and lipid, fl, are on opposite sides of the signal null frequency.

    摘要翻译： 身体的磁共振成像使用稳态自由进动，物质分离用于两种物质如血液或脂肪的选择性成像。 SSFP的重新聚焦特性用于信号相位检测以抑制水或脂质。 选择RF激励脉冲和重复时间的相位和/或频率，使得水，fw和脂质f1的共振频率在信号零频率的相对侧。

    Steady state free precession magnetic resonance imaging using phase detection of material separation
    4.
    发明授权
    Steady state free precession magnetic resonance imaging using phase detection of material separation 有权
    稳态自由进动磁共振成像使用相位检测材料分离

    公开(公告)号：US06922054B2

    公开(公告)日：2005-07-26

    申请号：US10643286

    申请日：2003-08-18

    申请人： Brian A. Hargreaves ,  Shreyas Vasanawala

    发明人： Brian A. Hargreaves ,  Shreyas Vasanawala

    IPC分类号： G01R33/54 ,  G01R33/561 ,  G01V3/00

    CPC分类号： G01R33/4828 ,  G01R33/5613

    摘要： Magnetic resonance imaging of a body uses steady state free precession with material separation for the selective imaging of two species, such as blood or fat. The refocusing property of SSFP is used with signal phase detection to suppress either water or lipid. Phase and/or frequency of the RF excitation pulse and repetition time are selected so that resonant frequencies of water, fw, and lipid, fl, are on opposite sides of the signal null frequency.

    摘要翻译： 身体的磁共振成像使用稳态自由进动，物质分离用于两种物质如血液或脂肪的选择性成像。 SSFP的重新聚焦特性用于信号相位检测以抑制水或脂质。 选择RF激励脉冲和重复时间的相位和/或频率，使得水，fw和脂质f1的共振频率在信号零频率的相对侧。

    Catalyzing the transient response in steady-state MRI sequences
    5.
    发明授权
    Catalyzing the transient response in steady-state MRI sequences 有权
    在稳态MRI序列中催化瞬时反应

    公开(公告)号：US06452387B1

    公开(公告)日：2002-09-17

    申请号：US09801424

    申请日：2001-03-07

    申请人： Brain A. Hargreaves ,  Shreyas Vasanawala ,  John M. Pauly ,  Dwight G. Nishimura

    发明人： Brain A. Hargreaves ,  Shreyas Vasanawala ,  John M. Pauly ,  Dwight G. Nishimura

    IPC分类号： G01V300

    CPC分类号： G01R33/5613

    摘要： A steady-state condition for tipped nuclear spins is accelerated or catalyzed by first determining magnetization magnitude of the steady state and the scaling magnetization along one axis (Mz) to at least approximate the determined magnetization magnitude. Then the scaled magnetization is rotated to coincide with a real-valued eigenvector extension of the tipped steady-state magnetization. Any error vector will then decay to the steady-state condition without oscillation. In one embodiment, the magnetic resonance imaging utilizes steady-state free precession (SSFP). The scaling and rotating steps are followed by the steps of applying read-out magnetic gradients and detecting magnetic resonance signals from the tipped nuclear spins. The magnetization magnitude is determined by eigenvector analysis, and the eigenvector extension is a real-valued eigenvector determined in the analysis.

    摘要翻译： 通过首先确定稳态的磁化强度和沿着一个轴（Mz）的缩放磁化强度至少接近确定的磁化强度，来加速或催化尖端核自旋的稳态条件。 然后，缩放的磁化被旋转以与尖端稳态磁化的实数特征向量延伸一致。 任何误差矢量都会衰减到稳态，而不会产生振荡。 在一个实施例中，磁共振成像利用稳态自由进动（SSFP）。 缩放和旋转步骤之后是应用读出磁梯度并从尖端核自旋检测磁共振信号的步骤。 磁化强度由特征向量分析确定，特征向量扩展是在分析中确定的实值特征向量。