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公开(公告)号：US5938600A
公开(公告)日：1999-08-17
申请号：US767596
申请日：1996-12-09
CPC分类号： A61N7/02 , G01R33/4804 , A61B2090/374 , G01R33/563
摘要： A method of heating a target region by ultrasound radiation includes determination of a position of the target region by a magnetic resonance method. The device for carrying out this method includes an ultrasound device and an MR device. By determining movement of the target region utilizing the MR device (100) and an appropriate magnetic resonance method, and by coupling the movement information to the ultrasound device (118) by an electric signal (122, 124), it is achieved that the ultrasound device can be controlled by the movement information. Various possibilities exist for controlling the ultrasound device. According to a first possibility, the focal region is adjusted to be situated within the target region in order to generate ultrasound. Another possibility is to determine from the movement information the instant at which the target region is situated within the focal region of the ultrasound and to generate ultrasound exclusively for a brief subsequent period during which the focal region is still within the target region. Another possibility is to refrain from generating ultrasound when the movement speed is too high. Finally, the movement information can also be used for making the focal region follow the target region during the generation of ultrasound.
摘要翻译： 通过超声波辐射加热目标区域的方法包括通过磁共振法确定目标区域的位置。 用于执行该方法的装置包括超声装置和MR装置。 通过使用MR装置（100）和适当的磁共振方法来确定目标区域的移动，并且通过用电信号（122,124）将移动信息耦合到超声装置（118），实现超声波 设备可以由运动信息控制。 存在用于控制超声装置的各种可能性。 根据第一可能性，将焦点区域调整为位于目标区域内以便产生超声波。 另一种可能性是从移动信息中确定目标区域位于超声波聚焦区域内的时刻，并且专门针对焦点区域仍在目标区域内的短暂的后续周期产生超声波。 另一种可能是当移动速度太高时避免产生超声波。 最后，运动信息也可以用于在超声波产生期间使焦点区域跟随目标区域。
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公开(公告)号：US5792054A
公开(公告)日：1998-08-11
申请号：US712953
申请日：1996-09-12
IPC分类号： A61B5/055 , G01R33/48 , G01R33/563
CPC分类号： G01R33/5635 , G01R33/5605
摘要： An off-resonance magnetization transfer contrast (MTC) RF-pulse (54, 64) is used in magnetic resonance angiography (MRA) to suppress the signal of various stationary tissues, such as brain tissue while avoiding significant suppression of signal from blood flowing in a general direction of blood flow into a slice being imaged. Application of a magnetic gradient (55, 65, 85) during the MTC RF-pulse (54, 64) directed in the general direction of blood flow increases the magnetization frequency offset (86) relative to the center frequency of the MTC RF-pulse for points within and feeding blood to the slice. The MTC RF-pulse thus causes only a small signal reduction of the blood flowing into the slice in the general direction of blood flow while producing a saturation of any blood flowing into the slice in the opposite direction. Consequently, both time and RF-power needed for a separate presaturation pulse can now be used for the MTC RF-pulse.
摘要翻译： 在磁共振血管造影术（MRA）中使用非共振磁化转移对比（MTC）RF脉冲（54,64）来抑制诸如脑组织的各种静止组织的信号，同时避免对来自血液流动的信号的显着抑制 血液流入被成像的切片的大致方向。 在针对大体血流方向的MTC RF脉冲（54,64）期间施加磁梯度（55,65,85）相对于MTC RF脉冲的中心频率增加磁化频率偏移（86） 对于切片内的血液和血液进行供血。 因此，MTC RF脉冲仅导致在血流的大致方向上流入切片的血液的小信号减少，同时产生沿相反方向流入切片的任何血液的饱和度。 因此，现在可以将MTC RF脉冲用于单独的预饱和脉冲所需的时间和RF功率。
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公开(公告)号：US5800354A
公开(公告)日：1998-09-01
申请号：US345026
申请日：1994-11-23
IPC分类号： G01R33/28 , A61B5/055 , G01R33/565 , G01R33/567
CPC分类号： G01R33/56563 , G01R33/5676
摘要： In a magnetic resonance method for imaging of a moving part of a body (106) temporary magnetic gradient fields (230) are applied and a echo signal (641, 642) is obtained after an excitation pulse (201). An image of the moving part is reconstructed from the received echo signals (240). The moving part introduces artefacts in the reconstructed image. These artefacts could be reduced when the instantaneous position of the moving part is known and the region of the moving part to be excited is adjusted according to this instantaneous position. This instantaneous position is derived from navigator signals (640). These navigator signals (640) could be generated independently from the other echo signals (641, 642) in the moving part of the body. A further reduction of artefacts in the image could be obtained by deriving a phase correction and a frequency correction from the navigator signals (640) and to apply the derived corrections to the received echo signals (641, 642). Also this method could be combined with ECG-triggering and respiratory gating.
摘要翻译： 在用于对身体的运动部分（106）成像的磁共振方法中，施加临时磁梯度场（230），并且在激励脉冲（201）之后获得回波信号（641,642）。 从接收到的回波信号（240）重建运动部分的图像。 移动部分在重建图像中引入人为因素。 当已知活动部件的瞬时位置并且根据该瞬时位置调整要被激励的活动部件的区域时，可以减少这些人造物。 该瞬时位置是从导航信号（640）导出的。 这些导航信号（640）可以独立于身体的运动部分中的其他回波信号（641,642）生成。 通过从导航器信号（640）导出相位校正和频率校正，并且将导出的校正应用于接收到的回波信号（641,642），可以获得图像中的伪像的进一步减少。 此外，该方法可以与ECG触发和呼吸门控组合。
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