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公开(公告)号：EP1307757A1
公开(公告)日：2003-05-07
申请号：EP01960497.4
申请日：2001-07-13
发明人： FUDERER, Miha , VAN DEN BRINK, Johan, S. , JURRISSEN, Michel, P., J. , VAN MUISWINKEL, Arianne, M., C. , KATSCHER, Ulrich
IPC分类号： G01R33/561 , G01R33/3415
CPC分类号： G01R33/5611 , G01R33/4835
摘要： A magnetic resonance imaging method employs sub-sampled signal acquisition from a number of receiver coils such as surface coils. A full field-of-view magnetic resonance image is reconstructed on the basis of the sensitivity profiles of the receiver coils, for example on the basis of the SENSE technique. The reconstruction is carried out mathematically as an optimization, for example, requiring a minimum noise level in the magnetic resonance image. According to the invention, a priori information is also involved in the reconstruction and the a priori information is taken into account especially as a constraint in said optimization.
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公开(公告)号：EP1779129A1
公开(公告)日：2007-05-02
申请号：EP05772339.7
申请日：2005-07-21
IPC分类号： G01R33/3415
CPC分类号： G01R33/3415
摘要： The magnetic resonance apparatus comprises a carrier (8) to position an object (7), notably a patient to be imaged in an imaging volume V, first magnet system (2), a second magnet system (3), a power supply unit (4), an RF transmitter and modulator (6), an RF transmitter coil (5), a plurality of receiver elements (18, 19), a transmitter-receiver circuit (9), a signal amplifier and demodulation unit (10), a processing unit (12), an image processing unit (13), a monitor (14), and a control unit (11). The gradient coils (3) are fed by the power supply unit (4). The RF transmitter coil (5) serves to generate RF magnetic fields and is connected to the RF transmitter and modulator (6). The transmitter coil (5) is connected to the signal amplifier and demodulator unit (10) via the transmitter-receiver circuit (9). Receiver elements (18, 19), positioned at their respective locations L1, L2 on the carrier (8), are arranged to detect a response of the object to the RF magnetic fields. The control unit (11) controls the RF transmitter and modulator (6), the power supply unit (4) and automatically selects suitable receiver elements (18, 19) to detect the response of the object (7) to the magnetic resonance excitation.
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公开(公告)号：EP1659972A1
公开(公告)日：2006-05-31
申请号：EP04744265.2
申请日：2004-08-09
CPC分类号： A61B5/0046 , A61B50/10 , A61B50/20 , A61B50/33 , A61B90/90 , A61B2017/00017 , A61B2090/0805 , A61B2090/0806
摘要： A subject on a pallet (22) undergoes a surgical procedure in the vicinity of an MR scanner using non-MRI compatible instruments (40) from a tray (42). The procedure may, for example, insert a catheter which is MRI compatible. After the procedure, the pallet (22) is transferred by a transfer gurney (26') or a drive (122) and moved across a 5 Gauss line (32) and into an imaging region (30) of an MRI scanner (12). To be sure that none of the non-MRI compatible instruments crosses the 5 Gauss line (32), a circuit (50) senses whether all of the instruments have been repositioned at their preselected locations in the tray (42). The circuit (50) controls one of a light (60) which indicates whether or not it is safe to cross the 5 Gauss line, prevents brakes on the movable transport gantry (26) from being released, prevents a pallet manipulating mechanism (24) from transferring the pallet to the transport gantry, or prevents the transport gantry from being released from its docking position with the manipulating mechanism (24).
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公开(公告)号：EP1047953B1
公开(公告)日：2006-03-22
申请号：EP99958016.0
申请日：1999-11-09
IPC分类号： G01R33/563
CPC分类号： G01R33/56308 , G01R33/5673
摘要： The invention relates to a method for in vivo measurement of a periodically varying fluid flow in an object by means of magnetic resonance. The method includes a step for applying first and second additional magnetic field gradients in order to shift the phase of a reference magnetization, which phase shift relates to a net flow of the fluid during an interval between the application of the additional magnetic field gradients. According to the invention, near a phase of a period of the periodically varying fluid flow an excitation RF pulse is generated, the first additional gradient is applied and a first additional RF pulse is generated and near a corresponding phase of a second period of the periodically varying fluid flow a second additional RF pulse is generated and the second additional gradient is applied.
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公开(公告)号：EP1611452A1
公开(公告)日：2006-01-04
申请号：EP04722617.0
申请日：2004-03-23
IPC分类号： G01R33/563
CPC分类号： G01R33/56341
摘要： The present invention relates to a method of perfusion imaging comprising: performing a first magnetic resonance data acquisition (A) at a first sensitivity (b) value, performing a set of at least six second magnetic resonance data acquisitions (B1, B2,… B6) with gradiant encodings in different directions at second sensitivity (b) values, determining a perfusion tensor based on the magnetic resonance data acquisitions, performing a perfusion tensor visualitation step.
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公开(公告)号：EP1567881A1
公开(公告)日：2005-08-31
申请号：EP03811834.5
申请日：2003-11-20
IPC分类号： G01R33/561 , G01R33/3415
CPC分类号： G01R33/5611
摘要： A novel magnetic resonance imaging method is presented for forming an image of an object from a plurality of signals acquired by an array of multiple receiver antennae. Prior to imaging a sensitivity map of each of the receiver antennae is provided, at least two adjacent antennae record signals originating from the same imaging position and the image intensity is calculated from the signals measured by different antennae, wherein the number of phase encoding steps is reduced with respect to the full set thereof. In addition the field of view is set smaller than the object size in phase encoding direction inducing intrinsic foldover artefacts, whereas the sensitivity map of the receiver antennae and a reference image featuring intrinsic foldover artefacts are used for reconstruction of the MR image to an unfolded image.
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公开(公告)号：EP1182970A2
公开(公告)日：2002-03-06
申请号：EP00990690.0
申请日：2000-12-07
IPC分类号： A61B8/00
CPC分类号： G01R33/4814 , A61B8/00 , A61B8/5238 , Y10S128/922
摘要： A diagnostic imaging system, notably a magnetic resonance imaging system comprises a receiver antenna for picking-up magnetic resonance signals and an ultrasound probe for receiving ultrasound echoes. A reconstruction unit is arranged to reconstruct a diagnostic image from the magnetic resonance signals and the ultrasound echoes. In particular, the magnetic resonance image and ultrasound images are registered in a common reference frame and geometric distortions in the ultrasound image are corrected on the basis of the magnetic resonance image. Different tissue types are distinguished in the magnetic resonance image and corrections are made for differences between ultrasound sound velocities in these tissue types. Further, information contained in the magnetic resonance signals can be displayed in combination in the ultrasound echoes.
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公开(公告)号：EP1425598B1
公开(公告)日：2010-03-24
申请号：EP02760449.5
申请日：2002-08-12
IPC分类号： G01R33/48
CPC分类号： G01R33/446 , G01R33/3415 , G01R33/4616 , G01R33/5611
摘要： A magnetic resonance imaging system comprises an excitation antennae system (13,16) including several antennae for emitting an RF-excitation field [Bl(t)]. An activation control unit (ACU) is coupled to the excitation antennae system to activate the excitation antennae system.Individual antennae are activated to simultaneously emit separate RF-excitation constituents [Bn(t)]. The RF-excitation constituents have different activation distributions over k-space. and the time required for the RF-excitation is short even for complex spatial excitation patterns.
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公开(公告)号：EP1549966B1
公开(公告)日：2009-11-18
申请号：EP03798988.6
申请日：2003-09-12
IPC分类号： G01R33/561
CPC分类号： G01R33/5615 , G01R33/4835 , G01R33/561
摘要： The invention relates to a method for interleaved k-space data acquisition for magnetic resonance imaging (MRI), the k-spaces having a first coordinate axis and a second coordinate axis, the method comprising: a) sampling into a first direction along the first coordinate axis, b) applying a first compensation pulse, c) sampling into a second direction along the first coordinate axis, the second direction being opposite to the first direction, applying a second compensation pulse, d) repetitively carrying out the steps a) to d).
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公开(公告)号：EP1687650A1
公开(公告)日：2006-08-09
申请号：EP04770147.9
申请日：2004-10-01
IPC分类号： G01R33/28 , G01R33/561
摘要： The invention relates to a system and method for magnetic resonance imaging. In order to achieve high resolution imaging a magnetic resonance imaging system and method is proposed, wherein magnetic resonance signals using a first resonance frequency are used for a central portion of k-space and magnetic resonance signals using a second resonance frequency are used for a peripheral portion of k-space. In a preferred embodiment of the invention non-proton magnetic resonance signals are used for the central portion of the k-space and proton magnetic resonance signals are used for the periphery of k-space. Accordingly, the reconstructed magnetic resonance image shows contrast relating to the non-proton nuclei and fine resolution dominated by the protons. Hence, the invention can especially provide a solution for the limited time available for the acquisition of non-proton magnetic resonance signals.
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