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公开(公告)号：US10088543B2
公开(公告)日：2018-10-02
申请号：US14774314
申请日：2014-03-11
发明人： Peter Bornert , Mariya Ivanova Doneva , Kay Nehrke
IPC分类号： G01V3/00 , G01R33/561 , G01R33/36 , G01R33/385 , G01R33/483
摘要： The invention relates to a method of MR imaging of an object (10) placed in an examination volume of a MR device (1). The method comprises the steps of: —subjecting the object (10) to an imaging sequence comprising phase-modulated multi-slice RF pulses for simultaneously exciting two or more spatially separate image slices, —acquiring MR signals, wherein the MR signals are received in parallel via a set of at least two RF coils (11, 12, 13) having different spatial sensitivity profiles within the examination volume, and —reconstructing a MR image for each image slice from the acquired MR signals, wherein MR signal contributions from the different image slices are separated on the basis of the spatial sensitivity profiles of the at least two RF coils (11, 12, 13) and on the basis of the phase modulation scheme of the RF pulses. In order to optimize the conditioning of the inverse problem of the MR image reconstruction, the phase-modulation scheme of the RF pulses is derived from the spatial sensitivity profiles of the at least two RF coils (11, 12, 13). Moreover, the invention relates to a MR device for carrying out this method as well as to a computer program to be run on a MR device.
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公开(公告)号：US10222437B2
公开(公告)日：2019-03-05
申请号：US15030430
申请日：2014-10-14
发明人： Kay Nehrke , Peter Bornert
IPC分类号： G01R33/48 , A61B5/055 , G01R33/561
摘要： The invention relates to a method of MR imaging of an object (10) placed in the examination volume of a MR device (1). It is the object of the invention to provide an improved MR-based temperature mapping method. The method of the invention comprises the steps of: subjecting the object (10) to an imaging sequence of RF pulses and switched magnetic field gradients, which imaging sequence is a stimulated echo sequence including: a) at least two preparation RF pulses (a) radiated toward the object (10) during a preparation period (21), and b) one or more reading RF pulses (β) radiated toward the object (10) during an acquisition period (22) temporally subsequent to the preparation period (21); acquiring at least two MR signals during the acquisition period (22), wherein the two MR signals are either (i) a FID signal (I1, FID) and a stimulated echo signal (I2) or (ii) two stimulated echo signals (STE, STE*); and deriving a temperature map indicating the spatial distribution of the temperature within the object (10) from the at least two acquired MR signals. Moreover, the invention relates to a MR device (1) and to a computer program for a MR device (1).
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公开(公告)号：US20230122915A1
公开(公告)日：2023-04-20
申请号：US17914435
申请日：2021-03-24
发明人： Kay Nehrke , Peter Boernert
IPC分类号： G01R33/565 , G01R33/48 , G01R33/56 , G06N3/08
摘要： Abstract: Disclosed herein is a medical system comprising a memory (110) storing machine executable instructions (120) and a trained neural network (122). The trained neural network is configured to output corrected magnetic resonance image data (130) in response to receiving as input a set of magnetic resonance images (126) each having a different spatially constant frequency off-resonance factor. The medical system further comprises a computational system (106) configured for controlling the medical system, wherein execution of the machine executable instructions causes the computational system to: receive (200) k-space data (124) acquired according to a magnetic resonance imaging protocol; reconstruct (202) a set of magnetic resonance images (126) according to the magnetic resonance imaging protocol, wherein each of the set of magnetic resonance images is reconstructed assuming a different spatially constant frequency off-resonance factor chosen from a list of frequency off-resonance factors (128); and receive (204) the corrected magnetic resonance image data in response to inputting the set of magnetic resonance images into the trained neural network.
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公开(公告)号：US10830856B2
公开(公告)日：2020-11-10
申请号：US16340492
申请日：2017-09-28
发明人： Peter Boernert , Miha Fuderer , Kay Nehrke , Klaas Pruessmann , Jurgen Edwin Rahmer , Bertram Wilm , Christian Stehning
IPC分类号： G01V3/00 , G01R33/565 , G01R33/385 , G01R33/561 , G01R33/24
摘要： A magnetic resonance imaging system includes a gradient system and a processor for controlling the magnetic resonance imaging system. Execution of machine executable instructions causes the magnetic resonance imaging system to: acquire by coil elements first magnetic resonance data simultaneously from a group of passive local probes, wherein the first group of passive local probes includes a plurality of passive local probes located spaced apart from each other; disentangle contributions to the first magnetic resonance data from the individual local probes, calculate for the magnetic resonance imaging system a gradient impulse response function of the gradient system using the first magnetic resonance data from the local probes; and determine correction factors using the gradient impulse response function
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公开(公告)号：US10018690B2
公开(公告)日：2018-07-10
申请号：US14652836
申请日：2013-12-11
CPC分类号： G01R33/243 , G01R33/34 , G01R33/385 , G01R33/58
摘要： The present invention provides a phantom (200) for use in a magnetic resonance (MR) imaging system (110) with a set of resonating volumes (206) positioned in a base body (202), whereby the base body (202) has a spherical or ellipsoid shape in accordance with a volume of interest (203) of the MR imaging system (110), and the resonating volumes (206) are located at a circumference of the base body (202). The phantom is used in a method for evaluating the magnetic field of a main magnet (114) of a magnetic resonance (MR) imaging system (110), comprising the steps of positioning the phantom (200) within the main magnet (114), performing a 3D spectroscopic MR measurement of the phantom (200) using the MR imaging system (110), thereby measuring resonances of the resonating volumes (206), assigning the measured resonances to the resonating volumes (206), and evaluating the magnetic field of the main magnet (114) from the MR measurement of the phantom (200) based on the measured resonances of the resonating volumes (206). Accordingly, the MR imaging system itself is directly used for determining the magnetic field of its main magnet. Accordingly, the MR imaging system itself can be used as measurement equipment, instead of a separate NMR magnetometer, which is required for conventional determination of the magnetic field.
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公开(公告)号：US09977108B2
公开(公告)日：2018-05-22
申请号：US14432931
申请日：2013-09-11
IPC分类号： G01R33/20 , G01R33/561 , G01R33/24 , A61B5/055 , G01R33/34 , G01R33/36 , G01R33/385
CPC分类号： G01R33/5611 , A61B5/055 , G01R33/246 , G01R33/34 , G01R33/36 , G01R33/385
摘要： The invention relates to a method of parallel MR imaging, wherein a reference scan is performed by means of a stimulated echo sequence including i) at least two preparation RF pulses (α) radiated toward a portion of a body (10) during a preparation period (21), and ii) one or more reading RF pulses (β) radiated toward the portion of the body (10) during an acquisition period (22) temporally subsequent to the preparation period (21). One or more FID signals (I1) and one or more stimulated echo signals (I2) are acquired during the acquisition period (22). The spatial receive and/or—if applicable—transmit4 sensitivity profiles of at least two RF coils (11, 12, 13) are derived from the acquired FID signals (I1) and/or from the acquired stimulated echo signals (I2). The parameters of the stimulated echo sequence are selected such that it is robust against susceptibility-induced artifacts. Moreover, 10 the invention relates to a MR device (1) and to a computer program for a MR device (1).
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公开(公告)号：US10816625B2
公开(公告)日：2020-10-27
申请号：US16095954
申请日：2017-04-26
发明人： Peter Bornert , Kay Nehrke , Mariya Ivanova Doneva , Thomas Erik Amthor , Peter Koken , George Randall Duensing
IPC分类号： G01R33/50 , G01R33/48 , G01R33/56 , G01R33/561 , G01R33/563 , G01R33/485
摘要： The invention provides for a magnetic resonance imaging system (100) for acquiring magnetic resonance data (142) from a subject (118) within an imaging zone (108). The magnetic resonance imaging system comprises a memory (134, 136) for storing machine executable instructions (160), and pulse sequence commands (140, 400, 502, 600, 700), wherein the pulse sequence commands are configured to cause the magnetic imaging resonance system to acquire the magnetic resonance data according to a magnetic resonance fingerprinting technique. The pulse sequence commands are further configured to control the magnetic resonance imaging system to perform spatial encoding using a zero echo time magnetic resonance imaging protocol. Execution of the machine executable instructions causes the processor controlling the MRI system to: acquire (200) the magnetic resonance data by controlling the magnetic resonance imaging system with the pulse sequence commands; and calculate (202) a spatial distribution (146) of each of a set of predetermined substances by comparing the magnetic resonance data with a magnetic resonance fingerprinting dictionary (144).
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公开(公告)号：US10591565B2
公开(公告)日：2020-03-17
申请号：US15572182
申请日：2016-04-28
发明人： Kay Nehrke , Peter Boernert
IPC分类号： G01R33/561 , G01R33/24 , G01R33/56
摘要： The invention relates to a method of MR imaging of an object (10). The problem of the invention is to provide an improved MR imaging technique that enables fast and robust determination of spatial sensitivity profiles of RF receiving antennas (11, 12, 13) used in parallel imaging as well as B1 and/or B0 mapping. The method of the invention comprises subjecting the object (10) to a stimulated echo sequence. Two or more stimulated echo signals (STE, STE*) are acquired, namely a direct stimulated echo signal (STE) and a conjugated stimulated echo signal (STE*), wherein at least one of the stimulated echo signals (STE, STE*) is received in parallel via an array of two or more RF receiving antennas (11, 12, 13) having different spatial sensitivity profiles, and wherein at least another one of the stimulated echo signals (STE, STE*) is received via a body RF coil (9) having an essentially homogeneous spatial sensitivity profile. Sensitivity maps indicating the spatial sensitivity profiles of the individual RF receiving antennas (11, 12, 13) of the array are derived by comparing the stimulated echo signals (STE, STE*) received via the array of RF receiving antennas (11, 12, 13) with the stimulated echo signals (STE, STE*) received via the body RF coil (9). Moreover, the invention relates to a MR device (1) and to a computer program for a MR device (1).
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公开(公告)号：US10591562B2
公开(公告)日：2020-03-17
申请号：US15735314
申请日：2016-06-07
发明人： Peter Boernert , Kay Nehrke , Holger Eggers
摘要： The invention provides for a medical instrument (100, 500) comprising a magnetic resonance imaging system (102) for acquiring magnetic resonance data (142) from a subject (118) within an imaging zone (108). The magnetic resonance imaging system comprises: a main magnet (104) for generating a B0 magnetic field within the imaging zone; a memory (134, 136) containing machine executable instructions (160, 162, 164, 166) and pulse sequence commands (140); a processor (130) for controlling the medical instrument. Execution of the machine executable instructions causes the processor to: acquire (200) the magnetic resonance data by controlling the magnetic resonance imaging system with the pulse sequence commands; receive (202) a subject magnetic susceptibility map (144) of the subject; calculate (204) a B0 inhomogeneity map (146) from the magnetic resonance data; calculate (206) a subject B0 magnetic field perturbation (148) from the subject magnetic susceptibility map; calculate (208) a residual B0 magnetic field perturbation (150) by subtracting the subject B0 magnetic field perturbation from the B0 inhomogeneity map; and calculate (210) a bone map (152) from the residual B0 magnetic field perturbation.
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公开(公告)号：US20150253406A1
公开(公告)日：2015-09-10
申请号：US14432931
申请日：2013-09-11
IPC分类号： G01R33/561 , A61B5/055 , G01R33/34 , G01R33/36 , G01R33/385
CPC分类号： G01R33/5611 , A61B5/055 , G01R33/246 , G01R33/34 , G01R33/36 , G01R33/385
摘要： The invention relates to a method of parallel MR imaging, wherein a reference scan is performed by means of a stimulated echo sequence including i) at least two preparation RF pulses (a) radiated toward a portion of a body (10) during a preparation period (21), and ii) one or more reading RF pulses 03) radiated toward the portion of the body (10) during an acquisition period (22) temporally subsequent to the preparation period (21). One or more FID signals (I1) and one or more stimulated echo signals (I2) are acquired during the acquisition period (22). The spatial receive and/or—if applicable—transmit4 sensitivity profiles of at least two RF coils (11, 12, 13) are derived from the acquired FID signals (I1) and/or from the acquired stimulated echo signals (I2). The parameters of the stimulated echo sequence are selected such that it is robust against susceptibility-induced artefacts. Moreover, 10 the invention relates to a MR device (1) and to a computer program for a MR device (1).
摘要翻译： 本发明涉及一种并行MR成像的方法，其中通过受激回波序列执行参考扫描，所述回波序列包括i）在准备期间向身体（10）的一部分辐射的至少两个准备RF脉冲（a） （21），以及ii）在所述准备期间（21）之后的采集周期（22）期间朝向所述身体（10）的所述部分辐射的一个或多个读取RF脉冲03）。 在采集周期（22）期间获取一个或多个FID信号（I1）和一个或多个受激回波信号（I2）。 至少两个RF线圈（11,12,13）的空间接收和/或 - 如果可应用的传输4灵敏度分布是从所获取的FID信号（I1）和/或从获取的受激回波信号（I2）导出的。 选择刺激回波序列的参数，使其对抗敏感性诱导的伪像是鲁棒的。 此外，本发明涉及MR装置（1）和用于MR装置（1）的计算机程序。
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