5 results about "Repetition Time" patented technology

Embodiments of the present application disclose a multi-echo data magnetic resonance imaging scanning method, device and magnetic resonance imaging system. The method comprises: in the process of multi-echo data magnetic resonance imaging scanning on an imaging target, if automatic calibration data needs to be collected in the current repetition time, and the position of the automatic calibration data in K space is inconsistent with the position of any imaging data in K space which needs to be collected in the current repetition time, then: when the plateau signal of the first readout gradient in the readout direction is applied, start to apply an offset gradient in the phase encoding direction, wherein the first readout gradient is any readout gradient in the readout direction except the last readout gradient; and during the application of the plateau signal of the dephasing gradient of the first readout gradient in the readout direction, the automatic calibration data is collected. Embodiments of the present application avoid TR oscillation in multi-echo data MR imaging scanning, and realize the continuity of the collected automatic calibration data and imaging data.

The application relates to a magnetic resonance signal acquisition method and device, computer equipment and a storage medium. The method comprises the following steps: acquiring the number of groups of multi-layer simultaneous excitation of radio frequency pulses for a target object; when the number of groups of multi-layer simultaneous excitation is even, adjusting a preset excitation timing for a target layer group to obtain a target excitation timing; the target layer group comprises a group of layers that are first or last excited in a repetition time of the radio frequency pulses; in the target excitation timing, spatially adjacent layers are not adjacent in the timing; controlling the radio frequency pulses based on the target excitation timing to perform multi-layer simultaneous excitation processing on the target object; acquiring multi-layer simultaneous excitation data of the target object; and the multi-layer simultaneous excitation data is used for magnetic resonance imaging of the target object. The method can improve the magnetic resonance imaging effect.

The invention relates to a method of MR imaging of at least a portion of a body (10) of a patient placed in an examination volume of an MR system (1). It is an object of the invention to provide an improved fast gradient echo imaging technique with the ability to obtain angiographic information. The method of the invention comprises the steps of subjecting the body portion to a magnetization preparation RF pulse (MP); subjecting the body portion to a gradient echo imaging sequence comprising a series of RF excitations (EP) after a preparation delay (TD), wherein a phase encoding gradient (PE) and a refocusing gradient (RO) and at least one bipolar velocity encoding gradient (VE) pair are applied in repetition time intervals (TR) between successive RF excitations (EP) to sample a predefined region of k-space and generate gradient echoes in each repetition time interval (TR); acquiring echo signals from the body portion; reconstructing a morphological MR image of the body portion from the acquired echo signals; and deriving phase contrast angiographic information from the phase imparted on the echo signals by the velocity encoding gradients (VE). Furthermore, the invention also relates to an MR system (1) and a computer program.

The disclosed systems and methods use the developed Flexible Relaxation and Saturation Time (FIRST) approach to provide customization of parameters for a Magnetization Transfer (MT) sequences to maximize sensitivity and efficiency. The methods may include generating one or more customized parameters for one or more iterations of a Magnetization Transfer Magnetic Resonance (MR) sequence that is executed on a Magnetic Resonance Imaging (MRI) System. The generating may include receiving input parameters for each iteration of the sequence. The one or more input parameters may include radiofrequency (RF) offset and / or saturation power. The generating may further include determining a set of one or more customized parameters for each iteration using the input parameters for each RF offset and / or saturation power. The one or more customized parameters may include repetition time (TR).