5 results about "Fat saturation" patented technology

The invention relates to a computer-implemented method for acquiring magnetic resonance data with a magnetic resonance device (18), wherein a magnetic resonance sequence is used in which, during an equilibrium state in a sequence segment maintained by regular excitation modules (9, 9a - 9e) with at least one excitation pulse, both a first readout time window (11, 11a - 11e) immediately following an excitation module (9, 9a - 9e) for measuring magnetic resonance data of a free induction decay and second readout time windows (12, 12a - 12e), which are spaced at least the first readout duration of the first readout time window (11, 11a - 11e) from a last excitation module (9, 9a - 9e), which acts as a refocusing module for the penultimate excitation module (9, 9a - 9e), are used for measuring magnetic resonance data of a spin echo. become,wherein, between at least one pair consisting of a starting excitation module (9c) and a final excitation module (9d) that follow one another, a fat saturation module (15) with at least one high-frequency fat saturation pulse (16) is output in the magnetic resonance sequence during a preparation period (14).

Disclosed in the present invention are a 3D navigator-based 3D gradient spin-echo diffusion imaging method, and a device. The method comprises: first, using a global saturation module to destroy previous residual transverse magnetization; second, by means of a diffusion encoding module, embedding a pair of trapezoidal cosine oscillation gradients or pulse gradients into radio frequency pulses of 90°x-180°y-90°-x, and separating diffusion encoding from signal acquisition; then using a fat saturation module to suppress a fat signal; using a 3D gradient spin-echo readout method to acquire an image signal; and finally, acquiring a 3D navigation echo signal in the last spin echo for correcting a phase error between multiple excitations. The present invention can effectively eliminate phase errors between multiple acquisitions and realize high-resolution whole-brain diffusion imaging. Compared with 2D echo planar imaging, the present invention increases the signal-to-noise ratio of diffusion magnetic resonance imaging, thereby supporting higher-resolution whole-brain 3D diffusion magnetic resonance imaging.

Computer-implemented method for recording MR data, including: executing a MR sequence having a sequence segment maintained in a steady state by regular excitation modules, each excitation module including an excitation pulse; for each excitation module, providing: a first read-out time window for measuring MR data of a free induction decay; and a second read-out time window, occurring after a last excitation module by at least a duration of the first read-out time window, the last excitation module acting as a refocusing module for the penultimate excitation module, wherein both read-out time windows follow an excitation module and are used to measure MR data of a spin echo; and outputting, in a preparation period between a pair of excitation modules comprising a beginning excitation module and a concluding excitation module that follow one another in the MR sequence, a fat saturation module including a RF fat saturation pulse.

In contrast-enhanced MRI, a visualization capability of a tissue which a contrast agent reaches is increased, and overall imaging time is shortened. An imaging unit of an MRI apparatus includes a gradient echo pulse sequence for acquiring a T1 weighted image including a fat saturation pulse, and a control unit performs control to generate images of a plurality of phases having different arrival positions of a contrast agent by repeating the pulse sequence for a predetermined time from administration of the contrast agent to the subject by the imaging unit. At this time, a preparation pulse that suppresses a signal from a contrast agent present outside a target tissue (cell) is added prior to a pulse sequence, in a phase immediately before reaching the target tissue.

The present invention discloses a 2D echo planar diffusion imaging method, medium and device based on dual-frequency orthogonal gradients. The present invention suppresses the partial volume effect caused by cerebrospinal fluid in the ventricular region by applying a pulse gradient orthogonal to the cosine oscillation gradient. The imaging sequence includes the following steps: first, suppressing the fat signal by a fat saturation module; second, using a diffusion coding module, embedding a pair of trapezoidal cosine oscillation gradients into the left and right sides of the refocusing radio frequency pulse, and at the same time applying another pair of pulse gradients of the same length in the orthogonal direction of the oscillation gradient to suppress free water with a higher diffusion rate; finally, using the echo planar imaging coding readout method to collect signals. The diffusion imaging sequence based on dual-frequency orthogonal gradients can effectively realize the accurate measurement of the time-dependent apparent diffusion coefficient under the clinical scanning system, which is conducive to the clinical transformation of microstructure imaging technology based on time-dependent diffusion magnetic resonance.