MRI device and method

Abstract

An MRI apparatus includes an imaging signal acquisition unit, a motion signal acquisition unit, a motion amount determination unit, a motion correction unit and an image reconstruction unit. The imaging signal acquisition unit acquires MR signals as imaging signals. The motion signal acquisition unit repetitively acquires MR signals having a phase encoding amount less than that of the imaging signals as motion signals. The motion amount determination unit obtains a motion amount using the motion signals. The motion correction unit performs correction processing of the imaging signals in accordance with the motion amount. The image reconstruction unit reconstructs an image using the imaging signals after the correction processing.

Description

technical field [0001] The invention relates to a magnetic resonance imaging device and a magnetic resonance imaging method, which generate a gradient magnetic field on an imaging area formed in a static magnetic field, and cause magnetic resonance to occur on nuclear spins in a target set in the imaging area by emitting radio frequency signals , and reconstructing an image of said target by using nuclear magnetic resonance signals generated due to excitation, and more specifically, to a magnetic resonance imaging apparatus and a magnetic resonance imaging method in which the influence of target motion on the image is reduced by correction . Background technique [0002] An MRI (Magnetic Resonance Imaging) device is a device that generates gradient magnetic fields through gradient coils on an imaging zone of a target set within a cylindrical static field magnet used to generate a static magnetic field, by transmitting An RF (Radio Frequency) signal causes magnetic resonance...

AI Technical Summary

Problems solved by technology

[0013] However, this method of navigating signals for acquiring navigation signals under a condition different from the data acquisition conditions used for imaging has two main problems

[0014] The first problem is that the respiration-related displacement of the imaging target region (heart) and the displacement of the region observed by the navigation signal (diaphragm) are correlated, but not identical to each other

Therefore, the displacement of the heart is estimated from the displacement of the diaphragm, which is one reason for reduced accuracy

In addition, even in the same target, the ratio between the amount of displacement of the heart related to breathing and the amount of displacement of the diaphragm differs depending on the individual and varies depending on the state of breathing, so it is difficult to obtain a stable image

[0015] The second problem is that the timing used to detect the signal from the diaphragm is very different from the timing used to detect the imaging signal

Therefore, the accuracy of motion detection is easily affected by non-moving areas, especially in imaging situations that require high precision, such as high-resolution imaging, the impact of non-moving areas on motion detection accuracy will be very problematic

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