US 2021/0333347 A1 · MAGNETIC RESONANCE IMAGING APPARATUS AND IMAGE PROCESSING METHOD

Abstract

Provided is a magnetic resonance imaging apparatus with no occurrence of artifacts, even after noise removal by applying Wavelet transform to a zero-fill reconstructed image. Nuclear magnetic resonance signals acquired by the magnetic resonance imaging apparatus are processed to perform reconstruction with a reconstruction matrix extended by zero-filling an acquisition matrix, and then a zero-fill reconstructed image is produced. This reconstructed image is subjected to an iterative operation combining the Wavelet transform and L1 norm minimization to remove noise. Before the noise removal, a pre-processing is performed to change the reconstruction matrix size so that an artifact does not occur in the image after noise removal, an artifact portion appears outside the reconstruction matrix after the noise removal, or cutting out is performed so that no artifact appears after the noise removal. The matrix size is restored to its original size in the post-processing after the noise removal.

Claims13

Dependent claims

A magnetic resonance imaging apparatus comprising,

a measuring unit having a transmission unit configured to transmit an RF magnetic field pulse to a subject disposed in a static magnetic field, a receiving unit configured to receive a nuclear magnetic resonance signal generated by the subject, and a gradient magnetic field generator for providing a gradient magnetic field to the static magnetic field, and
a computer configured to perform an operation on the nuclear magnetic resonance signal received by the receiving unit, wherein
the computer comprises an image generator configured to process the nuclear magnetic resonance signal being received to generate a reconstructed image with a reconstruction matrix obtained by extending an acquisition matrix by zero-filling, and
a noise remover configured to remove noise from the reconstructed image, wherein
the noise remover performs noise removal after changing the size of a matrix of the reconstructed image, and performs a process of restoring the matrix of the reconstructed image after the noise removal, to the reconstruction matrix.

2 more elements

A magnetic resonance imaging apparatus comprising,

a measuring unit having a transmission unit configured to transmit an RF magnetic field pulse to a subject disposed in a static magnetic field, a receiving unit configured to receive a nuclear magnetic resonance signal generated by the subject, and a gradient magnetic field generator for providing a gradient magnetic field to the static magnetic field, and
a computer configured to perform an operation on the nuclear magnetic resonance signal received by the receiving unit, wherein
the computer comprises an image generator configured to process the nuclear magnetic resonance signal being received to generate a reconstructed image with a reconstruction matrix obtained by extending an acquisition matrix by zero-filling, and a noise remover configured to remove noise from the reconstructed image, wherein
the noise remover comprises an artifact prediction unit configured to predict a characteristic of an artifact caused by generating the reconstructed image in the image generator and by removing noise, and a window function creating unit configured to create a window function for eliminating the predicted artifact, and the artifact is eliminated by using the window function.

1 more element

Dependencies are inferred from the claim text.

Magnetic resonance imaging apparatus and image processing method

Life of this patent

Magnetic resonance imaging apparatus and image processing method

Life of this patent

Abstract

Claims13