Fujifilm Healthcare Corporation

Fujifilm Corporation

Hiroki Shoji

Toru Shirai

Shinji Kurokawa

Kosuke Ito

Hikaru Hanada

Yasuhiro Kamada

Takenori Murase

Tomoki Amemiya

Atsuro Suzuki

Yukio Kaneko

Keisuke Nishio

Appropriate processing is executed in a method for excluding body motion data and image reconstruction according to a type and a characteristic of a body motion, so as to reduce an influence of the body motion, and prevent deterioration of image quality caused by exclusion of data generated during the body motion. An MRI apparatus includes a processing determination unit that collects k-space data and acquires body motion information from a sensor capable of detecting not only a respiratory motion but also general body motions, analyzes the body motion information obtained by the sensor, and branches and executes processing for subsequent data collection and image reconstruction according to the analysis result. The MRI apparatus determines, based on a temporal characteristic such as a duration and a frequency, and a spatial characteristic of the body motion, particularly a generation pattern in a k-space, body motion data to be excluded, and executes image reconstruction suitable for k-space data after exclusion of the body motion data.

Magnetic resonance imaging apparatus and control method thereof

Provided is a method for performing reconstruction and noise removal with high accuracy on various undersampling patterns including equidistant undersampling. An image processing unit that processes measurement data acquired by an MRI apparatus performs image reconstruction by using measurement data on respective channels measured in a predetermined undersampling pattern and sensitivity distributions of respective reception coils. At this time, denoising of a reconstructed image and a calculation for maintaining consistency between original measurement data and the measurement data on the respective channels created from denoised images are sequentially processed. Accordingly, image restoration and denoising with high accuracy are possible without depending on the undersampling pattern.

Magnetic resonance imaging apparatus, image processing apparatus, and image processing method

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.

Magnetic resonance imaging apparatus and image processing method

During obtaining a sensitivity distribution in a k-space, data based on which the sensitivity distribution is obtained is expanded with a mirror image to create an expanded image to prevent spectrum leakage, and the sensitivity distribution is stably calculated. During obtaining the sensitivity distribution in the k-space, image data based on which the sensitivity distribution is obtained is inverted as a mirror image to be made into the expanded image, the expanded image is transformed into k-space data, and a frequency component (frequency space data) of the sensitivity distribution is calculated. A region corresponding to the original image data is clipped from the calculated frequency space data, and the sensitivity distribution is obtained.

Magnetic resonance imaging device and sensitivity distribution calculation program

Growing community of inventors

Chiba, Japan

Hiroki Shoji