A system for generating MR images for segmentation and/or use in correcting attenuation in subsequent images using other modalities (e.g., PET, SPECT, etc.) is described. A surrogate soft tissue device is provided and positioned on the patient near the artifact source to provide a surrogate soft tissue boundary that can be imaged and interpreted during segmentation to mitigate the deleterious effects of a local susceptibility artifact in the MR image.

In the field of obesity related disease, identification of patients with nonalcoholic steatohepatitis (NASH) would be useful to counsel them more intensively on diet and lifestyle changes and propose new pharmacological treatments. As a consequence, the inventors worked on a method for post-processing images of a region of interest of the liver for reconstructing a map of the internal magnetic susceptibility by using a Bayesian regularization approach to inverse the internal magnetic field. Such method can be implemented on computer and provides better results than other known methods for obesity related disease. This method may be applied for predicting that a subject is at risk of suffering from such disease, diagnosing a disease, identifying a therapeutic or a biomarker and screening compounds useful as a medicine.

Improved magnetic resonance imaging systems, methods and software are described including a low field strength main magnet, a gradient coil assembly, an RF coil system, and a control system configured for the acquisition and processing of magnetic resonance imaging data from a patient while utilizing a sparse sampling imaging technique.

A method is provided for magnetic resonance (MR) imaging near metal, including acquiring an image at a first magnetic field from a subject that includes a metal object, acquiring an image at a second magnetic field, and combining the images to provide a corrected image with reduced metal distortion. An MR imaging system for measuring near metal is also provided including a superconducting magnet to provide a magnetic field, a power supply for a current to ramp the magnetic field, a cryocooler in contact with the superconducting magnet, a magnetic field controller programmed to ramp the main magnetic field by adjusting the current generated by the power supply, a radio frequency system for transmitting and receiving signals, and a data acquisition and processing system to receive the MR signals, generate image data sets and combine the image data sets to provide a corrected image having a reduced metal distortion.

Quantitative susceptibility mapping methods, systems and computer-accessible medium include generating images of tissue magnetism property from complex magnetic resonance imaging data using the Bayesian inference approach. The tissue magnetism images is then used to monitor remyelination, such as remyelination in multiple sclerosis patients in response to therapy. Multiple sclerosis lesions defined on magnetic resonance imaging are further characterized on tissue magnetism images into hyperintense, isointense and hypointense parts for measuring remyelination. Thus, magnetic susceptibility information and other tissue properties associated with at least one structure are determined.

It is an object of the invention to improve quality assurance when using MRI images for radiotherapy treatment planning. This object is achieved by a treatment plan evaluation tool A configured for calculating a quality indicator for a radiotherapy treatment plan. The radiotherapy treatment plan originates from a planning image, wherein the planning image is an MRI image acquired under a presence of a main magnetic field having a magnetic field inhomogeneity. The treatment plan evaluation tool is further configured to receive information about the magnetic field inhomogeneity and the treatment plan evaluation tool is further configured to calculate the quality indicator based on the information about the magnetic field homogeneity.

Accuracy degradation due to a signal loss is reduced, and susceptibility is calculated with high accuracy where, by using an MRI, at least one echo is acquired where spatial magnetic field inhomogeneity is reflected, and a complex image is calculated from the acquired echo. Three masks are calculated from the calculated complex image; a low-signal region mask representing a low signal region, a first high-signal region mask representing a high signal and high fat content region, and a second high-signal region mask representing a high signal and low fat content region. In calculating a susceptibility image from a frequency image or a magnetic field image generated from the complex image, the susceptibility image is obtained under the constraint that a region defined by the low-signal region is set as a background and the susceptibility of the region defined by the second high-signal region mask is set to a specific value.

In a method and magnetic resonance (MR) apparatus for acquiring MR data from a volume of an object in which first and second excitable spin types are present that differ in their Larmor frequencies by a chemical shift, an MR sequence with at least one radio-frequency pulse sequence selectively excites the first spin type or selectively suppresses MR signals of the second spin type. A B0 map describing the basic field distribution in a region of interest of the volume is established. First and second items of distribution information, which respectively describe the spectral distribution of Larmor frequencies of the first and second spin types, are derived from the B0 map. A pulse sequence parameter that describes the excitation spectrum of the radio-frequency pulse sequence is optimized based on the items of distribution information, with regard to a quality criterion that optimizes selective excitation and/or suppression.

In the field of obesity related disease, identification of patients with nonalcoholic steatohepatitis (NASH) would be useful to counsel them more intensively on diet and lifestyle changes and propose new pharmacological treatments. As a consequence, the inventors worked on a method for post-processing images of a region of interest of the liver for reconstructing a map of the internal magnetic susceptibility by using a Bayesian regularization approach to inverse the internal magnetic field. Such method can be implemented on computer and provides better results than other known methods for obesity related disease. This method may be applied for predicting that a subject is at risk of suffering from such disease, diagnosing a disease, identifying a therapeutic or a biomarker and screening compounds useful as a medicine.

A technology of improving image quality of a calculation image or parameter estimation accuracy even in a case where a method of simultaneously generating calculation images of a plurality of parameters is used is provided. Thus, by utilization of a reconstructed image in an optimal resolution of each parameter to be estimated, a value of the parameter is estimated and a calculation image that is a distribution of the value of the parameter is acquired. A reconstructed image in an optimal resolution is acquired by adjustment of a resolution of a reconstructed image acquired in an optimal resolution of an estimation parameter with the highest optimal resolution among parameters to be estimated in scanning. Alternatively, in scanning, only a reconstructed image used for calculation of a predetermined parameter to be estimated is acquired in an optimal resolution of the parameter to be estimated.