Abstract: Featured are methods for magnetic resonance imaging of a volume, such a volume having susceptibility-generating objects or interfaces having susceptibility mismatches therein. Such a method includes selectively visualizing one of susceptibility-generating objects or interfaces having susceptibility mismatches as hyperintense signals, where such visualizing includes controlling variable imaging parameters so as to control a geometric extent of a signal enhancing effect, m more particular aspects of the present invention, such selectively visualizing includes attenuating or essentially suppressing signals from fat and/or water, namely on-resonant water protons, so as to thereby enhance a signal(s) associated with magnetic susceptibility gradient(s). Also featured are MRI systems, apparatuses and/or applications programs for execution on a computer system controlling the MRI data acquisition process embodying such methods.

Abstract: A method for tracking a needle along a path under real-time magnetic resonance imaging (MRI) guidance includes extracting a candidate needle artifact region from a plurality of incoming MR images of a needle inside biological tissue, determining an initial needle direction vector from the candidate needle artifact region in each of the plurality of incoming needle images, determining an initial needle base point from an intersection of the needle direction vector with a first incoming needle image, and an initial needle tip point from an intersection of the needle direction vector with a last incoming needle image, and tracking said needle by minimizing a cost function of the initial base point and initial direction vector to calculate an updated base point and updated direction vector. The updated base point and direction vector are used to visualize the advance of the needle along the path through the biological tissue.

Abstract: A method for determining a concentration of fat within a region of a subject includes acquiring at least three gradient echo images from at least two different flip angles. The first and third images occur at an in-phase time when resonance signals of fat and water are in-phase with one another. The second images occur at an opposed-phase time when the resonance signals of fat and water are 180° out of phase with one another. T2* and T1 relaxation time maps are approximated based on the acquired images. Fat and water signals are distinguished based on observed relative signal phase. The amplitude of the fat and water signals are modulated using the T2* and T1 relaxation time maps. A ratio between fat and water signals for one or more voxels of the images is calculated based on the amplitude modulated fat and water signal images.

Abstract: A method for tracking a needle along a path under real-time magnetic resonance imaging (MRI) guidance includes extracting a candidate needle artifact region from a plurality of incoming MR images of a needle inside biological tissue, determining an initial needle direction vector from the candidate needle artifact region in each of the plurality of incoming needle images, determining an initial needle base point from an intersection of the needle direction vector with a first incoming needle image, and an initial needle tip point from an intersection of the needle direction vector with a last incoming needle image, and tracking said needle by minimizing a cost function of the initial base point and initial direction vector to calculate an updated base point and updated direction vector. The updated base point and direction vector are used to visualize the advance of the needle along the path through the biological tissue.

Abstract: Featured are methods for magnetic resonance imaging of a volume, such a volume having susceptibility-generating objects or interfaces having susceptibility mismatches therein. Such a method includes selectively visualizing one of susceptibility-generating objects or interfaces having susceptibility mismatches as hyperintense signals, where such visualizing includes controlling variable imaging parameters so as to control a geometric extent of a signal enhancing effect, m more particular aspects of the present invention, such selectively visualizing includes attenuating or essentially suppressing signals from fat and/or water, namely on-resonant water protons, so as to thereby enhance a signal(s) associated with magnetic susceptibility gradient(s). Also featured are MRI systems, apparatuses and/or applications programs for execution on a computer system controlling the MRI data acquisition process embodying such methods.

Abstract: Featured are methods for magnetic resonance imaging of a volume, such a volume having susceptibility-generating objects or interfaces having susceptibility mismatches therein. Such a method includes selectively visualizing one of susceptibility-generating objects or interfaces having susceptibility mismatches as hyperintense signals, where such visualizing includes controlling variable imaging parameters so as to control a geometric extent of a signal enhancing effect, m more particular aspects of the present invention, such selectively visualizing includes attenuating or essentially suppressing signals from fat and/or water, namely on-resonant water protons, so as to thereby enhance a signal(s) associated with magnetic susceptibility gradient(s). Also featured are MRI systems, apparatuses and/or applications programs for execution on a computer system controlling the MRI data acquisition process embodying such methods.

Abstract: A method for determining a concentration of fat within a region of a subject includes acquiring at least three gradient echo images from at least two different flip angles. The first and third images occur at an in-phase time when resonance signals of fat and water are in-phase with one another. The second images occur at an opposed-phase time when the resonance signals of fat and water are 180° out of phase with one another. T2* and T1 relaxation time maps are approximated based on the acquired images. Fat and water signals are distinguished based on observed relative signal phase. The amplitude of the fat and water signals are modulated using the T2* and T1 relaxation time maps. A ratio between fat and water signals for one or more voxels of the images is calculated based on the amplitude modulated fat and water signal images.

Abstract: Featured are methods for magnetic resonance imaging of a volume, such a volume having susceptibility-generating objects or interfaces having susceptibility mismatches therein. Such a method includes selectively visualizing one of susceptibility-generating objects or interfaces having susceptibility mismatches as hyperintense signals, where such visualizing includes controlling variable imaging parameters so as to control a geometric extent of a signal enhancing effect, m more particular aspects of the present invention, such selectively visualizing includes attenuating or essentially suppressing signals from fat and/or water, namely on-resonant water protons, so as to thereby enhance a signal(s) associated with magnetic susceptibility gradient(s). Also featured are MRI systems, apparatuses and/or applications programs for execution on a computer system controlling the MRI data acquisition process embodying such methods.