Abstract: The present disclosure provides systems, apparatuses, and methods for generating images of the human body by solid-state magnetic resonance imaging. An example method can comprise receiving first imaging data at two or more echo times taken with a first radiofrequency configuration, receiving second imaging data at two or more echo times taken with a second radiofrequency configuration. An example method can comprise generating, based on at least the first imaging data and the second imaging data, two or more k-space datasets. An example method can comprise generating, based on at least the two or more k-space datasets, one or more images. The one or more images can comprise different image contrast.

Abstract: Provided are fuzzy distance transform-based methods, and an algorithm therefor, for analyzing digital images defining a volumetric region of an object from a digital image comprising finding a set of points in the image to generate a fuzzy subset, and calculating the fuzzy distance transform (FDT) of the fuzzy subset. The methods deal with the extraction of object features from digital images acquired at low resolution, specifically, the measurement of structural thickness distribution along an object. Targeted applications comprise, but are not limited to, the measurement of trabecular bone thickness in magnetic resonance or computed tomography images. Also provided are systems and device for utilizing the disclosed methods and algorithm to extract the object features from the digital images.

Abstract: The present invention comprises a system and method for analyzing trabecular bone structure. A means for scanning the trabecular bone using a magnetic resonance image (MRI) scanner generates bone image data, which is then processed including correcting, deshading and reducing noise in the image data.

Abstract: The present invention comprises a system and method for analyzing trabecular bone structure. A means for scanning the trabecular bone using a magnetic resonance image (MRI) scanner generates bone image data, which is then processed including correcting, deshading and reducing noise in the image data.

Abstract: The present indention comprises a system and method for analyzing trabecular bone structure. A means for scanning the trabecular bone using a magnetic resonance image (MRI) scanner generates bone image data, which is then processed including correcting, deshadi4 and reducing noise in the image data.

Abstract: The invention provides method, system and device for determining trabecular bone structure and strength by digital topological analysis, and offers, for the first time, a demonstration of superior associations between vertebral deformity and a number of architectural indices measured in the distal radius, thus permitting reliable and noninvasive detection and determination of the pathogenesis of osteoporosis. A preferred embodiment provides imaging in three dimension of a region of trabecular bone, after which the 3D image is converted into a skeletonized surface representation. Digital topological analysis is applied to the converted image, and each image voxel is identified and classified as a curve, a surface, or a junction; and then associated with microarchitectural indices of trabecular bone to quantitatively characterize the trabecular bone network. The invention is applicable in vivo, particularly on human subjects, or ex vivo.

Abstract: The present invention comprises a novel method, system and device for post-processing images, such as trabecular bone images, obtained by MRI, CT, or other image technologies, to provide increasing apparent image resolution and to alleviate the effects of partial volume blurring, which otherwise precludes accurate measurement of structures in the limited-resolution regime in which image voxel size is larger than the typical structural element to be resolved. Since acquiring images at increased resolution often exacts an unacceptable signal-to-noise penalty, methods and systems to alleviate the adverse effects of partial volume blurring are instrumental for the accurate measurement of architectural parameters in applications, such as predicting the mechanical competence of trabecular bone networks.

Abstract: Provided are fuzzy distance transform-based methods, and an algorithm therefor, for analyzing digital images defining a volumetric region of an object from a digital image comprising finding a set of points in the image to generate a fuzzy subset, and calculating the fuzzy distance transform (FDT) of the fuzzy subset. The invention deals with the extraction of object features from digital images acquired at low resolution, specifically, the measurement of structural thickness distribution along an object. Targeted applications comprise, but are not limited to, the measurement of trabecular bone thickness in magnetic resonance or computed tomography images. Also provided are systems and device for utilizing the disclosed methods and algorithm to extract the object features from the digital images.

Abstract: The invention provides method, system and device for determining trabecular bone structure and strength by digital topological analysis, and offers, for the first time, a demonstration of superior associations between vertebral deformity and a number of architectural indices measured in the distal radius, thus permitting reliable and noninvasive detection and determination of the pathogenesis of osteoporosis. A preferred embodiment provides imaging in three dimension of a region of trabecular bone, after which the 3D image is converted into a skeletonized surface representation. Digital topological analysis is applied to the converted image, and each image voxel is identified and classified as a curve, a surface, or a junction; and then associated with microarchitectural indices of trabecular bone to quantitatively characterize the trabecular bone network. The invention is applicable in vivo, particularly on human subjects, or ex vivo.

Abstract: The present invention comprises a novel method, system and device for post-processing images, such as trabecular bone images, obtained by MRI, CT, or other image technologies, to provide increasing apparent image resolution and to alleviate the effects of partial volume blurring, which otherwise precludes accurate measurement of structures in the limited-resolution regime in which image voxel size is larger than the typical structural element to be resolved. Since acquiring images at increased resolution often exacts an unacceptable signal-to-noise penalty, methods and systems to alleviate the adverse effects of partial volume blurring are instrumental for the accurate measurement of architectural parameters in applications, such as predicting the mechanical competence of trabecular bone networks.

Abstract: A method for noninvasively detecting osteoporosis in human subjects by means of NMR imaging is described. In the preferred embodiment, a series of images are acquired whereby the echo time TE is incremented until a predefined number of images, each differing in echo time, has been acquired. The images are then displayed, a region of interest (ROI) is selected and mean signal amplitudes are computed (block 46). The mean signal amplitude values are then used as inputs for the curve fitting procedure that computes T2* (block 48). The final step of the process compares the computed value of T2* with a normal baseline (block 50), which permits the subject to be classified as either normal or osteoporotic (block 52).

Abstract: Methods are provided for detecting and diagnosing osteoporosis using high-resolution NMR imaging of trabecular bone. One such method comprises the steps of obtaining high-resolution NMR imaging data indicative of the trabecular microstructure of a mass of bone, analyzing the imaging data to determine the density of the trabeculae of the bone, comparing the density thus obtained with reference trabecular density data, and determining on the basis of the comparison whether the subject is osteoporotic or normal. To determine trabecular density, bone volume can be computed as the area fraction of those pixels that by virtue of their characteristic pixel intensity can be assigned to bone. Trabecular thickness can be computed from the relative bone area in a region of interest divided by half the perimeter length, the perimeter length being the circumference of all bone islands observed in the region of interest.

Abstract: A time-of-flight magnetic resonance pulse sequence is used to detect arterial flow in an image of a slice of tissue. By timing the pulse sequence with the cardiac cycle and by holding the interpulse interval T.sub.I within time limits which ensure enhancement without significant change in flow velocity, arterial flow can be imaged. By triggering the pulse sequence from the QRS complex representative of the beginning of a body's cardiac cycle and delaying both excitation and detection pulses in the sequence by a time T.sub.A to ensure the pulses occur while flow is slow, MR signal data is generated which results in an image showing enhancement in the areas of arterial flow. In an extension of the foregoing, a second set of MR signal data is generated by adjusting the acquisition delay T.sub.A such that the excitation and detection pulses of a second sequence occur while arterial flow is fast.

Abstract: A method for rapid acquisition of NMR data utilizes excitation pulses which rotate the longitudinal magnetization through an angle smaller than 90.degree. to create a relatively large transverse magnetization component. A first 180.degree. RF pulse is then applied to create a spin-echo signal, while a second 180.degree. RF pulse is used to rapidly return to equilibrium the residual longitudinal magnetization inverted by the first pulse. The combination of the excitation and the second 180.degree. pulses permits the sequence repetition time to be shortened, thereby reducing the total data collection time. The method is applicable to, for example, two- and three-dimensional embodiments of Fourier transform and multiple-angle projection reconstruction NMR imaging methods.

Abstract: A method for visualizing in-plane flow utilizing an NMR pulse sequence to produce a plurality of odd and even spin-echo signals occurring respectively at echo delay times, T.sub.E, of 2.tau., 6.tau., 10.tau., etc., and 4.tau., 8.tau., 12.tau., etc. In the preferred embodiment, a fictitious spin-echo amplitude is calculated from the odd and even spin-echo signals at an echo delay time T.sub.E =0, for example. The calculated values for the odd spin-echo signals are lower than those calculated for the even spin-echo signals due to incomplete rephasing of the odd spin-echo signals in the presence of a read-out magnetic field gradient and flow. Subtraction of the calculated image pixel value of the odd spin-echo signals from the calculated pixel values of the even spin-echo signals results in a difference image which highlights the flowing nuclear spins. The image pixels due to stationary nuclear spins experience exact cancellation.

Abstract: A method is provided for accurate and rapid NMR imaging of computed T.sub.1 and M.sub.o (spin density) NMR images. The imaging data is acquired using a repetition of a sequence made up of RF and magnetic-field-gradient pulses. Each repetition of the sequence includes at least one step of reducing the net longitudinal magnetization in a predetermined region of the sample to zero. The longitudinal magnetization is allowed to at least partially recover prior to exciting nuclear spins in the predetermined region to produce at least one NMR spin-echo signal due primarily to the recovered magnetization. The spin-echo signal is sampled in the presence of a magnetic-field gradient for encoding spatial information.

Abstract: A method for measuring (direction and magnitude) and imaging fluid flow in an NMR sample. Nuclei in an imaging slice, transaxial, for example, to a direction of fluid flow, are first tagged (saturated or inverted) and then excited to produce a first NMR signal. This signal originates from tagged nuclei in the imaging slice and untagged nuclei which have partially or wholly replaced nuclei flowing out of the slice. Thereafter, nuclei are tagged in a second thicker sample region which includes the imaging slice and extends therefrom in a direction opposite to the fluid flow. The nuclei are again excited in the imaging slice. The NMR signal detected is again from the entire imaging slice but is due entirely to tagged nuclei (if the second slice is selected to have the appropriate thickness) and, therefore, has a smaller magnitude than the first signal. These signals are useful in measuring the fluid flow velocity.

Abstract: A method for rapid acquisition of NMR data utilizes excitation pulses which rotate the longitudinal magnetization through an angle smaller than 90.degree. to create a relatively large transverse magnetization component. A first 180.degree. RF pulse is then applied to create a spin-echo signal, while a second 180.degree. RF pulse is used to rapidly return to equilibrium the residual longitudinal magnetization inverted by the first pulse. The combination of the excitation and the second 180.degree. pulses permits the sequence repetition time to be shortened, thereby reducing the total data collection time. The method is applicable to, for example, two- and three-dimensional embodiments of Fourier transform and multiple-angle projection reconstruction NMR imaging methods.