Abstract: A method for musculoskeletal tissue segmentation used in magnetic resonance imaging (MRI) is provided. MRI image data is collected using at least two different contrast mechanisms. Voxel values from data from each contrast mechanism are used as elements of a feature vector. The feature vector is compared with classification boundaries to classify musculoskeletal tissue type of the voxel. The previous two steps are repeated for a plurality of voxels. An image is generated from the classified musculoskeletal tissue types for the plurality of voxels to provide a musculoskeletal segmentation image.

Abstract: A method for 3D magnetic resonance imaging (MRI) with slice-direction distortion correction is provided. One or more selective cross-sections with a thickness along a first axis is excited using a RF pulse with a bandwidth, wherein a selective cross-section is either a selective slice or selective slab. A refocusing pulse is applied to form a spin echo. One or more 2D encoded image signals are acquired with readout along a second axis and phase encoding along a third axis. Slice-direction distortion is corrected by resolving the position by resolving the frequency offset.

Abstract: A method for 3D magnetic resonance imaging (MRI) with slice-direction distortion correction is provided. One or more selective cross-sections with a thickness along a first axis is excited using a RF pulse with a bandwidth, wherein a selective cross-section is either a selective slice or selective slab. A refocusing pulse is applied to form a spin echo. One or more 2D encoded image signals are acquired with readout along a second axis and phase encoding along a third axis. Slice-direction distortion is corrected by resolving the position by resolving the frequency offset.

Abstract: A method for musculoskeletal tissue segmentation used in magnetic resonance imaging (MRI) is provided. MRI image data is collected using at least two different contrast mechanisms. Voxel values from data from each contrast mechanism are used as elements of a feature vector. The feature vector is compared with classification boundaries to classify musculoskeletal tissue type of the voxel. The previous two steps are repeated for a plurality of voxels. An image is generated from the classified musculoskeletal tissue types for the plurality of voxels to provide a musculoskeletal segmentation image.

Abstract: The acquisition of multiple images at slightly different time shifts from the spin echo (or from TE=0 for gradient echo sequences), allows the separation of on-resonance spins from off-resonance spins by encoding this information in the received signal. The excitation pulse can be a standard broadband excitation that will excite all spins. The separation of on- and off-resonance spins is then performed on the received signal. The polar and equatorial lobes of a magnetic particle such as SPIO produce signals from excited water molecules near the particle which are frequency offset above and below the frequency of signals from water molecules unaffected by the particle.

Abstract: The tuning of an interventional receiver coil for magnetic resonance imaging signals is tuned by coupling a varactor tuned circuit with the coil and adjusting a DC voltage applied to the varactor to alter the tuning whereby the coil is tuned to the Larmor frequency of the MRI signals.

Abstract: The present invention provides an apparatus and method for viewing medical images on a handheld computer. After medical images are obtained, they could be either be transferred directly to a handheld computer or indirectly via a computer. The medical images could also be transferred from one handheld computer to another handheld computer. A conversion of medical images is performed to convert the image from a standard format to an appropriate format for the selected handheld computer. One or more interactive tools are provided for displaying the one or more converted medical images on the handheld computer. An exemplary embodiment is provided that shows the conversion of a DICOM format medical image so that it could be displayed and viewed on a personal digital assistant. The advantage of the present invention is that it allows one to obtain, view and analyze medical images completely wireless and mobile on a personalized handheld computer.

Abstract: A coil for magnetic resonance imaging includes at least two spaced electrodes positionable within an object in proximity to a region of interest with feed wires coupling the electrodes to a signal detector. The electrodes and feed wire cooperatively function with tissue and fluid of the object to form an RF signal detecting coil. The electrodes can be needles or rings around the circumference of a catheter or electrodes which extend from and are retractable within a catheter.