Abstract: An improved method and system for identifying and displaying related images obtained during an examination is disclosed. Each image includes both pixel data, corresponding to the image to be displayed, and location information, defining a relationship between the pixel data and a reference point. During a review of the images, a physician may identify an abnormality or particular region of interest in one image. The location information corresponding to the position identified by the physician within the image is obtained from the image file. Having identified location information for a particular location on the first image, the system analyzes the location information corresponding to the pixel data for each of the other stored images to identify any other image that intersects the identified location. All images that intersect the identified location may then be displayed adjacent to the first image for inspection by the physician.

Abstract: An improved method and system for identifying and displaying related images obtained during an examination is disclosed. Each image includes both pixel data, corresponding to the image to be displayed, and location information, defining a relationship between the pixel data and a reference point. During a review of the images, a physician may identify an abnormality or particular region of interest in one image. The location information corresponding to the position identified by the physician within the image is obtained from the image file. Having identified location information for a particular location on the first image, the system analyzes the location information corresponding to the pixel data for each of the other stored images to identify any other image that intersects the identified location. All images that intersect the identified location may then be displayed adjacent to the first image for inspection by the physician.

Abstract: Embodiments presented herein provide apparatus and methods for imaging-assisted determination of pressure gradient of blood flow across a valve orifice in a cardiovascular circuit without the use of velocity data measured at the valve orifice. An embodiment of the methods comprise creating an image of a valve orifice, creating a planimeter slice from the image of the valve orifice including a trace of the perimeter of the valve orifice, determining the valve orifice area by determining the area contained within the trace, determining the instantaneous flow rate through the valve orifice based on bulk flow data away from the valve, and determining the instantaneous pressure gradient across the valve orifice from the valve orifice area and the instantaneous flow rate.

Abstract: Embodiments presented herein provide apparatus and methods for imaging-assisted determination of pressure gradient of blood flow across a valve orifice in a cardiovascular circuit without the use of velocity data measured at the valve orifice. An embodiment of the methods comprise creating an image of a valve orifice, creating a planimeter slice from the image of the valve orifice including a trace of the perimeter of the valve orifice, determining the valve orifice area by determining the area contained within the trace, determining the instantaneous flow rate through the valve orifice based on bulk flow data away from the valve, and determining the instantaneous pressure gradient across the valve orifice from the valve orifice area and the instantaneous flow rate.

Abstract: A system and method for MR imaging is disclosed that includes displaying a series of MR images of an ROI in real-time and localizing a slice within the ROI. The method also includes using a parallel imaging technique to acquire gated MR data from the localized slice and reconstructing a prescribed fixed number of gated MR images of the localized slice.

Abstract: A system and method for MR imaging is disclosed that includes displaying a series of MR images of an ROI in real-time and localizing a slice within the ROI. The method also includes using a parallel imaging technique to acquire gated MR data from the localized slice and reconstructing a prescribed fixed number of gated MR images of the localized slice.

Abstract: A system and method for MR imaging is disclosed that includes displaying a series of MR images of an ROI in real-time and localizing a slice within the ROI. The method also includes using a parallel imaging technique to acquire gated MR data from the localized slice and reconstructing a prescribed fixed number of gated MR images of the localized slice.

Abstract: A method and apparatus is disclosed for MR perfusion acquisition using a notched RF saturation pulse. In acquiring such MR data, a volume of slice locations is selected in which MR data is to be acquired. Each given slice is prepared with a notched RF saturation pulse which has a stop-band between a pair of pass-bands. The stop-band is designed to not affect the spins in the next slice in which MR data is to be acquired thereby effectively increasing the TI and increasing SNR and contrast simultaneously. Since the notched saturation pulse saturates all the spins outside of the notched stop-band, the blood in the ventricular chamber is effectively saturated so that the resulting perfusion images have blood pool suppression. Additionally, the use of a 90° presaturation RF pulse provides a high level of immunity to the effects of arrhythmias or other variations in the patient's heart rate.

Abstract: A method, and related apparatus, for suppressing the magnetic resonance signal to an experimentally adjustable depth by applying a spatially inhomogeneous field between the slice-select pulse and the data acquisition. Eliminating the signal from near surface regions allows one to shrink the field of view of an image without introducing aliasing artifacts, thereby improving the image's resolution or decreasing imaging time. Experimental tests on a phantom and a human subject indicate that the depth of signal suppression may be continuously varied to depths of over 80 millimeters with modest requirements on power supplies, pulse sequences, and materials.

Abstract: A system and method for arterial and venous discrimination in MR venography is disclosed. By setting a noise level in the phase image (that is proportional to the velocity encoding value) at a threshold level between that of the arterial signals and the venous signals during the diastole portion of the cardiac cycle and acquiring a phase contrast MR image during the diastole portion, the arterial signals are effectively suppressed and a venous only image can be reconstructed. Post-processing steps are disclosed which can alternatively provide an arterial only image. By separately reconstructing a magnitude image and a phase image map to produce a magnitude image and a phase image, a masking module can create an output displaying venous only or arterial only images based on a user selection. The present invention allows for a complete noninvasive angiography exam to be completed within approximately 30 minutes.

Abstract: A method is disclosed to reconstruct multiphase MR images that accurately depict the entire cardiac cycle. A segmented, echo-planar imaging (EPI) pulse sequence is used to acquire data continuously during each cardiac cycle. Images are retrospectively reconstructed by selecting views from each heartbeat based on cardiac phase.

Abstract: An MRI scan is conducted in which velocity encoded NMR data is acquired for a slice through the heart. Velocity images and magnitude images are reconstructed at multiple cardiac phases and masks are formed using the magnitude images. The masks are applied to the velocity images to isolate the left ventricle, and rigid body motion is calculated and subtracted from the masked velocity images to indicate deformation of the left ventricle.

Abstract: A method is disclosed to reconstruct multiphase MR images that accurately depict the entire cardiac cycle. A segmented, gradient-recalled-echo sequence is modified to acquire data continuously. Images are retrospectively reconstructed by selecting views from each heartbeat based on cardiac phase rather than the time elapsed from the QRS complex. Cardiac phase is calculated using a model that compensates for beat-to-beat heart rate changes.

Abstract: A nuclear magnetic resonance method is provided for monitoring and imaging the exchange of magnetization between protons in free water and protons in a relatively immobilized pool of protons in a sample. The method provides a new form of contrast for nuclear magnetic resonance imaging of samples such as biological tissues, polymers, and geological samples.