Abstract: A system and method are disclosed to acquire high temporal resolution free-breathing cardiac MR images. The technique includes monitoring heart rate of a patient just prior to image acquisition to acquire a time period of an R—R interval, and using this time period from the heart rate monitoring to prospectively estimate future R—R intervals. The acquisition of MR data can then commence at any point in an R—R interval and extend for the time period recorded. The data acquisition can be segmented and acquired in successive R—R intervals, then combined to create high temporal resolution images.

Abstract: A method and apparatus is disclosed in which a two-tiered approach is taken to first grade a patient to identify the presence of any suspected stenosis, and then a second step is used to acquire more detailed information to grade the stenosis. The invention includes performing a screening study by acquiring a first MR image having a low resolution to scan a suspected stenosis region. After analyzing the first MR image to identify a suspected stenosis within the suspected stenosis region, a more detailed study is performed by acquiring a second MR image having a higher resolution than the first MR image to scan the identified suspected stenosis. If no lesions, or stenotic vessels, are identified after the first MR image, the second MR image need not be obtained.

Abstract: A system and method for shifting of motion based artifacts in images produced with an magnetic resonance imaging system configured to: select a segment of a plurality of segments comprising a selected number of k-space lines of k-space data for a temporal series and select a time interval from a plurality of time intervals for acquisition. The magnetic resonance imaging system is also configured to acquire N sets of k-space lines comprising every Nth k-space line of the segment for successive 1/N portions of said time interval and repeating the acquiring for successive sets of the N sets of k-space lines and wherein N is an integer greater than one. The acquisition is repeated for each time interval of the plurality of time intervals and for each segment of the plurality of segments. The k-spaced data are reconstructed employing a time-weighted average based on respective time of acquisition of the k-space lines.

Abstract: A method and apparatus-are disclosed for achieving suppression of blood pool signal to detect myocardial infarction using MR technology. An RF pulse sequence is applied that includes a notched inversion RF pulse designed to suppress blood pool in and around a region-of-interest. MR data is then acquired within the region-of-interest that not only has signals from normal myocardial tissue suppressed, but also has blood pool signal suppression to improve delineation of infarcted myocardium from the ventricular blood pool and normal myocardium.

Abstract: The present invention includes a method and apparatus for high sensitivity whole body scanning using MR imaging. The invention includes acquiring MR data as the patient moves through the iso-center of the magnet while providing interactive control for the operator to change scan parameters and table motion and direction. The technique allows efficient whole body scanning for fast screening of abnormalities while allowing operator control during the screening process to interrupt table motion and redirect the speed and direction of the table while also allowing control over the acquisition plane, number of sections imaged, inter-section spacing, and the scan location.

Abstract: A system and method for optimally imaging the peripheral vasculature is disclosed which includes defining a given number of scan stations along a patient's peripheral vasculature and initially injecting a relatively small amount of contrast agent into the patient to pass a test bolus through the patient's peripheral vasculature, and thereafter tracking the test bolus through the patient and adjusting the patient on a moveable table within the MR imaging device from one scan station to a next station to determine a maximum travel time that the test bolus takes to travel through each of the given number of scan stations. Additional contrast agent is then injected into the patient to pass an exam bolus through the patient's peripheral vasculature, and using the test bolus travel time, MR data can be acquired from each scan station while it is known that the exam bolus is present in that station to optimize image resolution.

Abstract: A system and method for shifting of motion based artifacts in images produced with an magnetic resonance imaging system configured to: select a segment of a plurality of segments comprising a selected number of k-space lines of k-space data for a temporal series and select a time interval from a plurality of time intervals for acquisition. The magnetic resonance imaging system is also configured to acquire N sets of k-space lines comprising every Nth k-space line of the segment for successive 1/N portions of said time interval and repeating the acquiring for successive sets of the N sets of k-space lines and wherein N is an integer greater than one. The acquisition is repeated for each time interval of the plurality of time intervals and for each segment of the plurality of segments. The k-spaced data are reconstructed employing a time-weighted average based on respective time of acquisition of the k-space lines.

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 apparatus are disclosed for quickly acquiring MR cardiac images in a time equivalent to a single breath-hold. MR data acquisition is partitioned into at least low and high spatial frequency views and segmented within each of the partitions such that multiple segments of MR data are acquired from each phase of the cardiac cycle for the low and high spatial frequency views. Acquisition of MR data in the low spatial frequency views is performed relatively more often than the acquisition of MR data in the high spatial frequency views. MR images are reconstructed using this variable temporal k-space sampling technique to produce volume images of the heart within a single breath-hold. Images can be acquired throughout the cardiac cycle at both diastole and systole that can be used for measuring ventricular volumes and ejection fractions. Single phase volume acquisitions can also be performed to assess myocardial infarction.

Abstract: A method and apparatus are disclosed for creating peripheral MR angiographic images and performing an MRA examination using an intravascular contrast agent in which MR data acquisition is optimized in the most distal stations in a multi-station acquisition. The technique includes administering a contrast agent into the blood stream of the patient, acquiring low spatial resolution MR images of the arterial vasculature, and tracking the passage of the contrast agent through the patient. The patient table is moved in response to the tracking. The technique continues to acquire low spatial resolution images at each of the proximal stations until the most distal station is reached where a high spatial resolution image data set is then acquired of preferentially arterial vascular structures. Higher spatial resolution images are then acquired in the proximal stations.

Abstract: A method and apparatus are disclosed for achieving suppression of blood pool signal to detect myocardial infarction using MR technology. An RF pulse sequence is applied that includes a notched inversion RF pulse designed to suppress blood pool in and around a region-of-interest. MR data is then acquired within the region-of-interest that not only has signals from normal myocardial tissue suppressed, but also has blood pool signal suppression to improve delineation of infarcted myocardium from the ventricular blood pool and normal myocardium.

Abstract: A method and apparatus are disclosed for achieving suppression of blood pool signal to detect myocardial infarction using MR technology. After administering a contrast agent into the blood stream of a patient, an RF pulse sequence is applied that includes a slice-selective inversion pulse to suppress normal myocardial tissue followed by a notched inversion RF pulse designed to suppress blood pool in and around the region-of-interest. MR data is then acquired within the region-of-interest that not only has signals from normal myocardial tissue suppressed, but also has blood pool signal suppression to improve delineation of infarcted myocardium from the ventricular blood pool and normal myocardium.

Abstract: The invention includes a technique for efficient multi-slice fast spin echo image acquisition with black blood contrast in cardiac imaging. The technique includes applying a non-selective inversion pulse, followed by a re-inversion pulse that is slice-selective over a region encompassing a plurality of slice selections. Execution of a series of RF excitation pulses with fast spin echo readout is timed such that signal from blood is near a null point before acquiring data for each spatial slice. For greater contrast consistency, the flip angles for the excitation pulses occurring before the null point can be reduced, and those occurring after the null point can be increased.

Abstract: A system and method are disclosed that use the steady-state free precessing (SSFP) technique for MR imaging to allow the acquisition of MR angiography images in which the acquisition is not time dependent upon the first passage of a contrast agent. The technique includes applying a pulse sequence with refocusing S− signals from a train of RF pulses to a desired field-of-view (FOV) in a patient in which a contrast bolus has been injected. An SSFP image of the desired FOV is acquired, together with an S− SSFP mask image of the desired FOV. The S− SSFP mask image is subtracted from the SSFP image in order to reconstruct an image with improved visualization of the arterial and venous structures and reduce mis-registration artifacts.

Abstract: A system and method for optimally imaging the peripheral vasculature is disclosed which includes defining a given number of scan stations along a patient's peripheral vasculature and initially injecting a relatively small amount of contrast agent into the patient to pass a test bolus through the patient's peripheral vasculature, and thereafter tracking the test bolus through the patient and adjusting the patient on a moveable table within the MR imaging device from one scan station to a next station to determine a maximum travel time that the test bolus takes to travel through each of the given number of scan stations. Additional contrast agent is then injected into the patient to pass an exam bolus through the patient's peripheral vasculature, and using the test bolus travel time, MR data can be acquired from each scan station while it is known that the exam bolus is present in that station to optimize image resolution.

Abstract: A system and method is disclosed for tracking a moving object using magnetic resonance imaging. The technique includes acquiring a scout image scan having a number of image frames and extracting non-linear motion parameters from the number of image frames of the scout image scan. The technique includes prospectively shifting slice location using the non-linear motion parameters between slice locations while acquiring a series of MR images. The system and method are particularly useful in tracking coronary artery movement during the cardiac cycle to acquire the non-linear components of coronary artery movement during a diastolic portion of the R-R interval.

Abstract: A system and method for optimally imaging the peripheral vasculature is disclosed which includes defining a given number of scan stations along a patient's peripheral vasculature and initially injecting a relatively small amount of contrast agent into the patient to pass a test bolus through the patient's peripheral vasculature, and thereafter tracking the test bolus through the patient and adjusting the patient on a moveable table within the MR imaging device from one scan station to a next station to determine a maximum travel time that the test bolus takes to travel through each of the given number of scan stations. Additional contrast agent is then injected into the patient to pass an exam bolus through the patient's peripheral vasculature, and using the test bolus travel time, MR data can be acquired from each scan station while it is known that the exam bolus is present in that station to optimize image resolution.

Abstract: A method and apparatus are disclosed for quickly acquiring MR cardiac images in a time equivalent to a single breath-hold. MR data acquisition is partitioned into at least low and high spatial frequency views and segmented within each of the partitions such that multiple segments of MR data are acquired from each phase of the cardiac cycle for the low and high spatial frequency views. Acquisition of MR data in the low spatial frequency views is performed relatively more often than the acquisition of MR data in the high spatial frequency views. MR images are reconstructed using this variable temporal k-space sampling technique to produce volume images of the heart within a single breath-hold. Images can be acquired throughout the cardiac cycle at both diastole and systole that can be used for measuring ventricular volumes and ejection fractions. Single phase volume acquisitions can also be performed to assess myocardial infarction.

Abstract: A system and method are disclosed that use the steady-state free precessing (SSFP) technique for MR imaging to allow the acquisition of MR angiography images in which the acquisition is not time dependent upon the first passage of a contrast agent. The technique includes applying a pulse sequence with refocusing S− signals from a train of RF pulses to a desired field-of-view (FOV) in a patient in which a contrast bolus has been injected. An SSFP image of the desired FOV is acquired, together with an S− SSFP mask image of the desired FOV. The S− SSFP mask image is subtracted from the SSFP image in order to reconstruct an image with improved visualization of the arterial and venous structures and reduce mis-registration artifacts.

Abstract: A method and apparatus are disclosed for achieving suppression of blood pool signal to detect myocardial infarction using MR technology. After administering a contrast agent into the blood stream of a patient, an RF pulse sequence is applied that includes a slice-selective inversion pulse to suppress normal myocardial tissue followed by a notched inversion RF pulse designed to suppress blood pool in and around the region-of-interest. MR data is then acquired within the region-ofinterest that not only has signals from normal myocardial tissue suppressed, but also has blood pool signal suppression to improve delineation of infarcted myocardium from the ventricular blood pool and normal myocardium.