Multi-contrast delayed enhancement cardiac magnetic resonance imaging

摘要

A series of MR image frames are acquired that depict a subject's heart at successive cardiac phases. Delayed enhancement of infarcted myocardium is depicted in some of the image frames by administering a contrast agent prior to data acquisition. Data acquisition is performed in a single breath hold by producing an RF inversion pulse followed by segments of SSFP pulse sequences during a succession of cardiac gated heart beats. The acquired MR image frames depict contrast between blood, viable myocardium and nonviable myocardium, and they depict left ventricle wall thickness and wall thickening throughout the cardiac cycle.

主权项

1. A method for producing a series of cardiac gated magnetic resonance images of a subject's heart, the steps comprising:
a) administering a contrast agent to the subject; b) producing a gating signal that indicates the start of the subject's cardiac cycle; c) producing a radio frequency (RF) inversion pulse that inverts spin magnetization throughout a field of view a preset time after the gating signal is produced; d) acquiring k-space data as a series of data segments at successive cardiac phases after the RF inversion pulse is produced using a plurality of steady-state free precession (SSFP) pulse sequences during a time period in which the inverted spin magnetization recovers such that some data segments in the series of data segments are acquired when tissue contrast is changing and other data segments in the series of data segments are acquired when tissue contrast is no longer substantially changing; e) repeating steps b) through d) until a desired amount of k-space data is acquired in each data segment; f) reconstructing a series of image frames depicting the heart at a succession of cardiac phases using the k-space data acquired in the series of data segments, and in which images in the series of image frames reconstructed from the data segments acquired when tissue contrast is changing depict a time-varying tissue contrast of the heart, and in which images in the series of image frames reconstructed from the data segments acquired when tissue contrast is no longer substantially changing depict cardiac wall motion; and g) producing a T1* map by:
i) determining for a given pixel location in the T1* map, a T1* value by fitting magnitude values from corresponding pixel locations in the series of image frames reconstructed in step f) to a signal model that relates magnitude values to T1*; andii) setting magnitude values for each given pixel location in the T1* map to the corresponding T1* value determined in step g)i).