Respiratory Gated SPAMM Sequence for Magnetic Resonance Cardiac Tagging

SPAMM (Spatial Modulation of Magnetization) sequences for tissue tagging suffer from fading of the tags due to tissue T1 decay. This fading is especially important in cardiac imaging, since it affects the frames acquired in the second half of the cardiac cycle. On the other hand, breath-hold sequences are difficult to hold along a prolonged exploration. We present an alternative SPAMM sequence with respiratory gating that alleviates the mentioned drawbacks. We compare images acquired with the sequence provided by the manufacturer in a Philips Intera 1.5T scanner with images acquired with the proposed sequence. Normal volunteers (n=5) have been scanned with each sequence. The most remarkable result is that tissue-tag contrast almost doubles in the last frames with the proposed sequence as compared to the sequence supplied by the manufacturer.