Single-scan in vivo lactate editing with complete lipid and water suppression by selective multiple-quantum-coherence transfer (Sel-MQC) with application to tumors.

A novel single-scan selective homonuclear multiple-quantum coherence-transfer technique, Sel-MQC, is presented that achieves lactate editing with complete lipid and water suppression. The method is suitable for studying tissues with high fat content and those subject to substantial motion. Frequency-selective excitation is employed to selectively prepare lactate into its multiple-quantum states; lipid and water are left in the single-quantum modes and eliminated by the multiple-quantum selection gradients. The efficiency of lipid suppression is monitored by a 2D Sel-MQC experiment which separates lipid and lactate along the multiple-quantum-evolution dimension. The spatial distribution of lactate can be imaged by the spectroscopic imaging version of Sel-MQC. Sel-MQC sequences were demonstrated both in phantoms and in vivo, using subcutaneously implanted murine EMT6 tumors.