Chemical exchange saturation transfer by intermolecular double-quantum coherence.

A number of contrast enhancement effects based on the use of intermolecular multiple-quantum coherences, or distant dipolar field effects are known. This phenomenon is characterized by the dependence on the mth power of the initial magnetization (where m is the coherence order used). In this paper, we describe the contrast enhancement based on chemical exchange saturation transfer and NOE, which is achieved by the use of intermolecular double-quantum coherences (iDQC). The method was validated using clinically relevant systems based on glycosaminoglycans and a sample of cartilage tissue, showing that the CEST contrast, as well as, NOE are enhanced by iDQC.