Comparison of B0 versus B0 and B1 field inhomogeneity correction for glycosaminoglycan chemical exchange saturation transfer imaging

PurposeThe study compares glycosaminoglycan chemical exchange saturation transfer (gagCEST) imaging of intervertebral discs corrected for solely B-0 inhomogeneities or both B-0 and B-1 inhomogeneities.MethodsLumbar intervertebral discs of 20 volunteers were examined with T-2-weighted and gagCEST imaging. Field inhomogeneity correction was performed with B-0 correction only and with correction of both B-0 and B-1. GagCEST effects measured by the asymmetric magnetization transfer ratio (MTRasym) and signal-to-noise ratio (SNR) were compared between both methods.ResultsSignificant higher MTRasym and SNR values were obtained in the nucleus pulposus using B-0 and B-1 correction compared with B-0-corrected gagCEST. The GagCEST effect was significantly different in the nucleus pulposus compared with the annulus fibrosus for both methods.ConclusionThe B-0 and B-1 field inhomogeneity correction method leads to an improved quality of gagCEST imaging in IVDs compared with only B-0 correction.