Chemical exchange saturation transfer magnetic resonance imaging of human knee cartilage at 3 T and 7 T
Article first published online: 27 DEC 2011
Copyright © 2011 Wiley Periodicals, Inc.
Magnetic Resonance in Medicine
Volume 68, Issue 2, pages 588–594, August 2012
How to Cite
Singh, A., Haris, M., Cai, K., Kassey, V. B., Kogan, F., Reddy, D., Hariharan, H. and Reddy, R. (2012), Chemical exchange saturation transfer magnetic resonance imaging of human knee cartilage at 3 T and 7 T. Magn Reson Med, 68: 588–594. doi: 10.1002/mrm.23250
- Issue published online: 12 JUL 2012
- Article first published online: 27 DEC 2011
- Manuscript Accepted: 16 SEP 2011
- Manuscript Revised: 12 SEP 2011
- Manuscript Received: 1 JUL 2011
- NIH-NCRR. Grant Number: P41RR002305
- NIAMS. Grant Numbers: NIH-R01AR45404, NIH-R01AR051041
- saturation pulse;
The sensitivity of chemical exchange saturation transfer (CEST) on glycosaminoglycans (GAGs) in human knee cartilage (gagCEST) in vivo was evaluated at 3 and 7 T field strengths. Calculated gagCEST values without accounting for B0 inhomogeneity (∼0.6 ppm) were >20%. After B0 inhomogeneity correction, calculated gagCEST values were negligible at 3 T and ∼6% at 7 T. These results suggest that accurate B0 correction is a prerequisite for observing reliable gagCEST. Results obtained with varying saturation pulse durations and amplitudes as well as the consistency between numerical simulations and our experimental results indicate that the negligible gagCEST observed at 3 T is due to direct saturation effects and fast exchange rate. As GAG loss from cartilage is expected to result in a further reduction in gagCEST, gagCEST method is not expected to be clinically useful at 3 T. At high fields such as 7 T, this method holds promise as a viable clinical technique. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.