Characterization and correction of the effects of hepatic iron on T relaxation in the liver at 3.0T.

Purpose: Quantitative T imaging is an emerging technique to assess the biochemical properties of tissues. In this paper, we report our observation that liver iron content (LIC) affects T quantification of the liver at 3.0T field strength and develop a method to correct the effect of LIC.

Theory And Methods: On-resonance R (1/T ) is mainly affected by the intrinsic R (1/T ), which is influenced by LIC. As on-resonance R is closely related to the Carr-Purcell-Meiboom-Gill (CPMG) R , and because the calibration between CPMG R and LIC has been reported at 1.5T, a correction method was proposed to correct the R contribution to the R . The correction coefficient was obtained from the calibration results and related transformed factors. To compensate for the difference between CPMG R and R , a scaling factor was determined using the values of CPMG R and R , obtained simultaneously from a single breath-hold from volunteers. The livers of 110 subjects were scanned to validate the correction method.

Results: LIC was significantly correlated with R in the liver. However, when the proposed correction method was applied to R , LIC and the iron-corrected R were not significantly correlated.

Conclusion: LIC can affect T in the liver. We developed an iron-correction method for the quantification of T in the liver at 3.0T.