Two- versus three-dimensional dual gradient-echo MRI of the liver: a technical comparison.

OBJECTIVE

To compare 2D spoiled dual gradient-echo (SPGR-DE) and 3D SPGR-DE with fat and water separation for the assessment of focal and diffuse fatty infiltration of the liver.

METHODS

A total of 227 consecutive patients (141 men; 56 ± 14 years) underwent clinically indicated liver MRI at 1.5 T including multiple-breath-hold 2D SPGR-DE and single-breath-hold 3D SPGR-DE with automatic reconstruction of fat-only images. Two readers assessed the image quality and number of fat-containing liver lesions on 2D and 3D in- and opposed-phase (IP/OP) images. Liver fat content (LFC) was quantified in 138 patients without chronic liver disease from 2D, 3D IP/OP, and 3D fat-only images.

RESULTS

Mean durations of 3D and 2D SPGR-DE acquisitions were 23.7 ± 2.9 and 97.2 ± 9.1 s respectively. The quality of all 2D and 3D images was rated diagnostically. Three-dimensional SPGR-DE revealed significantly more breathing artefacts resulting in lower image quality (P < 0.001); 2D and 3D IP/OP showed a similar detection rate of fat-containing lesions (P = 0.334) and similar LFC estimations (mean: +0.4 %; P = 0.048). LFC estimations based on 3D fat-only images showed significantly higher values (mean: 2.7 % + 3.5 %) than those from 2D and 3D IP/OP images (P < 0.001).

CONCLUSION

Three dimensional SPGR-DE performs as well as 2D SPGR-DE for the assessment of focal and diffuse fatty infiltration of liver parenchyma. The 3D SPGR-DE sequence used was quicker but more susceptible to breathing artefacts. Significantly higher LFC values are derived from 3D fat-only images than from 2D or 3D IP/OP images.