Feasibility of compressed sensing technique for isotropic dynamic contrast-enhanced liver magnetic resonance imaging.

PURPOSE

To investigate whether an isotropic T1-weighted gradient echo (T1-GRE) sequence using a compressed sensing (CS) technique during liver magnetic resonance imaging (MRI) can improve the image quality compared to that using a standard parallel imaging (PI) technique in patients with hepatocellular carcinoma (HCC).

METHODS

Forty-nine patients with single pathologically confirmed HCC were included in the prospective study, who underwent a 3.0 T MRI including the two T1-GRE sequences (CS and PI). Qualitative analysis including the relative contrast (RC) of liver-to-lesion, liver-to-portal vein and liver-to-hepatic vein on pre-contrast and postcontrast (delayed phase) images were calculated. Respiratory motion artifact, gastrointestinal motion artifact and overall image quality were scored by using a 4-point scale.

RESULTS

RC of liver-to-lesion, liver-to-portal vein and liver-to-hepatic vein measured on both pre-contrast and postcontrast phase images were significantly higher for CS than for PI. The scores of overall image quality was comparable between PI and CS (3.98 ± 0.10vs 3.96 ± 0.13, P = 0.083 for pre-contrast; 3.96 ± 0.16 vs 3.93 ± 0.17, P = 0.132 for postcontrast, respectively). The scores of gastrointestinal motion artifact was significantly higher for PI than for CS (3.92 ± 0.21 vs 3.69 ± 0.33 for pre-contrast; 3.86 ± 0.21 vs 3.59 ± 0.30 for postcontrast, P < 0.001 for both). The scores of respiratory motion artifact was significantly higher for PI only in pre-contrast sequence (3.97±0.11 vs 3.89 ± 0.22, P = 0.002 for pre-contrast; 3.95 ± 0.18 vs 3.90 ± 0.22, P = 0.083 for postcontrast, respectively).

CONCLUSIONS

Compared to the standard PI sequence, the CS technique can provide greater contrast in displaying HCCs and hepatic vessels in MRI without compromise of overall image quality.