3D nonrigid motion correction for quantitative assessment of hepatic lesions in DCE-MRI.

PURPOSE

To provide nonrigid respiratory motion-corrected DCE-MRI images with isotropic resolution of 1.5 mm, full coverage of abdomen, and covering the entire uptake curve with a temporal resolution of 6 seconds, for the quantitative assessment of hepatic lesions.

METHODS

3D DCE-MRI data were acquired at 3 T during free breathing for 5 minutes using a 3D T -weighted golden-angle radial phase-encoding sequence. Nonrigid respiratory motion information was extracted and used in motion-corrected image reconstruction to obtain high-quality DCE-MRI images with temporal resolution of 6 seconds and isotropic resolution of 1.5 mm. An extended Tofts model was fitted to the dynamic data sets, yielding quantitative parametric maps of endothelial permeability using the hepatic artery as input function. The proposed approach was evaluated in 11 patients (52 ± 17 years, 5 men) with and without known hepatic lesions, undergoing DCE-MRI.

RESULTS

Respiratory motion produced artifacts and misalignment between dynamic volumes (lesion average motion amplitude of 3.82 ± 1.11 mm). Motion correction minimized artifacts and improved average contrast-to-noise ratio of hepatic lesions in late phase by 47% (p < .01). Quantitative endothelial permeability maps of motion-corrected data demonstrated enhanced visibility of different pathologies (e.g., metastases, hemangiomas, cysts, necrotic tumor substructure) and showed improved contrast-to-noise ratio by 62% (p < .01) compared with uncorrected data.

CONCLUSION

3D nonrigid motion correction in DCE-MRI improves both visual and quantitative assessment of hepatic lesions by ensuring accurate alignment between 3D DCE images and reducing motion blurring. This approach does not require breath-holds and minimizes scan planning by using a large FOV with isotropic resolution.