Application of non rigid 3D-registration for accurate subtraction of dynamic liver MR imaging technique in tumor blood supply assessment for hepatocellular carcinoma after transarterial chemoembolization

Abstract

Objective To compare the capacity between contrast-enhanced computed tomography (CT) and non rigid 3D-registration for accurate subtraction of dynamic liver magnetic resonance imaging (MRI) in tumor blood supply assessment for hepatocellular carcinoma(HCC) after transarterial chemoembolization(TACE), and to evaluate the clinical value of 3D-registration for accurate subtraction of dynamic liver magnetic resonance imaging(MRI). Methods Twenty-one patients with HCC followed TACE therapy were included in the study. All the patients underwent both contrast-enhanced CT and MRI. MRI examination used non rigid 3D-registration for accurate subtraction of dynamic liver imaging technique. And the assessment statistics of these patients’ blood supply information of all the lesions both in the CT images and the MRI image that dealt with non rigid 3D-registration were collected. Digital subtraction angiography (DSA) assessment before next TACE therapy and volume changes of the nodule were considered as the golden standard to compare the ability of tumor blood supply assessment of the two methods. Results One hundred and twenty-six lipiodol accumulation lesions were analyzed. The diagnostic accuracy was different between CT and DSA (P<0.001) while no difference between MR and DSA (P=0.375) of all the lipiodol accumulation lesion’s blood supply. In the assessment of lesion’s blood supply, the sensitivity, specificity, false positive rate, false negative rate, correct indices, positive likelihood ratio, negative likelihood ratio and coincidence rate of CT/MR were 6.2%/99.1%, 76.0%/69.2%, 23.1%/30.8%, 93.8%/0.9%, 0.02/0.68, 0.27/3.22, 1.22/0.01, 13.5%/96.0%. Conclusion Non rigid 3D-registration for accurate subtraction of dynamic liver magnetic resonance imaging is superior in tumor blood supply assessment for HCC after TACE than CT and has important clinical value. Key words: CT; MRI; Subtraction; DSA; TACE