Fusion of Preinterventional MR Imaging With Liver Perfusion CT After RFA of Hepatocellular Carcinoma: Early Quantitative Prediction of Local Recurrence

Objectives The aim of this study was to evaluate the ability of fusion of pretreatment magnetic resonance (MR) imaging with posttreatment perfusion–CT (P-CT) after radiofrequency ablation (RFA) of hepatocellular carcinomas (HCCs) and to determine treatment success in an objective, quantitative way. Materials and Methods In this institutional review board–approved study, 39 patients (78.4% male; mean age 68.2 ± 8.5 years) with a total of 43 HCCs, who underwent RFA at our institution and had diagnostic pre-RFA MR imaging and post-RFA P-CT, were included in the study. Post-RFA P-CT was performed within 24 hours after RFA. In a first step, the pre-RFA MR imaging, depicting the HCC, was registered onto the post-RFA P-CT using nonrigid image registration. After image registration, the MR data were reloaded jointly with the calculated perfusion parameter volumes into the perfusion application for quantitative analysis. A 3-dimensional volume of interest was drawn around the HCC and the ablation zone; both outlines were automatically projected onto all perfusion maps. Resulting perfusion values (normalized peak enhancement [NPE, %]; arterial liver perfusion [ALP, in mL/min/100 mL]; BF [blood flow, mL/100 mL/min]; and blood volume [BV, mL/100 mL]) and histogram data were recorded. Local tumor recurrence was defined in follow-up imaging according to the EASL guidelines. Results Image registration of MR imaging and CT data was successful in 37 patients (94.9%). Lo...
Source: Investigative Radiology - Category: Radiology Tags: Original Articles Source Type: research