IOUS and CE-IOUS during hepatic resection for patients with hepatocellular carcinoma in liver cirrhosis1.

PURPOSE

To retrospectively evaluate the role of intraoperative ultrasonography (IOUS) and contrast-enhanced IOUS (CE-IOUS) for the patients with hepatocellular carcinoma (HCC) undergoing hepatic resection (HR).

METHODS

Twenty-one consecutive patients who had undergone HR for HCC were included in this study. The patients were subject to preoperative imaging modalities including preoperative ultrasonography (Pre-US) and preoperative contrast-enhanced ultrasonography (Pre-CEUS). All the patients then underwent intraoperative ultrasonography (IOUS) and contrast-enhanced intraoperative ultrasonography (CE-IOUS) during surgery. The visualization of primary HCC and additional lesions of all patients were analyzed.

RESULTS

Twenty-one HCCs were detected during Pre-US and the remaining six lesions (28.6%) were detected during IOUS and CE-IOUS. Thus the treatment plan was changed in 28.6% of patients. Twenty-one HCCs (diameter, 0.6-3.0 cm; mean±SD, 1.98±0.85 cm) were measured on Pre-US and remeasured on IOUS (diameter, 0.9-3.3 cm; mean±SD, 2.19±0.84 cm) (p < 0.001). The 6 additional lesions consisted of three moderately differentiated HCCs, one cholangiocarcinoma (ICC), and two high-grade dysplastic nodules (DNs). The mean maximal diameter of the 6 additional lesions was 0.83 cm (range: 0.6-1.1 cm). The malignancy associated features such as capsule interruption, echo heterogeneity, hypo-echoic rim, and a nodule in nodule pattern were more often depicted on IOUS than on Pre-US (all p < 0.01). On CEUS, 19 (90.5%) of 21 HCCs were hyper-enhanced in the arterial phase and washed out from the portal phase to the late phase; the remaining two (9.5%) were hypoenhanced. On CE-IOUS, tumor vasculatures were classified as four patterns: 11 (52.4%) exhibited netlike pattern, 7 (33.3%) annular pattern, 2 (9.5%) mixed pattern, and 1 (4.8%) radial pattern. 3 mHCCs and 2 DNs of six additional nodules had similar greyscale imagining features on IOUS, but they showed different enhancement patterns on CE-IOUS. The ICC showed slightly heterogeneous enhancement during the arterial phase and hypo-enhancement during the portal phase.

CONCLUSIONS

IOUS detects more lesions and the treatment plan is changed in 28.6% of patients. HCCs were larger on IOUS than on Pre-US. The typical imaging features of HCCs were better depicted on IOUS in comparison with Pre-US. CE-IOUS can catch the details of microcirculation perfusion of HCCs more sensitively than CEUS. Both IOUS and CE-IOUS were able to provide more decision information during surgery.