Sonazoid-enhanced intraoperative ultrasonography in patients with biliopancreatic diseases: A preliminary study

Background: Ultrasonography using Sonazoid, a novel contrast agent containing microbubbles is a useful diagnostic modality for intrahepatic mass lesions by specific characteristics in two phases of contrast enhancement of early vascular perfusion and perfusion defect of the lesion in the late phase. To improve diagnostic accuracy of intraoperative ultrasonography (IOUS) in biliopancreatic neoplasms, we investigated the usefulness of Sonazoid contrast agent as a preliminary study. Methods We examined IOUS images in 24 patients with the biliopancreatic diseases. Sonazoid was administered intravenously, and the early arterial- and nenous-phase images of tumor were observed during laparotomy. Results Tumors included the localized type of adenomyomatosis in the fundus of gallbladder (GAM) in seven patients as a benign control, adenomatous diseases of biliopancreatic lesions in four, gallbladder carcinoma (GC) in 12, and papilla adenocarcinoma in one. Scanning by Sonazoid IOUS was accomplished in all patients with no adverse effects. Although GC showed high enhancement in 83% of the tumors, GAM and adenoma also showed enhancement in more than half of them, whereas the VA and an intrahepatic duct adenoma were not enhanced. Pseudo-positivity was observed in one case of hyperplastic polyp, and pseudo-negativity was observed in two patients. Cholesterol polyps and liver metastases were not enhanced by Sonazoid. Conclusion Sonazoid IOUS is an alternative useful diagnostic tool to detect vascularity indicating malignancy or tumor extent that allows adequate surgical resection to be performed.