Improvement of Intraoperative Frozen Section Diagnosis in Patients with Biliary Strictures by Levovist Injection into the Bile Duct on Color Doppler Ultrasonography

Background This study evaluates the efficiency of color Doppler ultrasonography-guided intraoperative pancreatic biopsy (CDUS-IPB) using Levovist injected into the bile duct in conjunction with stimulated acoustic emission (SAE) in patients with biliary strictures. Methods The study was performed on 12 patients. After completing a conventional intraoperative pancreatic biopsy (c-IPB), each subject underwent CDUS with SAE imaging using Levovist. Upon identification of the biliary stricture, the IPB was taken from the area surrounding the stricture on the same imaging setting. Section diagnosis of the CDUS-IPB specimen was compared to that of the c-IPB specimen and resected tissue. Results Biliary strictures were identified as enhanced areas of color Doppler signal on CDUS. CDUS-IPB provided adequate specimens from the biliary strictures in all cases and corrected false-negative diagnoses by c-IPB in three cases. Section diagnosis by CDUS-IPB corresponded to the permanent section diagnosis. There were no complications. Conclusions CDUS-IPB with Levovist is an accurate diagnostic tool. The method is especially useful for patients with a suspected malignant biliary stricture who show no tumor mass in preoperative images and no evidence of malignancy on cytologic examinations.