Introduction: The precise intraoperative localization of insulinoma is essential for successful surgical management.
Aims: To assess the usefulness of measuring insulin levels by preoperative percutaneous transhepatic portal catheterization (PTPC) and intraoperative ultrasonography (US).
Methodology: PTPC and other preoperative procedures (enhanced computed tomography [CT], arteriography, and US) were performed in eight patients with insulinoma based on our experience during the past 18 years. Intraoperative US was performed in six of the eight patients.
Results: PTPC was undertaken in all eight patients, and increased levels of insulin at the sites corresponding to tumors were observed in all patients. Intraoperative US was performed in six patients, which made it possible to detect insulinomas as hypoechoic masses in all of these patients. All tumors were found to exist as single entities.
Conclusion: PTPC showed the highest diagnostic accuracy in detecting the number of and accurately localizing the tumors before surgery. Meanwhile, all findings from intraoperative US were identical to those of the resection samples, suggesting that this method is a highly reliable examination technique. We conclude that a combination of PTPC and intraoperative US may be essential for the successful surgical management of insulinomas.