Intraoperative high-resolution ultrasonography in the localization of occult endocrine pancreatic tumours.

Intraoperative pancraticosonography was employed in six patients to localize suspected endocrine tumours and to study the specific ultrasonic features. The cases included four insulinomas, one case of occult G-cell apudoma and one case of beta-cell microadenomatosis. Endocrine tumours are generally hypoechoeic and well defined with smooth borders. The study confirms that real-time operative high resolution sonography is a reliable technique to assist in the diagnosis of occult endocrine tumours and to guide the surgical approach.