MRI in insulinomas: preliminary findings

Area of Science:

• Endocrinology
• Surgical Oncology
• Diagnostic Imaging

Background:

• Insulinoma diagnosis requires accurate preoperative localization for surgical planning.
• Selective arteriography has been the traditional gold standard for localization.
• Computed tomography (CT), ultrasound (US), and magnetic resonance imaging (MRI) are emerging as alternatives.

Purpose of the Study:

• To evaluate the efficacy of various preoperative and intraoperative imaging modalities for insulinoma localization.
• To compare the diagnostic yield of different imaging techniques in a clinical setting.

Main Methods:

• Retrospective analysis of 7 adult patients undergoing surgery for insulinoma between November 1988 and September 1990.
• Evaluation of diagnostic accuracy for arteriography, CT, preoperative US, MRI, and intraoperative US in detecting insulinomas.
• Correlation of imaging findings with surgical and histological results.

Main Results:

• Eight tumors were resected in 6 patients, with 5 patients cured.
• Detection rates: Arteriography (2), CT (6), preoperative US (6), MRI (5), intraoperative US (6).
• Two small insulinomas (0.2 and 0.7 cm) were identified histologically.
• Intraoperative US and surgical exploration identified 6 tumors, suggesting high efficacy.

Conclusions:

• Intraoperative ultrasound and thorough surgical exploration achieve high detection rates for insulinomas.
• The value of preoperative arteriography and CT may be limited given the success of intraoperative US.
• Further research may support the sufficiency of US and MRI for preoperative localization.