Imaging characteristics of insulinoma

Insolinoma is a rare disease,but with an increased incidence in recent years.From March 2003 to October 2010,16 patients with insulinoma had been admitted to the Nanfang Hospital,and the results of imaging investigation were compared with histopathological examination after operation.All cases had typical Whipple's triad,low plasma glucose and high plasma insulin concentrations. Sixteen tumors were found in total.The detection rate of ultrasonography was 44％ (7/16),and the detection rate of enhanced computed tomography (CT)and magnetic resonance imaging (MRI) were 67％ (8/16) and 75％ (6/8) respectively.The detection rate reached 88％ by combination of CT and MRI.Two patients had no abnormal findings in ultrasonography,CT and MRI,while positive results were found in the arterial stimulation procedure with venous sampiing (ASVS) in both patients.CT or MRI is the preferred approach for localization diagnosis of insulinoma. The ASVS achieves a distinct advantage in localization of insulinoma. Key words: Insulinoma;  Diagnosis;  Computed tomography;  Magnetic resonance imaging