Objective To evaluate the clinical value of selective intra-arterial calcium stimulated venous sampling ( ASVS) for the localization of pancreatic insulinoma preoperatively.Methods The clinical data of 28 insulinoma patients admitted from May 2000 to June 2010 in Ruijin Hospital undergoing selective intra-arterial calcium stimulated venous sampling with diagnosis of insulinomas before surgery were analyzed retrospectively.Results There were 12 males and 16 females.All the patients had Whipple's triad, and with proved insulinomas by postoperative pathology.There were 26 cases of single insulinoma and 2 cases of multiple insulinomas with altogether 32 insulinomas resected.78.1% of insulinomas were less than 20 mm.All patient were examined by selective intra-arterial calcium stimulated venous sampling.The peak ratio of insulin to the baseline after calcium stimulation appeared at the superior mensenteric artery (SMA) in 6 cases, and the peak ratio of insulin to the baseline after calcium stimulation appeared at gastroduodenal artery(GDA), proximal splenic artery (SAP) and distal splenic artery (SAD) in 9 cases, 6 cases and 6 cases respectively; Selective intra-arterial calcium stimulated venous sampling accurately located 25 cases, and selective intra-arterial calcium stimulated venous sampling located 2 cases wrongly.In one patient, the selective intra-arterial calcium stimulated venous sampling was falsely negative.The mean and median peak ratio of insulin to the baseline after calcium stimulation were 8.8 folds and 14.8 folds respectively.Accurate rate of selective intra-arterial calcium stimulated venous sampling was 89.3% (25/28) and it was higher than that of computed tomography (CT) (56.5% ) , magnetic resonance imaging (MRI) (60.0%).Sensitivity of selective intra-arterial calcium stimulated venous sampling was 96.2%, which was higher than that of computed tomography ( 69.6% ) , magnetic resonance imaging (75.0% ).Conclusion Selective intra-arterial calcium stimulated venous sampling is superior to computed tomography, or magnetic resonance imaging as a preoperative localizing tool for insulinomas, since this procedure is invasive it should be used when other preoperative morphologic studies (computed tomography or magnetic resonance imaging) failed.

Objective To summarize the diagnosis and surgical therapeutic experience of insulinoma.Methods The clinical data of 130 patients with insulinoma confirmed by pathologic examination from 1966 to 2008 were analyzed retrospectively.Results All the patients had Whipple's triad.37.7％ were once misdiagnosed.Only 43.8 ％ were diagnosed correctly within one year after the onset of symptoms.The average time of evolution was 5.2 years.Ultrasonography,CT,MRI and ASVS were able to localize tumor in 32.9％,70.6％,70.3％ and 88.9％ of the cases,respectively.There were 121 cases (93.1％) of single insulinoma,4 cases (3.1％)of multiple insulinomas,and 5 cases(3.8％)of hyperplasia.127cases(97.7 ％)were benign and 3 cases (2.3 ％)were malignant insulinoma.All the 130 cases underwent surgery,among whom 89 cases were cured by enucleation of tumor.The principal postoperative complications were pancreatic fistula(19.2％) and pancreatitis(3.9％).Conclusions Whipple's triad was with great significance to diagnose insulinoma.Multislice spiral CT is the first choice for preoperative localization of insulinoma and ASVS is an important complementary measure for localizing insulinomas not detected by CT or MRI.Simple enucleation is the most common surgical method.