选择性动脉钙刺激静脉采血检测胰岛素定位胰岛素瘤的临床研究

目的 研究选择性动脉钙刺激静脉采血(ASVS)检测胰岛素值定位胰岛素瘤的临床应用价值。方法 对连续10例定性诊断为胰岛素瘤的患者术前行ASVS检查。选择性插管至胃十二指肠动脉、肠系膜上动脉、脾动脉近段及远段，分别快速注入葡萄糖酸钙0．3g激发，于激发前后不同时相经肝静脉采血测胰岛素值。计算不同激发值与基础值之比值，取比值最高者为峰比值，认定峰比值最高的动脉所供应的胰腺区域为肿瘤所在区域。结果 ASVS准确定位率为90％，优于B超(30％)、超声内镜(43％)、CT(70％)、MRI(78％)及选择性血管造影(20％)。本组仅2例患者主诉轻度头晕、胸闷。结论 ASVS在胰岛素瘤的定位中较其他影像学检查有更高的准确性，尤其适合于诊断和定位困难的病例。快速注入小剂量钙剂能安全有效地激发肿瘤细胞分泌胰岛素产生峰值。以胰大动脉为界区分脾动脉近段与远段分别激发有助于胰尾肿瘤的定位。

Selective intra-arterial calcium stimulated venous sampling for the localization of pancreatic insulinomas

Objective To evaluate the value of selective intra arterial calcium stimulated venous sampling (ASVS) for the localization of pancreatic insulinoma. Methods Ten consecutive patients with clinically proved insulinoma were enrolled. Gastroduodenal artery, superior mensenteric artery, proximal and distal splenic artery were selectively cathererized for stimulating by rapid injection of 0.3g calcium gluconate. Blood was sampled through hepatic vein prior to and 30, 60, 90, 120, 150 s after stimulation for detecting insulin level. The peak insulin level after stimulation was divided by baseline level, and the highest one was named as peak ratio. The tumor was considered locating at the domain supplied by the artery of peak ratio. Results Accurate rate of ASVS was 90%, and ASVS was higher than that of B US (30%), EUS (43%), CT (70%), MRI (78%) and SAG (20%). Only 2 patients complained slight dizzy and chest distress. Conclusions ASVS has higher accuracy than conventional image studies by focusing the secreting function of insulinoma. It is suitable for some difficult cases. Injecting low dose calcium rapidly can effectively stimulate insulinoma secreting insulin. To separate the proximal splenic artery from the distal one by arteria pancreatic magna and to inject stimulator respectively is helpful for localizing the tumor in pancreas tail.