256层螺旋CT双期增强扫描对胰岛素瘤的诊断价值

The diagnostic value of dual phase enhanced scan of 256-slice Spiral CT in insulinoma

目的 应用256层螺旋CT双期增强扫描分析总结胰岛素瘤的CT影像特点,评估双期增强扫描对胰岛素瘤的定位诊断价值。方法 随机选取临床疑诊胰岛素瘤患者30例,行CT扫描,以手术后病理及临床定性诊断为对照标准,分析双期CT增强扫描诊断胰岛素瘤的定位诊断效能,并总结分析胰岛素瘤的CT影像特点。结果 24例经手术病理证实为胰岛素瘤,CT扫描检出22例,6例临床定性诊断除外胰岛素瘤患者CT检查均为阴性。CT对胰岛素瘤术前定位诊断的灵敏度、特异度、诊断符合率分别为：91.67%（22/24）、100%（6/6）、93.33%（28/30）。22例胰岛素瘤均为单发,其中1例为恶性肿瘤,余均为良性;肿瘤位于胰头7例,胰体5例,胰尾10例;肿瘤多较小,边缘光整,最大径为0.60~5.22cm;CT平扫多为等低密度病灶,增强扫描动脉期肿瘤明显强化,静脉期肿瘤强化减退,密度减低。结论 胰岛素瘤CT影像表现具有鲜明的特征,应用256层螺旋CT双期增强扫描对胰岛素瘤术前定位诊断具有重要的应用价值。

Objective By use of dual phase enhanced scan of 256-slice Spiral CT, we analyzed the CT characteristics of insulinoma, so as to assess the value of the modality in the diagnosis of this disorder. Methods 30 patients with clinically suspected insulinoma were randomly selected and underwent CT scanning. Taking the postoperative pathology and clinical diagnosis as control standard, we analyzed the diagnostic efficiency for location of insulinoma by dual phase enhanced CT scanning and then, summarized and evaluated the CT characteristics of insulinoma. Results Of those 24 patients with pathologically confirmed insulinoma, 22 cases were detected by CT scan and, except 6 patients with clinical diagnosis of insulinoma, CT examination was negative. The sensitivity of CT for preoperative location for insulin tumor, the diagnostic specificity, and the diagnostic accordance rate were 91.67% （22/24）, 100% （6/6）, 93.33% （28/30）, respectively. 22 cases of insulinoma were all solitary, including that 1 ease was malignant and the others were benign. The tumors located in the pancreatic head in 7 cases, pancreatic body in 5 cases, 10 cases in tail of pancreas. The tumor was small, smooth edge, with the maximum diameter of 0.60 - 5.22 cm. CT scan showed the low density lesions. At the arterial phase, the tumor was markedly enhanced, whereas, at the venous phase, enhancement of tumor was reduced and the density was decreased. Conclusion CT manifestations of insulinoma have distinctive characteristics. Application of dual phase enhanced 256 slice spiral CT scan before surgery is very valuable to the localization diagnosis of insuli- noma.