胰岛细胞瘤的影像学表现（附10例分析）

目的胰岛细胞瘤较少见，目前对胰岛细胞瘤的CT表现报道较多，MRI表现报道较少。本研究分析胰岛细胞瘤的CT及MRI表现，着重探讨MRI的诊断价值。方法回顾性分析经手术病理证实的10例胰岛细胞瘤的CT及MRI表现。结果10例胰岛细胞瘤中，8例为功能性胰岛细胞瘤，2例为无功能性胰岛细胞瘤，其中4例为恶性。胰岛素瘤普通CT多表现为等密度，轻度强化，较易漏诊。MRI多表现为T1WI低信号，T2WI高信号，常规增强后轻度强化，动态MRI增强早期可明显强化。功能性胰岛细胞瘤体积多较小，无功能性或恶性胰岛细胞瘤体积多较大。恶性胰岛细胞瘤多伴肝脏或淋巴结转移。结论胰岛细胞瘤的影像学表现具有一定的特征性，MRI较常规CT能提供更多的诊断信息．尤其是动态增强MRI。

Imaging findings of pancreatic islet cell tumor:analysis of 10 cases

Objective To emphasize the value of MRI in the diagnosis of pancreatic islet cell tumor by analyzing CT and MRI features. Methods CT and MRI findings in 10 patients with surgical-pathologically-proved islet cell tumor were retrospectively analyzed. Results of 10 cases, 8 were functional insulinoma and 2 were nonfunctional tumors, including 4 cases malignant islet cell tumor. Most of the islet cell tumor appeared iso-attenuation and slightly enhanced on conventional CT, which was easily ignored. MRI showed hypo-intensity signal on T1-weighted images and hyper-intensity signal on T2-weighted images, with slightly enhancement on conventional contrast images but intensely enhancement on early phase after dynamic contrast enhancement. The size of insulinoma was relatively small, while that of nonfunctional or malignant islet cell tumors were relatively larger. Liver or lymphoid metastases were frequently occurred in malignant islet cell tumors. Conclusion The islet cell tumors reveal some characteristic imaging features. MR imaging, especially dynamic contrast enhancement MR imaging can provide more diagnostic information about the islet cell tumors than conventional CT.