CT与MRI对成人型环状胰腺诊断的对比分析

目的：探讨成人型环状胰腺的计算机体层成像（computed tomography,CT）及磁共振成像（magnetic resonance imaging,MRI）表现,以提高对该病的认识。方法：回顾性分析我院6例成人型环状胰腺病例,其中3例行CT腹部平扫及增强扫描;另外3例行MRI腹部平扫及增强扫描,1例结合磁共振胰胆管成像（magnetic resonance cholangiopancreatography,MRCP）检查。详细分析每例影像学图像表现,最终诊断由2位高年资医师盲法观察,得出共同结果。结果：CT及MRI能显示环状胰腺直接征象和间接征象,6例均能显示直接征象,即胰头增大,呈环形包绕十二指肠,2例能清楚显示环状部胰管走行。间接征象包括肝内胆管扩张（2例）、胆总管扩张（3例）、胰管扩张（4例）、胰腺炎（1例）、胆囊炎（1例）。结论：CT平扫及增强检查显示成人型环状胰腺图像清晰。     

Pituicytoma with pleomorphism: A case report with cytological findings

Pituicytoma is a rare neoplasm, arising in the posterior pituitary or in the hypophyseal stalk, and its cytological findings have not yet been well-described. We have experienced a case of pituicytoma, which was difficult to diagnose intraoperatively, because of its cellular pleomorphism. A tumor measuring 18 mm in maximum diameter was found at the sella turcica in a Japanese woman in her forties. Both intraoperative crush cytology and histology of the resected tumor showed pleomorphic spindle or round cells, including multinucleated cells. Tumor cells were positive for TTF-1, S-100 protein, and vimentin, partially positive for glial fibrillary acidic protein and epithelial membrane antigen, and negative for synaptophysin, hormones of the anterior pituitary gland, CD34, Olig2, PAX8, and napsin A. Ki-67 labeling index was 2.0%. Tumors included in the differential diagnosis in general are pituitary adenoma, craniopharyngioma, germinoma, and metastatic tumor on the radiological standpoint, and pilocytic astrocytoma and meningioma on the cytological standpoint. However, our case was difficult to differentiate especially from high-grade glioma only by morphology, and immunohistochemistry including TTF-1 was helpful.