鞍内鞍上型垂体腺瘤、颅咽管瘤、Rathke囊肿的影像学分析

Iconographic analysis for pituitary adenoma, craniopharyngioma and Rathke cleft cyst involving both intrasellar and suprasellar regions

目的 探讨对同时累及鞍内、鞍上的垂体腺瘤、颅咽管瘤和Rathke囊肿三者的影像学差异.方法 对象为2008年1月至2012年1月北京市天坛医院经病理证实的同时累及鞍内、鞍上的垂体腺瘤、颅咽管瘤和Rathke囊肿共99例患者.其中垂体腺瘤40例、颅咽管瘤35例、Rathke囊肿24例.评估以下影像学特征：（1）CT上有无钙化及肿瘤密度;（2）MRI上肿瘤形状、大小（以肿瘤最大直径为标准）、边界范围、构成特征、T2像实性部分的信号强度、T1像囊性部分的信号强度、肿瘤实性部分和囊壁增强的特征及有无伴发脑积水等.利用χ2检验对比3者的差异,构筑一个具有实用价值的影像学鉴别诊断流程图.结果 垂体腺瘤多实性,呈＂雪人征＂,实性部分均质增强.颅咽管瘤多呈分叶状囊实性特征,挤压三室底、实性部分网状增强、CT上钙化多见并伴发脑积水.Rathke囊肿多呈卵圆形囊性特征,体积小、囊壁薄且无增强.结论 上述影像学特征有助于对同时累及鞍内、鞍上的垂体腺瘤、颅咽管瘤和Rathke囊肿的诊断.

Objective To explore the iconographic differences for pituitary adenoma, craniopharyngioma and Rathke cleft cyst involving both intrasellar and suprasellar regions. Methods A total of 99 eligible pathologically confirmed patients （ pituitary adenoma, n = 49 ; craniopharyngioma, n = 35; Rathke cleft cyst, n = 24 ） were selected during January 2008 and January 2012. The following characteristics were evaluated ： （ 1 ） calcification or not and density of tumor on computed tomography （CT） ; （2） shape, size, extent and component characteristics, signal intensities of solid portions on T2-weighted images, signal intensities of cystic portions on T~ -weighted images and enhancement patterns of solid portions and cyst walls and complicated hydrocephaly or not. A flowchart for differential diagnosis for three tumors was constructed based on statistical analysis of the results. Results A snowman shape, solid characteristics and homogeneous enhancement of solid portion were more common in pituitary adenomas ; a lobulated shape, third ventricle compression by superior tumor extension, mixed solid and cystic characteristics, reticular enhancement of solid portion, calcification on CT scan and complicated hydrocephalus were more common in craniopharyngioma; an ovoid shape, small tumor size, cystic characteristics and none or thin cyst wall enhancement were more common in Rathke cleft cysts. Conclusion The above iconography characteristics are helpful in the differential diagnosis of three tumors involving both intrasellar and suprasellar regions.