MRI动态增强扫描对垂体微腺瘤的诊断价值

目的：探讨MRI动态增强扫描在垂体微腺瘤中的应用价值。方法：回顾性分析经手术及病理证实的18例垂体微腺瘤的MRI表现。其中6例先行CT扫描。结果：18例垂体微腺瘤中有12例肿瘤位于垂体的一侧，垂体柄向对侧偏移，病变处鞍底有不程度的向下凹陷。3例肿瘤位于垂体中间。2例肿瘤位于垂体内呈散在沙粒状，1例肿瘤位于垂体之下，即垂体与鞍底之间。MRI平扫时18例患者中12例病变在T1WI上为低信号，在T2WI上为稍高信号；6例病变在T1WI上为等信号，在T2WI上为等信号，局部略有隆起，鞍底有不同程度凹陷；所有病变行MRI动态增强后，肿瘤区信号明显低于正常垂体强化信号，形成显著的差别，随着时间延长。肿瘤也逐渐强化。结论：MRI动态增强扫描是垂体微腺瘤首选的影像学检查方法，操作简单、无创伤、无痛苦。

Valuation of Dynamic Constrast Enhanced MR Imaging for Diagnosis of Pituitary Microadenomas

Objective To explore the MRI characteristic and evaluate the use of dynamic contrast enhanced MRI in evaluation of pituitary microadenomas.Methods Eighteen patients with pituitary microadenomas confirmed by operation and pathology examination were retrospectively reviewed.Among them there were 6 patients had CT examined first.Results The microadenoma lied on the side of pituitary were revealed in 12 patients,while the sella petiole drifted on the other side and there were anisodegree incisure of the sella floor on the lesions.On the other hand,there were 3 patients whose tumor lied intermediate of the sella,2 patients with tumors interspersed in the pituitary and 1 intra the sella.In constrast enhanced MR:low intensity of T 1WI and slightly high intensity of T 2WI were revealed in 12 patients,while iso-light intensity of T 1WI and light intensity of T 2WI were in 6 patients.In dynamic MR grading system:the imagings of the tumor area were deeply lower then the constrast enhanced imaging of common sella,which formed marked difference.Conclusion dynamic constrast enhanced MR is the first selected radiologic examination of pituitary microadenomas,which has the advantages of simple operation without hurt and distress.