MRI动态扫描对垂体微腺瘤的诊断价值

Diagnostic Value of Dynamic Scanning MRI in Pituitary Microadenoma

目的:探讨MRI动态扫描对垂体微腺瘤的诊断价值。材料与方法:垂体微腺瘤患者30例均经PHILIP 1.0 NT型MR机行常规矢状面、冠状面T_1WI和T_2WI检查,而后全部又经动态扫描。结果:本组30例的病灶在平扫中,T_1WI呈低信号、T_2WI呈高信号者25例;T_1WI呈等信号、T_2WI呈高信号者3例;T_1WI和T_2WI均呈等信号者1例及高信号者1例。微腺瘤形态征象有垂体柄偏斜(25例)、垂体中央向上膨隆(2例),鞍底下陷(2例),以及瘤内出血(1例),动态扫描后,病灶不增强而正常腺体增强且边界清楚者29例,仅有1例病灶内出血且边界不清楚。结论:MRI动态扫描对垂体微腺瘤的诊断敏感性显著高于平扫,而且它可完整地观察早期正常垂体的增强表现与垂体微腺瘤的增强延迟表现,因而,它有助于对垂体微腺瘤的准确定位,提高诊断准确率。

Purpose: To investigate the diagnostic value of dynamic scanning MRI in pituitary microadeno-mas. Materials and Methods: Thirty patients with pituitary microadenomas initially underwent conventional Ti weighted and T2 weighted MR imaging in the saggital and coronal planes using a 1. 0 NT MR scanner, and then all patients underwent dynamic scanning MR imaging . Results: With plain scan, hypointensity on T1WI and hyperin-tensity on T2WI were seen in 25 patients (83. 3% ), isointensity on T1WI and hyperintensity on T2WI were seen in 3 patients (10% ), isointensity on both T1WI and T2WIwere seen only in 1 patient (3. 3% ). Following dynamic scan in all patients, non - enhanced microadenomas, enhanced normal gland, and clear border were seen in 29 patients (96. 6% ), however, intratumor hemorrhage and unclear border were seen only in 1 patient (3. 3% ). Other signs of microadenoma include upward convexity of pituitary center, deviation of the infundibulum, and downdip of the sellar floor . Conclusions : The diagnostic sensitivity of dynamic scanning MRI in pituitary microadenoma was significantly higher than that of plain scan , and it can comptely observe the early enhanced manifestation of normal gland and the delayed - enhanced manifestation of microadenonma, therefore it is helpful to detect the accurate location of the lesions and to elevate the accurate rate of the diagnosis.