重T2加权灰阶反转成像对大垂体腺瘤视路的显示作用

目的 探讨重T2加权灰阶反转成像检查对大垂体腺瘤及其周围结构的显示作用。方法对15例术前有视力障碍的垂体瘤病人行重T2加权灰阶反转成像及常规T1加权成像，前者TR／TE为5800ms／259ms，后者为600ms／20ms；层厚3mm。结果 重T2加权灰阶反转成像可清晰显示肿瘤与终板、前连合及前交通动脉丛的空间关系；其视神经、视交叉和视束的检测率分别为93.3％、100％和86．7％，而在T1加权成像中则分别为66．7％、93．3％和66．7％，前者对视路的检测率显著性高于后者。结论 重T2加权灰阶反转成像可清楚显示垂体大腺瘤与视路的位置关系，有助于垂体瘤经颅手术的术前策略制定。

Effect of heavily T2 weighted reversed MR images on locating the optic pathway in large pituitary adenoma

Objective To explore the effect of heavily T2 weighted reversed(T2R) MR images on showing the relationship of large pituitary adenomas and its surrounding structures.Methods T2R images and conventional T1 weighted images were obtained in 15 patients with pituitary adenomas with visual disturbance.Sequence parameters of TR/TE for T2R images and T1 weighted images were 5800 ms/259 ms and 600 ms/20 ms respectively,with slice thickness of 3 mm.Results Spatial relations of the tumors to the lamina terminalis,anterior commissure and anterior communicating artery complex were clearly shown in T2R images.The optic nerves,optic chiasm and optic tracts were detected in 93.3%,100% and 86.7% of the patients on T2R images and 66.7%,93.3% and 66.7% on T1 weighted images,respectively.Detection rate of optic pathway on T2R images was higher than that on T1 weighted images.Conclusion T2R images can show clearly the position relationship of large pituitary adenoma and the optic pathway,which is useful for the preoperative strategy of transcranial surgery for pituitary adenoma.