[Magnetic resonance imaging characteristics and differential diagnosis of common sellar cystic lesions].

Objective: To investigate magnetic resonance imaging (MRI) characteristic and differential diagnostic keypoints of common sellar regional cystic lesions with the purpose of improving differential diagnostic accuracy. Methods: In total, 174 cases of the pathologically diagnosed cystic lesions in sellar region between March 2016 and June 2019 were included in the current retrospective analysis. These cases included Rathke's cleft cyst (n=68), craniopharyngioma (n=48), pituitary adenoma (n=56) and arachnoid cyst (n=2) in the sellar region. The position, texture and morphology of leisions, signal of cystic and solid part, invasion of surrounding tissues and maximum diameter of cysts on the MRI images were evaluated and compared between different groups. SPSS 25.0 software was used for statistical analysis. Results: There were several specific changes on several MRI sequences in Rathke's cleft cysts, craniopharyngioma and pituitary adenoma groups. For Rathke's cleft cysts, round shape, rare polycystic structure, lack of solid part and maximum diameter of cysts which was significantly less than that of craniopharyngioma and pituitary adenoma groups ((17.37±6.12) mm vs (30.29±13.51) mm vs (28.18±11.13) mm, t value was 6.680, 5.838, respectively, all P<0.05), were favorable diagnostic criteria. While, the intracystic nodules were mostly found in craniopharyngioma. There was no high signal intensity in cystic wall on T1WI and T2WI of pituitary adenoma. MRI signal of arachnoid cyst in sellar region was basically the same as CSF signal, with low signal intensity on T1WI and DWI, high signal intensity on T2WI, without enhanced signal. Conclusions: Common sellar regional cystic lesions showed characteristic manifestations on different MRI sequences. Valuable information in the morphology, MRI signal intensity, maximum diameter measurements may improve accuracy of differential diagnosis for sellar regional cystic lesions.目的： 探讨鞍区常见囊性病变的磁共振（MRI）特征性表现及鉴别诊断要点，提高对鞍区囊性病变的鉴别诊断水平。 方法： 回顾性分析2016年3月至2019年6月天津市环湖医院经病理证实的174例鞍区囊性病变患者的MRI影像资料，包括Rathke裂囊肿68例，颅咽管瘤48例，垂体瘤囊变56例，鞍区蛛网膜囊肿2例。比较鞍区囊性病变的生长部位、质地、形状、囊性部分、实性部分、侵袭周围组织情况以及囊肿最大直径等特征。采用SPSS 25.0软件进行统计学分析。 结果： Rathke裂囊肿、颅咽管瘤与垂体瘤囊变MRI特征的分析结果显示，每种疾病在不同序列影像上分别有特异性表现。Rathke裂囊肿形状主要为类圆形，多囊结构较少，质地无实性部分，最大直径明显小于颅咽管瘤及垂体瘤囊变[（17.37±6.12）mm比（30.29±13.51）mm比（28.18±11.13）mm，t值分别为6.680、5.838，P值均<0.05]。囊内结节多见于颅咽管瘤。垂体瘤囊变的囊壁的T1WI与T2WI均无高信号。鞍区蛛网膜囊肿的MRI信号与脑脊液基本相同，T1WI、DWI信号强度低，T2WI信号强度高，无增强信号。 结论： 鞍区常见囊性病变在MRI不同序列影像上分别有特异性表现，其形态学、信号强度、最大直径等指标特点可为鉴别诊断提供有效依据。.