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

Abstract

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.