异位垂体腺瘤的磁共振成像表现

MRI findings of ectopic pituitary adenomas

目的探讨异位垂体腺瘤的MRI表现，提高对罕见异位垂体腺瘤的影像学诊断。方法回顾性分析北京协和医院2000年1月至2014年6月收治的6例经手术及病理诊断为异位垂体腺瘤患者的术前MRI影像及其临床资料。结果6例患者中4例MRI平扫病变表现为等T1、等他信号，1例表现为短T1、长T2信号，1例表现为短T1、等他信号，增强扫描后2例表现为较均匀强化，信号低于垂体组织，1例为不均匀强化，3例强化不明显。4例垂体大小、形态正常，2例合并空泡蝶鞍。肿瘤组织病理均符合垂体腺瘤，其中4例为促肾上腺皮质激素腺瘤，1例为催乳素腺瘤，1例为促甲状腺激素腺瘤。结论当患者出现垂体激素相关的内分泌功能异常，MRI示蝶鞍垂体以外区域有占位性病变，尤其是鞍上、与鞍内垂体分界清晰、增强后信号低于正常垂体组织，同时合并空泡蝶鞍的情况下，要考虑到异位垂体腺瘤的可能。

Objective To investigate the magnetic resonance imaging （MRI） findings of ectopic pituitary adenomas （EPA） and to improve the imaging diagnosis of rare ectopic pituitary adenomas. Methods The preoperative MRI and clinical data of 6 patients with EPA diagnosed by surgery and pathology admitted to Peking Union Medical College Hospital from January 2000 to June 2014 were analyzed retrospectively. Results Of the 6 patients, 4 showed isointense on T1 and T2, 1 showed short T1 and long T2, and 1 showed short T1 and isointense T2. Two patients showed more homogeneous enhancement after the enhanced scan, and the signal was lower than the pituitary tissue, 1 was heterogeneous enhancement, and the enhancement of 3 patients was not obvious. The pituitary size and morphology were normal in 4 cases, and 2 patients were combined with empty sella. The pathology of tumor tissue was consistent with pituitary adenomas, 4 of them were adrenocorticotropic hormone adenomas, 1 was prolactin adenoma, and 1 was thyrotroph adenoma. Conclusions When patients have pituitary hormone-related endocrine abnormality, MRI shows occupying lesions outside the area of sella pituitary, especially on the suprasellar region, clear demarcation with intrasellar pituitary gland, and the enhanced signal lower than the normal pituitary tissue, Under the same combined empty sella, the possibility of EPA should be taken into account.