MRI在鉴别鞍旁海绵状血管瘤与脑膜瘤的表现特点研究

Study on the MRI manifestation characteristics in the differential diagnosis of parasellar cavernous hemangioma and meningioma

目的探讨脑膜瘤和鞍旁海绵状血管瘤应用MRI检查的表现特征。方法选取本院就诊的鞍旁肿瘤22例,均经病理检查和手术证实,回顾性分析鞍旁海绵状血管瘤和脑膜瘤的MRI影像学特征。结果MRI平扫瘤体呈葫芦状或哑铃状,完整包膜,清晰边界,鞍旁病变显著超过鞍内病变,海绵状血管瘤MRI平扫信号均匀,T1WI病灶与脑灰质信号相似,T2WI信号为均匀显著高信号,与脑脊液相似,视交叉及垂体受压显著推移,增强扫描后病变显著强化及延迟强化。脑膜瘤T2WI信号为稍高信号或等信号,与脑实质信号相似,肿瘤信号内部出现T2稍低信号影,稍不均匀,T1WI病灶与脑灰质信号相似。结论脑膜瘤和鞍旁海绵状血管瘤予以MRI平扫及增强扫描可清晰显示其内部结构特征、不同信号强化特征,对二者的鉴别诊断具有重要的临床价值。

Objective To study the MRI(magnetic resonance imaging)manifestation characteristics in the differential diagnosis of parasellar cavernous hemangioma and meningioma.Methods 22 parasellar tumor patients treated from May 2016 to March 2017 in our hospital were selected.Through the pathological examination and surgical confirmation,the MRI manifestation characteristics were retrospectively analyzed.Results The MRI plain scan indicated the calabash-like or dumbbell-shaped tumor with complete capsule and clear boundary;the incidence rate of parasellar lesions was significantly higher than sellar lesions.Based on the MRI plain scan,the cavernous hemangioma had the uniform signals and high T2WI signals just like those in the cerebrospinal fluid.During the process,there were irregular shapes at T2,dotted low signal shadow,and changed optic chiasma and pituitary gland pressing.The signals were enhanced or delayed after the enhancement scan.The T1WI signals were similar with those of grey matter.The meningioma cases presented the slightly higher or equivalent T2WI signals,which were similar with brain parenchyma signals.The brain tumor presented the uneven and slightly low signal shadow at T2.The T1WI signals were similar with those of grey matter.Among 10 parasellar cavernous hemangioma cases,all of them had pituitary fossa,among 12 meningioma cases,10 cases had pituitary fossa.12 meningioma cases had the linear enhanced signals near the meninges,9 enveloped cases and 3 pressed cases in the cavernous sinus segment of internal carotid artery.There were no obvious abnormalities in the enveloped segment.During the operation of meningioma,the tumor was closely attached to cerebral dura mater;the gravel-like and solid corpuscles were presented in the section part.During the operation of cavernous hemangioma,the cavernous sinus,cerebral dura matter and tumor were closely attached,which was featured as dark red color or purple color,pulsatory feeling,sufficient blood supply,high tension and soft matter.The tumor was composed of various dilated blood vessels while the wall was made up of fibroblast and endothelial cells in the cavernous manner.The cavity was filled with red blood cells.Conclusion The MRI plain scan and enhancement scan can clearly present its internal structure and signal enhancement characteristics.Thus,this is of great importance to the differential diagnosis of meningioma and parasellar cavernous hemangioma in clinical practice.