三叉神经节和Meckel''s腔原发性肿瘤的MRI表现

目的 研究三叉神经节和Meckel’s腔原发肿瘤的MRI表现。方法 对14例经病理证实的三叉神经节和Meckel’s腔原发肿瘤患包括4例三叉神经鞘瘤，5例脑膜瘤，1例脂肪瘤，以及4例表皮样囊肿的MRI表现进行了分析。结果 三叉神经鞘瘤在T1WI上呈均匀低信号，在T2WI上呈高信号。5例脑膜瘤中的3例在T1WI和T2WI上与周围脑组织信号一致，1例在T1WI上呈低信号，在T2WI上呈高信号，另1例在CT图像上有丰富的钙质沉着而在T1WI和T2WI上均呈低信号。脂肪瘤信号均匀且与眶内和皮下脂肪信号一致。4例表皮样囊肿的2例在T1WI和T2WI上呈非常高的信号，另外2例呈匍匐性生长并且占位效应较轻。肿瘤侵犯三叉神经能很好的显示其范围。结论 发生自三叉神经节和Meckel’s腔的不同原发肿瘤具有各自的信号特征，可通过MR成像予以鉴别。

MR imaging of primary tumors of trigeminal nerve ganglion and Meckel''''s cave

Objective To investigate the MRI findings of primary tumors arising from the trigeminal nerve ganglion and Meckel's cave.Methods MRI findings of 14 patients with pathologically proved primary tumors of trigeminal nerve ganglion and Meckel's cave,in whick included 4 trigeminal schwannomas,5 meningiomas,1 lipoma and 4 epidermoid cysts were analyzed.Results The trigeminal schwannomas were homogeneous hypointense on T1WI and hyperintense on T2WI.3 of 5 cases with meningioma had signal intensity similar to that of surrouding brain tissue on T1WI and T2WI.1 case was hypointense on T1WI and hyperintense on T2WI,and other 1 case was relative hypointense on T1WI and T2WI owing to heavy calcinosis demonstrated on CT.The lipoma was homogeneous signal intensity that was isointense with intraorbital and subcutaneous fat on both T1WI and T2WI.The epidermoid cysts were hypointense on T1WI and obvious hyperintense on T2WI,in addition,the individual cyst also presented a repent growth pattern and minimal mass effect.The extent of involvement in the trigeminal nerve distribution was well demonstrated in each case.Conclusion Different primary tumors arising from trigeminal nerve ganglion and Meckel's cave have each signal features that can be differentiated by MR imaging.