CT、MRI在颅骨内板骨性突起下脑膜瘤诊断中的价值

CT and MRI diagnosis in the meningioma under the bony protrusion of the inner table of the skull

目的 探讨CT、MRI对颅骨内板骨性突起下脑膜瘤的诊断价值.方法 回顾性分析10例经临床或手术病理证实的颅骨内板骨性突起下脑膜瘤的CT、MRI资料.本研究患者均为女性,年龄37~81岁,平均57岁,均以头痛、头晕就诊.结果 CT显示颅骨内板骨性突起大小约1.1 cm×0.3 cm^1.8 cm×1.0 cm,宽基底与颅内板相连,表面毛糙,其下脑膜瘤呈不均质高密度影,＂帽样＂与骨性突起顶端相连.MRI上骨性突起表面毛糙,与邻近脑膜分界不清,其下脑膜瘤表面凹陷,宽基底与脑膜相连,大小约1.4 cm×1.3 cm^2.0 cm×1.8 cm,T1WI等或稍低信号,T2WI等或稍高信号,明显均质强化,并见＂脑膜尾＂征.结论 CT、MRI对颅骨内板骨性突起下脑膜瘤具有重要诊断价值;充分认识这种少见脑膜瘤的影像学征象对避免漏诊误诊及临床手术治疗均有重要意义.

Objective To investigate the diagnostic value of CT and MRI for the coexistent meningioma under the bony protrusion of the inner table of the skull.Methods CT and MRI manifestations of 10 patients （all females, aged from 37 years old to 81 years old, mean age 57 years old） with coexistent meningioma under the bony protrusion of the inner table of the skull proved by clinic or pathology were reviewed retrospectively.Results The bony protrusion of the inner table of the skull showed ivory-density with rough surface on CT, connecting with the inner table of the skull with wide base, about 1.1 cm×0.3 cm-1.8 cm×1.0 cm in size.The coexistent meningioma under it showed inhomogeneous high density with unclear edge, connecting with the bony protrusion like a hat.The bony protrusion showed uniformly iso-or slightly higher signal intensity on MRI with rough surface, and no clear boundary with adjacent meninges.The coexistent meningioma under it with surface indentation showed iso-or slight hypointensity signal on T1WI and iso-or slighy hyperintensity signal on T2WI, connecting with dura mater with wide base, about 1.4 cm×1.3 cm-2.0 cm×1.8 cm in size.When enhanced, the meningioma showed obviously homogeneous enhancement with ＇＇dural tail＇＇ sign.Conclusions CT and MRI are the optimal modalities in diagnosing the coexistent meningioma under the bony protrusion of the inner table of the skull.