MRI features of malignant meningioma

MA Hongbing; GAO Feng

Abstract：Objective To explore the MRI characteristics of malignant meningiomas .Methods MRI data of 18 patients with malignant meningiomas proved by pathological results were analyzed .The features including the location , shape, signal intensity, enhancement , necrosis , cystic degeneration , the border , peritumoral brain edema and the change of adjacent dura were observed compared with the pathology .Results In 18 patients,meningiomas was mainly located at the convexity of brain and sagittal sinus in 7 cases (7/18) and 9 cases (9/18) respectively.5 cases (5/18) had regular shape, 13 cases (13/18) had irregular shape. The border was clear in 6 cases (6/18), ill defined in 12 cases (12/18).Homogeneous enhancement was seen in 3 cases (3/18), and heterogeneous enhancement was seen in 13 cases (13/18).13 cases (13/18) had obvious necrosis and cystic degener-ation.13 cases (13/18) had peritumoral brain edema in different degree .12 cases (12/18) showed dural tail sign .9 cases (9/18) invaded adjacent skull.1 case (1/18) had relapse.Conclusion Malignant meningiomas has special features on MRI and correct analysis of the imaging findings and clinical features can be helpful to improve the preoperative diagnosis level .