European Journal of Radiology 31 (1997) 69 – 75 Intracranial meningiomas: correlations between MR imaging and histology Francesco Maiuri a, *, Giorgio I  aconetta a , Oreste de Divitiis b , Sossio Cirillo c , Francesco Di Salle c , Maria Laura De Caro d a Institute of Neurosurgery, School of Medicine, Clinica Neurochirurgica, Facolta ´ di Medina e Chiruriga, Uniersita ` degli Studi ‘Federico II’, Via S. Pansini 5, 80131 Naples, Italy b Institute of Neurosurgery, School of Medicine, Uniersity of Milan, Milan, Italy c Institute of Radiology, School of Medicine, Uniersity of Naples ‘Federico II’, Naples, Italy d Institute of Pathology, School of Medicine, Uniersity of Naples ‘Federico II’, Naples, Italy Received 23 February 1998; received in revised form 22 April 1998; accepted 23 April 1998 Abstract The authors have examined the relationship between magnetic resonance imaging (MRI) and histopathological features in 35 surgically verified intracranial meningiomas. Tumor signals on T1-weighted images were rather similar regardless of the histologic subtype of the tumors. On T2-weighted images, hypointense meningiomas were mainly fibroblastic and hyperintense tumors were mainly syncytial and angioblastic, and partly transitional. Isointense tumors were mainly transitional and partly fibroblastic and syncytial. The authors conclude that the signal intensity of the MRI may be useful in the preoperative characterization of intracranial meningiomas. T1-weighted images may predict the presence of cysts and intratumoral blood vessels; whereas T2-weighted images can give information about histological subtype, vascularity and consistency. Meningiomas hyperintense to the cortex on T2 are usually soft, more vascular and more frequently of syncytial or angioblastic subtype; tumors hypointense or hypo-isointense on T2 tend to have a more hard consistency and are more often of fibroblastic or transitional subtype. © 1999 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Magnetic resonance imaging; Meningiomas; Brain MR; Brain neoplasms www.elsevier.nl/locate/ejrad 1. Introduction The magnetic resonance (MR) appearance of in- tracranial meningiomas has been largely discussed in many reports of the radiological and neurosurgical literature [1 – 6]. Early studies stressed the difficulty in detecting most meningiomas, because of their T1 and T2 signal values similar to those of the normal brain [1,7]. However, later reports have noticed on some pulse sequences a significant number of hyper- or hy- pointense tumors [2,3,8]. Therefore, the accuracy of diagnosis of meningiomas on MR is estimated to be about 95% in most series. The histopathologic features that determine the vari- ability of the signal intensity of meningiomas on MR are not well defined. For this purpose, we have re- viewed the MR and histopathologic features of surgi- cally verified meningiomas to investigate the pathologic bases of the MR signal heterogenicity. 2. Material and methods A total of 35 patients with histologically proven intracranial meningiomas studied by MR and operated * Corresponding author. Tel.: +81 746 2576; fax: +81 746 2594. 0720-048X/99/$ - see front matter © 1999 Elsevier Science Ireland Ltd. All rights reserved. PII: S0720-048X(98)00083-7