PREDICTION OF CONSISTENCY OF MENINGIOMAS WITH PREOPERATIVE MAGNETIC-RESONANCE-IMAGING

BACKGROUND The consistency of a meningioma is one of the important fac tors in determining the surgical outcome. If the surgeon is aware of t he consistency of a meningioma preoperatively, the surgical plans will be influenced. A few papers have described the correlation between co nsistency of meningiomas and their magnetic resonance imaging (MRI) fi ndings. However, prediction of consistency with MRI is still difficult . We have tried to predict the consistency of meningiomas with MRI fin dings more precisely. METHODS AND RESULTS Fifty patients diagnosed as having intracranial meningiomas were studied with 1.5 Tesla MRI. We co mpared the MRI findings with tumor consistency. The intensities of the tumors were categorized into three grades (low, iso, and high) compar ed to that of the gray matter, T-1-weighted images had no specifics, b ut T-2-weighted images and proton density images were useful for the p rediction of tumor consistency. Hyperintensity on protein density (PD) and T-2-weighted images was a sign of a soft tumor. CONCLUSION We pre sume that T-2 and PD are useful for predicting consistency of meningio mas, and their water content is one of the main factors in their consi stency. Histology may be one of the factors helpful in defining the co nsistency of a tumor. In this series, we found no relationship between histology and MRI findings, nor between histology and consistency. If the meningioma is believed to be hard, preoperative endovascular embo lization is beneficial, which will induce necrosis of the meningioma a nd make it soft enough to be removed more easily and safely. (C) 1997 by Elsevier Science Inc.