title: Prediction of hard meningiomas: quantitative evaluation based on the magnetic resonance signal intensity.
abstract: BACKGROUND
  From a surgical perspective, presurgical prediction of meningioma consistency is beneficial.
  
  
  OBJECTIVE
  To quantitatively analyze the correlation between the magnetic resonance (MR) signal intensity (SI) or apparent diffusion coefficient (ADC) and meningioma consistency and to determine which MR sequence could help predicting hard meningiomas.
  
  
  METHODS
  This study included 43 patients with meningiomas who underwent preoperative MR imaging (MRI), including T1-weighted (T1W) imaging, T2-weighted (T2W) imaging, fluid-attenuated inversion recovery (FLAIR), diffusion-weighted imaging (DWI), contrast-enhanced (CE)-T1W imaging, and CE-fast imaging employing steady-state acquisition (FIESTA). A neurosurgeon evaluated the tumor consistency using a visual analog scale (VAS) with the anchors "soft" (score = 0) and "hard" (score = 10). The SI ratio (tumor to cerebral cortex SI) and ADC value were compared with the tumor consistency. The sensitivity, specificity, and accuracy for predicting hard meningiomas (VAS score ≥8; 9 of 43 patients) were calculated using cutoff values for the SI ratio that were obtained in a receiver operating characteristic curve analysis.
  
  
  RESULTS
  A significant negative correlation was observed between the tumor consistency and the SI ratio on T2W imaging, FLAIR, and CE-FIESTA (P < 0.05) but not on T1W imaging, CE-T1W imaging, and the ADC value. The sensitivity, specificity, and accuracy for predicting hard meningiomas were 89%, 79%, and 81% with T2W imaging; 89%, 76%, and 79% with FLAIR; and 100%, 74%, and 79% with CE-FIESTA, respectively.
  
  
  CONCLUSIONS
  Our results suggest that a quantitative assessment using conventional T2W imaging or FLAIR may be a simple and useful method for predicting hard meningiomas.
authors.affiliation: Department of Radiology, University of Occupational and Environmental Health School of Medicine, Japan sapient@med.uoeh-u.ac.jp.
authors.forename: Keita
authors.initials: K
authors.lastname: Watanabe
authors.affiliation: Department of Radiology, University of Occupational and Environmental Health School of Medicine, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Kakeda
authors.affiliation: Department of Neurosurgery, University of Occupational and Environmental Health School of Medicine, Japan.
authors.forename: Junkoh
authors.initials: J
authors.lastname: Yamamoto
authors.affiliation: Department of Radiology, University of Occupational and Environmental Health School of Medicine, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Ide
authors.affiliation: Department of Radiology, University of Occupational and Environmental Health School of Medicine, Japan.
authors.forename: Norihiro
authors.initials: N
authors.lastname: Ohnari
authors.affiliation: Department of Neurosurgery, University of Occupational and Environmental Health School of Medicine, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Nishizawa
authors.affiliation: Department of Radiology, University of Occupational and Environmental Health School of Medicine, Japan.
authors.forename: Yukunori
authors.initials: Y
authors.lastname: Korogi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging; D008297:Male; D008579:Meningioma / Q000473:pathology* / Q000601:surgery; D008875:Middle Aged; D011300:Preoperative Care / Q000379:methods*; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media
keywords: Meningioma; apparent diffusion coefficient (ADC); consistency; magnetic resonance imaging (MRI); signal intensity