title: Comparison of ADC values of intracranial hemangiopericytomas and angiomatous and anaplastic meningiomas.
abstract: OBJECTIVE
  This study aimed to determine whether the use of apparent diffusion coefficient (ADC) values can improve the diagnostic efficacy of magnetic resonance imaging (MRI) to differentiate hemangiopericytoma (HPC) from angiomatous and anaplastic meningioma.
  
  
  METHODS
  Preoperative diffusion-weighted imaging (DWI) studies of 38 patients with pathologically proven intracranial HPC (n = 12) and angiomatous (n = 13) or anaplastic meningioma (n = 13) were retrospectively reviewed. ADC values were measured in the tumor parenchyma and peritumoral edema, and used to obtain normalized ADC (NADC) ratios (ADC of tumor/ADC of normal white matter).
  
  
  RESULTS
  Mean ADC values were significantly different between HPC and anaplastic meningioma (1.17 ± 0.30 × 10(-3) mm(2)/s and 0.75 ± 0.11 × 10(-3) mm(2)/s, respectively). Mean NADC ratios were also significantly lower in the malignant cases (0.95 ± 0.13) compared with the benign HPCs (1.53 ± 0.39; P < 0.05). Mean ADC values and NADC ratios did not differ significantly between angiomatous meningioma and HPC (P > 0.05), whereas mean ADC values and NADC ratios were lower for anaplastic meningioma than for either angiomatous meningioma or HPC (P < 0.05). Mean ADC value in peritumoral edema in HPC (1.48 ± 0.11 × 10(-3) mm(2)/s) was lower than in either angiomatous (1.73 ± 0.28 × 10(-3) mm(2)/s) or anaplastic (1.72 ± 0.25 × 10(-3) mm(2)/s) meningioma (P < 0.05), and there was no significant difference between ADC values in anaplastic versus angiomatous meningioma (P > 0.05).
  
  
  CONCLUSIONS
  ADC values in tumor parenchyma and peritumoral edema can provide helpful information that is otherwise not available from conventional MRI to differentiate HPC from angiomatous and anaplastic meningioma.
authors: Department of Radiology, Shanghai Cancer Center, Fudan University, 270, Dongan Road, Shanghai 200032, China.
authors: Li
authors: L
authors: Liu
authors: Department of Radiology, Huashan Hospital, Fudan University, 12 Wulumuqi Road Middle, Shanghai 200040, China.
authors: Bo
authors: B
authors: Yin
authors: Department of Radiology, Huashan Hospital, Fudan University, 12 Wulumuqi Road Middle, Shanghai 200040, China.
authors: Dao-ying
authors: DY
authors: Geng
authors: Department of Radiology, Huashan Hospital, Fudan University, 12 Wulumuqi Road Middle, Shanghai 200040, China.
authors: Yuan
authors: Y
authors: Li
authors: Department of Radiology, Huashan Hospital, Fudan University, 12 Wulumuqi Road Middle, Shanghai 200040, China.
authors: Bi-yun
authors: BY
authors: Zhang
authors: Department of Radiology, Shanghai Cancer Center, Fudan University, 270, Dongan Road, Shanghai 200032, China. Electronic address: ybllfd@163.com.
authors: Wei-jun
authors: WJ
authors: Peng
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D001932:Brain Neoplasms / Q000473:pathology*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006392:Hemangioma, Cavernous / Q000473:pathology*; D006393:Hemangiopericytoma / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008577:Meningeal Neoplasms / Q000473:pathology*; D008579:Meningioma / Q000473:pathology*; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult
keywords: Apparent diffusion coefficient; Hemangiopericytoma; Meningioma