Purpose: To determine whether there are statistically significant differences in cerebral blood volume (CBV) and cerebral blood flow (CBF) of brain tumors of different histopathologic types including primary and secondary benign and malignant lesions. To determine whether these measurements relate to tumor grade.
Materials and methods: Forty-five patients with brain tumors, age 2 to 79 years, underwent dynamic contrast-enhanced susceptibility- weighted echo-planar perfusion magnetic resonance imaging (MRI) using a 3T MR scanner. The lesions were evaluated by measurements of relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF). The Mann-Whitney U test was used to compare rCBV and rCBF measurements of tumor groups -- 13 low-grade and 13 high-grade neuroepithelial (NE) tumors, five metastases, 10 meningiomas, and four others. Peritumoral rCBV and rCBF measurements of high grade NE tumors and metastases were also compared. The relationship between rCBV and rCBF measurements was evaluated by Spearman rank correlation.
Results: Measurements of rCBV and rCBF were statistically significantly higher (P < 0.05) in high-grade NE tumors than in low-grade NE tumors. The difference was not statistically significant in comparing high-grade NE tumors with metastases and meningiomas. Peritumoral rCBV of high-grade NE tumors was significantly higher than peritumoral rCBV of metastases (P < 0.05). There was a strong correlation between rCBV and rCBF values.
Conclusion: CBV and CBF measurements provided by 3T perfusion MRI can help to predict NE tumor grading preoperatively, and differentiate between primary brain tumors and metastases.