Dynamic contrast-enhanced perfusion MR imaging measurements of endothelial permeability: differentiation between atypical and typical meningiomas.

BACKGROUND AND PURPOSE The measurement of relative cerebral blood volume (rCBV) and the volume transfer constant (K(trans)) by means of dynamic contrast-enhanced (DCE) perfusion MR imaging (pMRI) can be useful in characterizing brain tumors. The purpose of our study was to evaluate the utility of these measurements in differentiating typical meningiomas and atypical meningiomas. METHODS Fifteen patients with pathologically confirmed typical meningiomas and seven with atypical meningiomas underwent conventional imaging and DCE pMRI before resection. rCBV measurements were calculated by using standard intravascular indicator dilution algorithms. K(trans) was calculated from the same DCE pMRI data by using a new pharmacokinetic modeling (PM) algorithm. Results were compared with pathologic findings. RESULTS Mean rCBV was 8.02 +/- 4.74 in the 15 typical meningiomas and 10.50 +/- 2.1 in the seven atypical meningiomas. K(trans) was 0.0016 seconds(-1) +/- 0.0012 in the typical group and 0.0066 seconds(-1) +/- 0.0026 in the atypical group. The difference in K(trans) was statistically significant (P <.01, Student t test). Other parameters generated with the PM algorithm (plasma volume, volume of the extravascular extracellular space, and flux rate constant) were not significantly different between the two tumor types. CONCLUSION DCE pMRI may have a role in the prospective characterization of meningiomas. Specifically, the measurement of K(trans) is of use in distinguishing atypical meningiomas from typical meningiomas.