Rational: Brain tumor malignancy correlates with tumor neovascularity. This neovascularity manifests increased cerebral blood volume (CBV) and increased vessel permeability (VP). These can be assessed by two essentially different dynamic contrast MRI sequences; T2* for CBV and T1 for VP, which require separate acquisitions and bolus injections. We developed a single bolus acquisition method to assess both parameters - DPASS.
Purpose: To compare the VP to the CBV of tumors as assessed by DPASS.
Methods: From March 2015 to June 2017 154 patients underwent 414 DPASS examinations. The effect of size, anatomic location and treatment on relative VP (rVP) and CBV (rCBV) were assessed visually.
Results: It was difficult to assess rCBV but not rVP in gray matter, pial regions, or regions of high susceptibility. rVP had higher spatial resolution. Some discrepancies between rCBV and rVP were due biologic differences as evidenced by change in time or due to treatment. rVP was more sensitive to motion.
Conclusion: DPASS is feasible without sophisticated software or sequences. It extends the clinical range of tumor neovascularity evaluation by simultaneously assessing the complementary rCBV and rVP values.
