Young et al examine the role of dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) perfusion in differentiating pseudoprogression from progression in 20 consecutive patients with treated glioblastoma. MRI perfusion was performed, and relative cerebral blood volume (rCBV), relative peak height (rPH), and percent signal recovery (PSR) were measured. Pseudoprogression demonstrated lower median rCBV (P=.009) and rPH (P<.001), and higher PSR (P=.039) than progression. DSC MRI perfusion successfully identified pseudoprogression in patients who did not require a change in treatment despite radiographic worsening following chemoradiotherapy
((Young RJ, Gupta A, Shah AD, Graber JJ, Chan TA, Zhang Z, Shi W, Beal K, Omuro 
AM. MRI perfusion in determining pseudoprogression in patients with glioblastoma.
Clin Imaging. 2013 Jan-Feb;37(1):41-9. doi: 10.1016/j.clinimag.2012.02.016. Epub 
2012 Jun 8. PubMed PMID: 23151413; PubMed Central PMCID: PMC4755513.))