T₁- and T₂*-Dominant Extravasation Correction in DSC-MRI: Part II—Predicting Patient Outcome after a Single Dose of Cediranib in Recurrent Glioblastoma Patients

Abstract

A 'vascular normalization index' (VNI) based on the changes in the magnetic resonance imaging (MRI) parameters K trans and cerebral blood volume (CBV), combined with blood sampling, has been shown to correlate with patient outcome in recurrent glioblastoma after a single dose of antiangiogenic therapy. Here, by applying a novel contrast agent extravasation correction method insensitive to variations in tissue mean transit time, we show that a similar VNI parameter can be derived from a single dynamic susceptibility contrast MR acquisition rather than the three parameters shown previously. Our results show that this new VNI parameter, which combines changes in tumoral CBV and an apparent transfer constant from our leakage correction method, may provide prognostic information in an even simpler manner than prior efforts.

Combining angiogenesis inhibition and radiotherapy: A double-edged sword

“…The VEGFR-TKI cediranib induced vascular normalization already at day 1 of treatment, which endured until day 28, in patients with glioblastoma (Batchelor et al, 2007). The technique to measure the 'vascular normalization index' (VNI) using MRI in recurrent glioblastoma has already been optimized and has been shown to correlate with patient outcome after a single dose of cediranib (Emblem et al, 2011). Besides cediranib, it also has been demonstrated that bevacizumab induced vascular normalization 12 days after treatment in patients with rectal carcinoma (Willett et al, 2004).…”

Impact of Software Modeling on the Accuracy of Perfusion MRI in Glioma

“…17–19 Results from our study support this (table 3). Regarding PLD amount, most groups employ a single dose (0.1 mmol/kg) of GBCA 8,9,14–20,22,25,26,42 particularly at 1.5T, although adequate PLD correction could be achieved with GBCA dose as low as 0.05 mmol/kg at 3T. 19 Second, gradient echo (GE) T2*W DSC represents the most preferred and widely published method for DSC.…”

“…8,9,14–18,20,25–28 We present data from a cohort of 52 glioma patients who underwent DSC-pMRI acquisition at the time of clinical MRI examination. The goals of this study are to 1) determine the equivalency of modeling implementation and rCBV calculation across platforms; and 2) to assess whether rCBV variations, if present, will significantly impact correlations with histologic benchmarks.…”

Evaluation of Microvascular Permeability with Dynamic Contrast-Enhanced MRI for the Differentiation of Primary CNS Lymphoma and Glioblastoma: Radiologic-Pathologic Correlation

“…24 Furthermore, the DSC-PWI leakage-correction model assumes that the contrast agent arrives at the same time in the tumor and unaffected normal brain tissue and that tumor and nontumor tissue have equal MTT. 25,26 However, tumor vasculature is extremely variable and heterogeneous, 27 and elevated tumor MTT may cause overestimation of CBV and underestimation of K 2 . 22,26 Therefore, Bjornerud et al 26 recently described a novel leakagecorrection algorithm for evaluating microvascular permeability on DSC-PWI that is insensitive to MTT.…”