Application of histogram analysis for the evaluation of vascular permeability in glioma by the K2 parameter obtained with the dynamic susceptibility contrast method: Comparisons with Ktrans obtained with the dynamic contrast enhance method and cerebral blood volume

作者：Taoka Toshiaki^*; Kawai Hisashi; Nakane Toshiki; Hori Saeka; Ochi Tomoko; Miyasaka Toshiteru; Sakamoto Masahiko; Kichikawa Kimihiko; Naganawa Shinji

来源：Magnetic Resonance Imaging, 2016, 34(7): 896-901.

DOI：10.1016/j.mri.2016.04.020

• Permeability imaging
• K2
• Perfusion imaging
• MRI
• Glioma

Purpose: The "K2" value is a factor that represents the vascular permeability of tumors and can be calculated from datasets obtained with the dynamic susceptibility contrast (DSC) method. The purpose of the current study was to correlate K2 with Ktrans, which is a well-established permeability parameter obtained with the dynamic contrast enhance (DCE) method, and determine the usefulness of K2 for glioma grading with histogram analysis.
Methods: The subjects were 22 glioma patients (Grade II: 5, III: 6, IV: 11) who underwent DSC studies, including eight patients in which both DSC and DCE studies were performed on separate days within 10 days. We performed histogram analysis of regions of interest of the tumors and acquired 20th percentile values for leakage-corrected cerebral blood volume (rCBV(20%ile)), K2 (K2(20%ile)), and for patients who underwent a DCE study, Ktrans (Ktrans(20%ile)).We evaluated the correlation between K2(20%ile) and Ktrans(20%ile) and the statistical difference between rCBV(20%ile) and K2(20%ile).
Results: We found a statistically significant correlation between K2(20%ile) and Ktrans(20%ile) (r = 0.717, p < 0.05). rCBV(20%ile) showed a significant difference between Grades II and III and between Grades II and IV, whereas K2(20%ile) showed a statistically significant (p < 0.05) difference between Grades II and IV and between Grades III and IV.
Conclusions: The K2 value calculated from the DSC dataset, which can be obtained with a short acquisition time, showed a correlation with Ktrans obtained with the DCE method and may be useful for glioma grading when analyzed with histogram analysis.