Ergys Subashi1,
2, Everett J. Moding3, James R. MacFall4, 5,
David G. Kirsch3, Yi Qi, 25, G. Allan Johnson2,
5
1Medical
Physics Graduate Program, Duke University Medical Center, Durham, NC, United
States; 2Center for In-Vivo Microscopy, Duke University Medical
Center, Durham, NC, United States; 3Department of Pharmacology and
Cancer Biology, Duke University Medical Center, Durham, NC, United States; 4Department
of Biomedical Engineering, Duke University Medical Center, Durham, NC, United
States; 5Department of Radiology, Duke University Medical Center,
Durham, NC, United States
The histogram or mean value of the pharmacokinetic parameters derived from dynamic contrast-enhanced MRI is usually obtained from a manual ROI or from the entire tumor volume. These metrics include tumor regions in which the interpretation of the kinetic parameters is unclear (such as in necrotic areas). In five separate tumor cell lines, we have found that the histogram of the time-to-peak (TTP) parameter can be used to identify tumor sub-volumes with similar enhancement properties. Preliminary results show that the magnitude of response to therapy may be heterogeneous across these sub-regions.