Fig 1.
Two magnetic resonance approaches, MRI and MRSI, acquired in a murine glioblastoma model.
a) Region of interest of the MRI. b) 10-by-10 MRSI grid of voxels, showing the metabolic composition of the tissue at voxel level. c) MRSI grid superimposed on the MRI image. d) MRS example of the non-tumour area of this mouse, indicating the position of a number of relevant metabolites: choline (Cho), creatine (Cr) and N-acetyl aspartate (NAA). e) MRS example of the non-tumour area of this mouse, including lactate/mobile lipids (Lac/ML), and highlighting the changes that occur to these relevant metabolites.
Table 1.
Data used for analysis in this study.
Fig 2.
Delineation of the tumour area used as gold standard in this study.
Images were produced a posteriori by the preclinical bioimaging expert for Groups A (first row), B (second row), and C (third and fourth rows). Two versions, (a) and (b), are available for C179, to study the main tumour mass first, and the two masses later, considering they have different proliferation indices, i.e. the rostral mass (“secondary mass”) had a 5% < PI ≤ 30 while the caudal mass (“core mass”) had a PI > 30%. Additionally, for C819 at day 41, a second (blue) area was highlighted as abnormal.
Fig 3.
Details of the methodology proposed in this study for an extraction of sources in a semi-supervised way, informed by knowledge hauled out from the T2w MRI.
Fig 4.
Results for the cases in Group A, for two classes.
Fig 5.
Results for case C179 for three classes, from Group A.
Fig 6.
Results for the cases in Group B, for two classes.
Fig 7.
Results for the cases in Group C, longitudinal study.
Under each case there is a colour-bar showing the response stage determined by the RECIST criteria throughout the therapy protocol (orange means progressive disease, yellow stable disease and green partial response). At the bottom it is indicated when the three TMZ cycles were administered.
Table 2.
Overall sensitivity/specificity and Dice score of the correct delimitation of the tumour mass.
Table 3.
Overall Euclidean distance / shape similarity score (%) and Hausdorff distance.
Fig 8.
MR spectra of three selected voxels from the non-tumour area.