Figure 2.

Comparison of $V_{4\text{DCT}}^{\text{HU}}$ and V_SPECT for (a) patient 16, showing a large separation between the probability density functions of $V_{4\text{DCT}}^{\text{HU}}$ in V_SPECT defect regions and non-defect regions, and (b) patient 18, showing a small separation. Orange outlines in V_SPECT denote defect regions. Both $V_{4\text{DCT}}^{\text{HU}}$ and V_SPECT are shown with a scale from zero to the 90th percentile value.