Fig. 1.

Graphical model for the proposed segmentation approach. Voxels are indexed with i, channels are indexed by c. The known prior π_k determines the label k of the normal healthy tissue. The latent atlas α determines the channel-specific presence of tumor t. Normal tissue label k, tumor labels t, and intensity distribution parameters θ jointly determine the multimodal image observations y. Observed (known) quantities are shaded. The segmentation algorithms aims to estimate $p\left(t_i^c|\mathit{y}\right)$, along with the segmentation of healthy tissue p(k_i|y).