Techniques measuring post contrast phase include collecting 3D medical imagery of a subject after injection with a contrast agent. A first set of slices is obtained in which each includes a first anatomical feature selected from a portal vein, aorta, inferior vena cava, liver, spleen or renal cortex. A second set of slices is obtained in which each includes a different second anatomical feature. A first image region is obtained from the first set and a different second image region from the second set. A trained convolutional neural network is configured to input the first image region to a first plurality of convolutional hidden layers and the second image region to a second plurality of convolutional hidden layers and output from both to a fully connected hidden layer that outputs a post contrast phase. Output data is presented based on the post contrast phase.