Fast 3D Liver Segmentation Using a Trained Deep Chan-Vese Model

This paper introduces an approach for 3D organ segmentation that generalizes in multiple ways the Chan-Vese level set method. Chan-Vese is a segmentation method that simultaneously evolves a level set while fitting locally constant intensity models for the interior and exterior regions. First, its simple length-based regularization is replaced with a learned shape model based on a Fully Convolutional Network (FCN). We show how to train the FCN and introduce data augmentation methods to avoid overfitting. Second, two 3D variants of the method are introduced, one based on a 3D U-Net that makes global shape modifications and one based on a 3D FCN that makes local refinements. These two variants are integrated in a full 3D organ segmentation approach that is capable and efficient in dealing with the large size of the 3D volumes with minimal overfitting. Experiments on liver segmentation on a standard benchmark dataset show that the method obtains 3D segmentation results competitive with the state of the art while being very fast and having a small number of trainable parameters.