Vector Representations of Vessel Trees
This work addresses the challenge of scalable and topologically consistent modeling of anatomical tree structures in medical imaging, representing an incremental improvement with a novel method for a known bottleneck.
The paper tackles the problem of learning vector representations for 3D vascular networks by introducing a two-stage Transformer-based autoencoder framework, achieving superior reconstruction fidelity and accurate topology preservation on synthetic and coronary artery datasets.
We introduce a novel framework for learning vector representations of tree-structured geometric data focusing on 3D vascular networks. Our approach employs two sequentially trained Transformer-based autoencoders. In the first stage, the Vessel Autoencoder captures continuous geometric details of individual vessel segments by learning embeddings from sampled points along each curve. In the second stage, the Vessel Tree Autoencoder encodes the topology of the vascular network as a single vector representation, leveraging the segment-level embeddings from the first model. A recursive decoding process ensures that the reconstructed topology is a valid tree structure. Compared to 3D convolutional models, this proposed approach substantially lowers GPU memory requirements, facilitating large-scale training. Experimental results on a 2D synthetic tree dataset and a 3D coronary artery dataset demonstrate superior reconstruction fidelity, accurate topology preservation, and realistic interpolations in latent space. Our scalable framework, named VeTTA, offers precise, flexible, and topologically consistent modeling of anatomical tree structures in medical imaging.