Rethinking Boundary Detection in Deep Learning-Based Medical Image Segmentation

TL;DR

This paper introduces CTO, a novel deep learning architecture combining CNNs, ViT, and edge detection to improve boundary segmentation accuracy in medical images, outperforming existing methods across multiple datasets.

Contribution

The study presents CTO, a new network architecture that integrates local and long-range features with explicit boundary guidance, enhancing boundary segmentation in medical images without extra data or labels.

Findings

Achieves state-of-the-art accuracy on seven medical image datasets.

Balances segmentation accuracy and computational efficiency effectively.

Uses explicit boundary guidance to improve boundary area learning.

Abstract

Medical image segmentation is a pivotal task within the realms of medical image analysis and computer vision. While current methods have shown promise in accurately segmenting major regions of interest, the precise segmentation of boundary areas remains challenging. In this study, we propose a novel network architecture named CTO, which combines Convolutional Neural Networks (CNNs), Vision Transformer (ViT) models, and explicit edge detection operators to tackle this challenge. CTO surpasses existing methods in terms of segmentation accuracy and strikes a better balance between accuracy and efficiency, without the need for additional data inputs or label injections. Specifically, CTO adheres to the canonical encoder-decoder network paradigm, with a dual-stream encoder network comprising a mainstream CNN stream for capturing local features and an auxiliary StitchViT stream for integrating long-range dependencies. Furthermore, to enhance the model's ability to learn boundary areas, we introduce a boundary-guided decoder network that employs binary boundary masks generated by dedicated edge detection operators to provide explicit guidance during the decoding process. We validate the performance of CTO through extensive experiments conducted on seven challenging medical image segmentation datasets, namely ISIC 2016, PH2, ISIC 2018, CoNIC, LiTS17, and BTCV. Our experimental results unequivocally demonstrate that CTO achieves state-of-the-art accuracy on these datasets while maintaining competitive model complexity. The codes have been released at: https://github.com/xiaofang007/CTO.