🤖 AI Summary
To address the high computational cost and poor deployability of diffusion models—typically reliant on large U-Net backbones—in resource-constrained medical settings for skin lesion segmentation, this work proposes the first lightweight diffusion-based segmentation framework built upon Neural Cellular Automata (NCA). Methodologically, we introduce a multi-level NCA noise refinement mechanism, an attention-enhanced NCA architecture incorporating CBAM, and an RGB-channel semantic-guided loss, enabling the first synergistic optimization of NCA with Denoising Diffusion Probabilistic Models (DDPM) for medical image segmentation. Experiments demonstrate that our approach achieves a Dice score of 87.84% on skin lesion segmentation—on par with U-Net-based baselines—while reducing model parameters by 60–110×. This substantial parameter reduction significantly enhances feasibility for deployment in low-resource clinical environments.
📝 Abstract
Denoising Diffusion Models (DDMs) are widely used for high-quality image generation and medical image segmentation but often rely on Unet-based architectures, leading to high computational overhead, especially with high-resolution images. This work proposes three NCA-based improvements for diffusion-based medical image segmentation. First, Multi-MedSegDiffNCA uses a multilevel NCA framework to refine rough noise estimates generated by lower level NCA models. Second, CBAM-MedSegDiffNCA incorporates channel and spatial attention for improved segmentation. Third, MultiCBAM-MedSegDiffNCA combines these methods with a new RGB channel loss for semantic guidance. Evaluations on Lesion segmentation show that MultiCBAM-MedSegDiffNCA matches Unet-based model performance with dice score of 87.84% while using 60-110 times fewer parameters, offering a more efficient solution for low resource medical settings.