Interpretable Framework for Zero-shot 4D Low-dose CT Denoising
摘要
Four-dimensional CT (4D-CT) tracks tumor motion throughout the breathing cycle for radiation therapy planning, but dose reduction per phase introduces spatio-temporal noise compromising tumor delineation. Existing learning-based denoising methods are either clinically impractical (requiring paired data) or lack interpretability (black-box networks). We present Filter2Noise-4D (F2N-4D), a zero-shot interpretable framework employing content-adaptive bilateral filtering that exploits spatio-temporal information from neighboring slices. Self-supervised training uses interpolation of neighboring slices to construct training pairs. With only 1.8k parameters, F2N-4D achieves competitive performance while maintaining transparency.