Diffusion-based generative models have been used as powerful priors for
magnetic resonance imaging (MRI) reconstruction. We present a learning method
to optimize sub-sampling patterns for compressed sensing multi-coil MRI that
leverages pre-trained diffusion generative models. Crucially, during training
we use a single-step reconstruction based on the posterior mean estimate given
by the diffusion model and the MRI measurement process. Experiments across
varying anatomies, acceleration factors, and pattern types show that sampling
operators learned with our method lead to competitive, and in the case of 2D
patterns, improved reconstructions compared to baseline patterns. Our method
requires as few as five training images to learn effective sampling patterns.

这篇研究提出了一种利用预先训练的扩散生成模型优化亚采样压缩感知多线圈磁共振成像的采样方式的学习方法，并证明该方法实现的采样运算符可以在不同的解剖结构、加速因子和模式类型的情况下实现具有竞争力，并且在 2D 模式下具有改进的重建效果。