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arXiv 2605.08030cs.CVcs.LG
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PET-Adapter:全角度和有限角度PET图像重建的测试时间域适应

PET-Adapter: Test-Time Domain Adaptation for Full and Limited-Angle PET Image Reconstruction

Institute of Imaging and Computer Vision, RWTH Aachen University, Germany(成像与计算机视觉研究所,亚琛工业大学,德国);Machine Learning for Medical Data, Heinrich Heine University Düsseldorf, Germany(医学数据机器学习,杜伊斯堡-艾森大学,德国)

Rüveyda Yilmaz, Yuli Wu, Johannes Stegmaier, Volkmar Schulz

AI总结:

PET-Adapter通过测试时间域适应框架,使预训练于phantom数据的生成式PET重建模型适应不同解剖结构、示踪剂和扫描仪配置的临床数据,无需配对真实数据,提升全角度和有限角度重建性能。

摘要:

正电子发射断层扫描(PET)图像重建固有地受到泊松噪声和物理退化因素的挑战,特别是在有限角度采集中更为严重。尽管深度学习方法表现出有前途的性能,但其在未见临床数据分布上的泛化能力仍受限于广泛的重新训练。我们提出PET-Adapter,一种用于生成式PET重建模型的测试时间域适应框架,该模型仅在phantom数据上预训练。我们的方法使模型能够适应具有不同解剖结构、示踪剂和扫描仪配置的临床数据,而无需配对的真实数据。PET-Adapter在适应过程中引入逐层低秩解剖条件化,并采用有序子集期望最大化(OSEM)为基础的预热启动,从物理引导的重建中初始化生成,将扩散步骤从50减少到2而不影响质量。在多个临床数据集上的实验显示,在全角度和有限角度设置中均表现出优越的3D重建性能,突显了所提出方法的临床可行性和计算效率。

英文摘要:

Positron Emission Tomography (PET) image reconstruction is inherently challenged by Poisson noise and physical degradation factors, which are further exacerbated in limited-angle acquisitions. While deep learning methods demonstrate promising performance, their generalization to unseen clinical data distributions remains limited without extensive retraining. We propose PET-Adapter, a test-time domain adaptation framework for generative PET reconstruction models pretrained solely on phantom data. Our method enables adaptation to clinical datasets with varying anatomies, tracers, and scanner configurations without requiring paired ground truth. PET-Adapter introduces layer-wise low-rank anatomical conditioning during adaptation and Ordered Subset Expectation Maximization-based warm-starting that initializes the generation from physics-informed reconstructions, reducing diffusion steps from 50 to 2 without compromising quality. Experiments across multiple clinical datasets demonstrate superior 3D reconstruction performance in both full-angle and limited-angle settings, highlighting the clinical feasibility and computational efficiency of the proposed approach.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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