Department of Radiology, University of Michigan, Ann Arbor, MI 48109, United States of America.
Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI 48109, United States of America.
Phys Med Biol. 2024 May 14;69(11):115003. doi: 10.1088/1361-6560/ad40f8.
. Digital breast tomosynthesis (DBT) has significantly improved the diagnosis of breast cancer due to its high sensitivity and specificity in detecting breast lesions compared to two-dimensional mammography. However, one of the primary challenges in DBT is the image blur resulting from x-ray source motion, particularly in DBT systems with a source in continuous-motion mode. This motion-induced blur can degrade the spatial resolution of DBT images, potentially affecting the visibility of subtle lesions such as microcalcifications.. We addressed this issue by deriving an analytical in-plane source blur kernel for DBT images based on imaging geometry and proposing a post-processing image deblurring method with a generative diffusion model as an image prior.. We showed that the source blur could be approximated by a shift-invariant kernel over the DBT slice at a given height above the detector, and we validated the accuracy of our blur kernel modeling through simulation. We also demonstrated the ability of the diffusion model to generate realistic DBT images. The proposed deblurring method successfully enhanced spatial resolution when applied to DBT images reconstructed with detector blur and correlated noise modeling.. Our study demonstrated the advantages of modeling the imaging system components such as source motion blur for improving DBT image quality.
. 数字乳腺断层合成术（DBT）由于其在检测乳腺病变方面的高灵敏度和特异性，相比二维乳腺 X 线摄影术显著提高了乳腺癌的诊断水平。然而，DBT 中的一个主要挑战是由于射线源运动导致的图像模糊，特别是在射线源处于连续运动模式的 DBT 系统中。这种运动引起的模糊会降低 DBT 图像的空间分辨率，可能会影响到微钙化等细微病变的可视性。. 我们通过基于成像几何结构推导 DBT 图像的平面内源模糊核，并提出了一种基于生成式扩散模型的图像先验的后处理图像去模糊方法来解决这个问题。. 我们表明，在给定探测器上方高度的 DBT 切片上，源模糊可以用一个平移不变核来近似，并且通过模拟验证了我们的模糊核建模的准确性。我们还展示了扩散模型生成逼真的 DBT 图像的能力。当应用于具有探测器模糊和相关噪声建模的 DBT 图像重建时，所提出的去模糊方法成功地提高了空间分辨率。. 我们的研究表明，对成像系统组件（如源运动模糊）进行建模以提高 DBT 图像质量具有优势。
