Department of Radiology, The University of Chicago, IL 60637, USA.
IEEE Trans Med Imaging. 2011 Mar;30(3):606-20. doi: 10.1109/TMI.2010.2089695. Epub 2010 Oct 25.
Micro-computed tomography (micro-CT) is an important tool in biomedical research and preclinical applications that can provide visual inspection of and quantitative information about imaged small animals and biological samples such as vasculature specimens. Currently, micro-CT imaging uses projection data acquired at a large number (300-1000) of views, which can limit system throughput and potentially degrade image quality due to radiation-induced deformation or damage to the small animal or specimen. In this work, we have investigated low-dose micro-CT and its application to specimen imaging from substantially reduced projection data by using a recently developed algorithm, referred to as the adaptive-steepest-descent-projection-onto-convex-sets (ASD-POCS) algorithm, which reconstructs an image through minimizing the image total-variation and enforcing data constraints. To validate and evaluate the performance of the ASD-POCS algorithm, we carried out quantitative evaluation studies in a number of tasks of practical interest in imaging of specimens of real animal organs. The results show that the ASD-POCS algorithm can yield images with quality comparable to that obtained with existing algorithms, while using one-sixth to one quarter of the 361-view data currently used in typical micro-CT specimen imaging.
微计算机断层扫描（micro-CT）是生物医学研究和临床前应用中的重要工具，可提供对成像小动物和生物样本（如血管样本）的直观检查和定量信息。目前，micro-CT 成像使用大量（300-1000）视图采集的投影数据，这可能会限制系统的吞吐量，并由于辐射引起的小动物或样本变形或损坏而潜在地降低图像质量。在这项工作中，我们研究了低剂量 micro-CT 及其在使用最近开发的算法（称为自适应最速下降投影到凸集（ASD-POCS）算法）从大大减少的投影数据中对样本成像的应用，该算法通过最小化图像全变差并强制数据约束来重建图像。为了验证和评估 ASD-POCS 算法的性能，我们在对真实动物器官样本成像的一些实际感兴趣的任务中进行了定量评估研究。结果表明，ASD-POCS 算法可以产生质量可与现有算法相当的图像，同时使用目前典型的 micro-CT 样本成像中使用的 361 视图数据的六分之一到四分之一。
