On the relative performance of edge illumination x-ray phase-contrast CT and conventional, attenuation-based CT.
On the relative performance of edge illumination x-ray phase-contrast CT and conventional, attenuation-based CT.
复制标题
边缘照明 X 射线相衬 CT 与传统衰减 CT 的相对性能。
DOI：
10.1002/mp.12179
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发表时间：
2017
期刊：
影响因子：
3.8
通讯作者：
Hagen CK
中科院分区：
文献类型：
--
作者：
Hagen CK
目的本文旨在比较边缘照明（EI）X射线相位衬度计算机断层扫描（PCT）和传统的（基于衰减的）计算机断层摄影（CT），基于它们各自的对比度和噪声传递。从而导致对重建的相位断层图像中的噪声的描述。这与用CT获得的相应衰减断层图像中的噪声进行比较。具体而言，推导出一个公式，允许评估的相对性能的两种模式的基础上，他们的对比度噪声比（CNR），为各种实验parameters.ResultsThe噪声功率谱的相位断层扫描图向较低的空间频率，导致从根本上不同的噪声纹理。EI PCT和CT的相对性能，就其CNR而言，与空间分辨率有关：对于较高的空间分辨率（数十至数百μm），相位断层图像中的CNR通常上级于衰减断层图像中的CNR，但对于较低的空间分辨率（数百μm至mm），则较差。小动物或标本成像。
PurposeThis article is aimed at comparing edge illumination (EI) x‐ray phase contrast computed tomography (PCT) and conventional (attenuation‐based) computed tomography (CT), based on their respective contrast and noise transfer.MethodsThe noise in raw projections obtained with EI PCT is propagated through every step of the data processing, including phase retrieval and tomographic reconstruction, leading to a description of the noise in the reconstructed phase tomograms. This is compared to the noise in corresponding attenuation tomograms obtained with CT. Specifically, a formula is derived that allows evaluating the relative performance of both modalities on the basis of their contrast‐to‐noise ratio (CNR), for a variety of experimental parameters.ResultsThe noise power spectra of phase tomograms are shifted towards lower spatial frequencies, leading to a fundamentally different noise texture. The relative performance of EI PCT and CT, in terms of their CNR, is linked to spatial resolution: the CNR in phase tomograms is generally superior to that in attenuation tomograms for higher spatial resolutions (tens to hundreds ofμm), but inferior for lower spatial resolutions (hundreds ofμm to mm).ConclusionThese results imply that EI PCT could outperform CT in applications for which high spatial resolutions are key, e.g., small animal or specimen imaging.