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arXiv · 1501.04408

A patient-specific scatter artifacts correction method

Wei Zhao·Stephen Brunner·Kai Niu·Sebastian Schafer·Kevin Royalty·Guang-Hong Chen
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Abstract

This paper provides a fast and patient-specific scatter artifact correction method for cone-beam computed tomography (CBCT) used in image-guided interventional procedures. Due to increased irradiated volume of interest in CBCT imaging, scatter radiation has increased dramatically compared to 2D imaging, leading to a degradation of image quality. In this study, we propose a scatter artifact correction strategy using an analytical convolution-based model whose free parameters are estimated using a rough estimation of scatter profiles from the acquired cone-beam projections. It was evaluated using Monte Carlo simulations with both monochromatic and polychromatic X-ray sources. The results demonstrated that the proposed method significantly reduced the scatter-induced shading artifacts and recovered CT numbers.

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Wei Zhao, Stephen Brunner, Kai Niu, Sebastian Schafer, Kevin Royalty, Guang-Hong Chen. 2015-01-19. A patient-specific scatter artifacts correction method. https://doi.org/10.1117/12.2043923

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