arXiv:2410.18625physics.med-pheess.IV2024-10

首次实现混合能谱CT图像重建,同步恢复光谱与图像质量。

First performance of hybrid spectra CT reconstruction: a general Spectrum-Model-Aided Reconstruction Technique (SMART)

  • 融合EID与PCD成像原理,建模散射效应提升重建精度。
  • 通过交替优化实现光谱估计与图像重建协同提升。
  • 适用于混合及单一探测器系统,首次在自研设备上验证成功。

混合能谱CT将能量积分探测器(EID)与光子计数探测器(PCD)集成于同一系统,结合了EID大视场优势与PCD高能量、空间分辨率特性,成为能谱CT新方向。然而,两者成像原理不同且几何路径不一致,导致混合数据难以重建。此外,光谱重建质量受光谱估计精度与散射光影响。本文提出一种通用混合能谱重建方法,同时考虑两种探测器的成像机制及前向过程中的散射影响,并引入体素分数约束。采用ADMM交替优化光谱估计与图像重建,使二者相互增强,提升光谱估计准确性和图像质量。该方法首次实现对混合探测器数据的联合光谱与图像重建,可同时处理含散射的混合能谱数据。方法亦适用于单一类型探测器的能谱成像。通过数值实验验证有效性,并在自研混合能谱CT系统上成功完成首次混合能谱重建实验。

原文摘要 · Abstract (English)

Hybrid spectral CT integrates energy integrating detectors (EID) and photon counting detectors (PCD) into a single system, combining the large field-of-view advantage of EID with the high energy and spatial resolution of PCD. This represents a new research direction in spectral CT imaging. However, the different imaging principles and inconsistent geometric paths of the two detectors make it difficult to reconstruct images using data from hybrid detectors. In addition, the quality reconstructed images considering spectrum is affected by the accuracy of spectral estimation and the scattered photons. In this work, Firstly, we propose a general hybrid spectral reconstruction method that takes into account both the spectral CT imaging principles of the two different detectors and the influence of scattered photons in the forward process modelling. Furthermore, we also apply volume fraction constraints to the results reconstructed from the two detector data. By alternately solving the spectral estimation and the spectral image reconstruction by the ADMM method, the estimated spectra and the reconstructed images reinforce each other, thus improving the accuracy of the spectral estimation and the quality of the reconstructed images. The proposed method is the first to achieve hybrid spectral CT reconstruction for both detectors, allowing simultaneous recovery of spectrum and image reconstruction from hybrid spectral data containing scattering. In addition, the method is also applicable to spectral CT imaging using a single type of detector. We validated the effectiveness of the proposed method through numerical experiments and successfully performed the first hybrid spectral CT reconstruction experiment on our self-developed hybrid spectral CT system.

能谱成像图像重建混合探测器

Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。