采用光子计数测量的高灵敏度锥束XLCT  

High⁃Sensitivity Cone⁃Beam XLCT Using Photon Counting Measurements

作　　者：韩景灏 贾梦宇[1,2] 周仲兴 高峰[1,2] Han Jinghao;Jia Mengyu;Zhou Zhongxing;Gao Feng(School of Precision Instruments and Optoelectronics Engineering,Tianjin University,Tianjin 300072,China;Tianjin Key Laboratory of Biomedical Detection Technology and Instrument,Tianjin 300072,China)

机构地区：[1]天津大学精密仪器与光电子工程学院,天津300072 [2]天津市生物医学检测技术与仪器重点实验室,天津300072

出　　处：《中国激光》2024年第3期13-19,共7页Chinese Journal of Lasers

基　　金：国家自然科学基金(81971656,62175183)。

摘　　要：X射线激发发光断层成像(XLCT)是一种新兴的混合成像技术,该技术可同时获得目标体结构信息和功能信息。然而,窄束XLCT重建图像虽然具有高空间分辨率,但X射线利用率较低,数据采集时间过长;锥束XLCT系统提高了X射线利用率,缩短了数据采集时间,但有限的探测角度导致图像重建质量相对较低。为解决上述问题,提高X射线利用率,高效实现多角度高灵敏数据采集,提出了一种基于光子计数测量的锥束XLCT系统,并通过仿体实验对其性能进行了验证。仿体实验结果表明,6个角度锥束照射模式下重建图像的相似度系数(DICE)可达50%,系统保真度(SF)和重建浓度误差(RCE)达到0.7以上,可实现3 mg·mL^(-1)以上的荧光物质质量浓度差距的重建。Objective X-ray luminescence computed tomography(XLCT)technology uses X-ray excitation to stimulate specific luminescent materials at the nanoscale,termed phosphor nanoparticles(PNPs),to produce near-infrared light.Photodetectors then capture the emitted near-infrared light signals from these excited PNPs.Through suitable algorithms,the distribution of PNPs within biological tissues can be visualized.This method allows for structural and functional insights into biological tissues,showing great potential for advancement.There are two main types of XLCT systems:narrow-beam and cone-beam.The narrow-beam XLCT system exhibits higher spatial resolution,albeit at the cost of lower X-ray utilization efficiency.This inefficiency results in extended imaging times,limiting its potential for clinical use.Conversely,the cone-beam XLCT system improves X-ray efficiency and shortens detection time.However,the quality of the reconstructed images tends to be lower due to detection angle limitations.To overcome these challenges,there is a need for an innovative XLCT system that realizes rapid and highly sensitive data collection while also maximizing the use of X-ray technology.By addressing these issues,the clinical limitations of XLCT can be reduced to pave the way for its further development,thereby unlocking a plethora of possibilities.Methods This study introduces a new cone-beam XLCT system based on photon-counting measurements,complemented by an associated reconstruction method.Through the synergistic collaboration between the field-programmable gate array(FPGA)based sub-sampling unit and upper-level control unit,the system realizes automated multi-channel measurements.This integration shortens data acquisition time,boosts experimental efficiency,and mitigates the risks associated with X-ray exposure.After the completion of system implementation,we conduct experimental validation of the system and methodology.Specifically,a fabricated phantom is subjected to multi-angle projection measurements using the established system,a

关 键 词：医用光学 X射线激发发光断层成像 系统研制 光子计数 仿体实验 

分 类 号：O436[机械工程—光学工程]