融合血管内超声、光声和光学相干层析成像的多模态定量成像数值分析方法研究

介入血管成像在心血管疾病的研究和临床评估中起着至关重要的作用。多模态血管内联合成像技术结合多种成像手段的优势，仅需一次导管介入，可获得具有诊断价值的充足信息。本项目拟采用数值分析的方法，对结合了血管内超声（IVUS）、光声（PA）和光学相干层析成像（OCT）的多模态血管内定量成像算法进行深入研究。包括：建立单模态和多模态成像数值仿真模型；根据有限角度稀疏光声信号重建高质量的血管横截面初始声压分布图和光学特性参数分布图；解决由组织非均匀声学特性所致的图像质量下降问题；IVUS-PA双模态成像中，联合重建声速、光吸收能量和光吸收系数分布图的方法；IVPA-OCT双模态成像中，联合重建光学参数和热膨胀系数分布图的方法；融合多模态成像信号得到高质量联合图像的方法。本项目的开展将为促进血管内多模态成像技术的发展，使其早日应用于临床诊断和治疗起到推动作用。

Intravascular imaging techniques play an important role in the research and clinical evaluation of cardiovascular diseases. Multimodality intravascular imaging can simultaneously perform multiple imaging modalities through a single imaging probe to provide comprehensive information with diagnostic value. The aim of this project is to comprehensively explore the numerical methods for multimodal quantitative imaging combining intravascular ultrasound (IVUS), photoacoustic (PA) and optical coherence tomography (OCT). Main work includes: (a) numerical modeling and simulation of single-modal and multimodal imaging to obtain computer-simulated images, (b) reconstruction of high-quality images of the initial acoustic pressure and optical parameters from limited-view sparse photoacoustic signals, (c) solution to the problem of image quality degradation caused by acoustic heterogeneity of the imaged tissue, (d) simultaneous recovery of the speed of sound, optical deposition and optical absorption coefficient for IVUS-PA dual-modal imaging, (e) simultaneous recovery of the optical parameters and thermal expansion coefficient for IVPA-OCT dual-modal imaging, and (f) formation of combined images by fusing raw ultrasonic echoes, photoacoustic signals and OCT signals. This project will prompt the development of intravascular multimodal imaging technologies so that they can be utilized in the clinical diagnosis and interventional treatment of cardiovascular diseases as soon as possible.