利用激光散斑成像监测光动力治疗的血管损伤效应

Application of Laser Speckle Imaging: Monitoring Changes of Vessels in Photodynamic Therapy

激光散斑衬比成像(LSCI)技术作为一种高时空分辨的血流流速分布监测技术,无需扫描即可实时地全场记录微循环血流的时空变化特性。鸡胚尿囊膜(CAM)是用于在体研究光动力治疗(PDT)血管损伤效应的理想动物模型。以发育10天鸡胚尿囊膜为模型,使用光敏剂焦脱镁叶绿酸(pyropheophorbideacid,pyroacid),激光照射波长为656.5nm,光照射功率为40mW/cm2,研究了肿瘤周围血管在激光照射下的血管管径变化和血流速度分布变化。研究表明,通过对血管管径和血流速度的监测,激光散斑衬比成像技术可以用于评估光动力治疗过程中的肿瘤周围血管损伤效应。

Laser speckle contrast imaging (LSCI) technique is a new modality to monitoring blood flow dynamics with high spatio-temporal resolution. It records the full-field spatio-temporal characteristics of microcirculation without the need of scanning in real time. In this study, an in vivo model of chick chorioallantoic membrane (CAM) at embryo age (EA) of 10 days, was observed following photodynamic therapy (PDT) irradiated by semiconductor laser (λ=656.5 nm) whose light intensity incident on the treatment site was maintained 40 mW/cm2 using the photosensitizer of pyropheophorbide acid (Pyro-acid). The changes of vessel structure and blood flow velocity were recorded respectively. This study shows that LSCI can assess the efficacy of peripheral vessel damage of tumor in PDT by monitoring changes of vessels structure and blood flow velocity.