血管中的血氧饱和度（Oxygen saturation，StO2）作为影响血管靶向光动力疗法（Vascular targeted photodynamic therapy，V-PDT）疗效的关键要素之一，实验测量了活体裸鼠背皮窗模型中血管的漫反射光谱（450-800 nm），并通过拟合漫反射光谱数据定量获得了血管中的StO2。同时，研究了高氧、低氧和常氧等三种不同氧条件下V-PDT中血管的StO2和血管管径的变化情况。结果表明，高氧和常氧条件下的平均StO2和血管收缩较为显著，但低氧组的平均StO2和血管收缩不明显。在相同氧条件和不同光照功率密度条件下，V-PDT前后靶向血管的平均StO2与血管管径的变化之间没有显著相关性，但V-PDT前后平均StO2的变化量与光照功率密度之间呈正相关。

Monitoring oxygen saturation changes during vasculartargeted photodynamic therapy (V-PDT) is crucial for achieving an optimal therapeutic outcome. In this study, the diffuse reflection spectra in the range from 450 to 800 nm were measured to quantitatively determine oxygen saturation (StO2) of blood vessels in dorsal skinfold window chamber. Furthermore, the changes of the average StO2 and vasoconstriction of blood vessels in the region of interest (ROI) after V-PDT was evaluated when the nude mice breathing either hypoxic, normoxic, or hyperoxic air under normobaric conditions, respectively. The average StO2 and vasoconstriction of blood vessels for normoxic and hyperoxic groups after V-PDT was dramatically changed while no significant change was found for those of blood vessels in hypoxic group. No consistent pattern for the changes of StO2 and vasoconstriction during V-PDT treatment can be observed. However, the V-PDT-induced change in StO2 was positively correlated with various irradiances.