Sandell Julia L, Liang Xing, Zhu Timothy
Physics and Astronomy Department, University of Pennsylvania, Philadelphia, PA USA 19104.
Dept. of Radiation Oncology, School of Medicine, University of Pennsylvania, Philadelphia, PA USA 19104.
Proc SPIE Int Soc Opt Eng. 2012 Feb 13;8210. doi: 10.1117/12.908223.
The ability to deliver uniform light dose in Photodynamic therapy (PDT) is critical to treatment efficacy. Current protocol in pleural photodynamic therapy uses 7 isotropic detectors placed at discrete locations within the pleural cavity to monitor light dose throughout treatment. While effort is made to place the detectors uniformly through the cavity, measurements do not provide an overall uniform measurement of delivered dose. A real-time infrared (IR) tracking camera is development to better deliver and monitor a more uniform light distribution during treatment. It has been shown previously that there is good agreement between fluence calculated using IR tracking data and isotropic detector measurements for direct light phantom experiments. This study presents the results of an extensive phantom study which uses variable, patient-like geometries and optical properties (both absorption and scattering). Position data of the treatment is collected from the IR navigation system while concurrently light distribution measurements are made using the aforementioned isotropic detectors. These measurements are compared to fluence calculations made using data from the IR navigation system to verify our light distribution theory is correct and applicable in patient-like settings. The verification of this treatment planning technique is an important step in bringing real-time fluence monitoring into the clinic for more effective treatment.
在光动力疗法（PDT）中实现均匀光剂量输送的能力对治疗效果至关重要。目前胸膜光动力疗法的方案是使用7个各向同性探测器，放置在胸膜腔内的离散位置，以在整个治疗过程中监测光剂量。尽管努力使探测器在腔内均匀放置，但测量结果并不能提供所输送剂量的整体均匀测量。正在开发一种实时红外（IR）跟踪相机，以便在治疗期间更好地输送和监测更均匀的光分布。先前已表明，对于直接光体模实验，使用红外跟踪数据计算的注量与各向同性探测器测量结果之间具有良好的一致性。本研究展示了一项广泛的体模研究结果，该研究使用了可变的、类似患者的几何形状和光学特性（吸收和散射）。从红外导航系统收集治疗的位置数据，同时使用上述各向同性探测器进行光分布测量。将这些测量结果与使用红外导航系统数据进行的注量计算进行比较，以验证我们的光分布理论是正确的且适用于类似患者的情况。验证这种治疗计划技术是将实时注量监测引入临床以实现更有效治疗的重要一步。
