Image-guided treatment planning for pleural Photodynamic Therapy

描述（由申请人提供）：胸膜光动力学治疗的图像引导治疗计划摘要本基金的总体目标是开发一个集成系统，用于腔内光动力学治疗过程中的实时PDT剂量测定和光源监测。我们建议开发一种基于红外摄像机的系统，用于实时跟踪用于治疗的光源的运动。将使用相同的跟踪系统来测量被处理的腔的表面轮廓，以用于光通量率计算。将使用基于光纤的光谱探头与IR摄像机跟踪装置结合，以确定PDT前后胸膜腔表面多个点的吸收光谱。吸收光谱的分析将确定这些点处的组织氧合和致敏剂浓度。相同的探针将能够执行荧光光谱法，以验证PDT前后的体内药物浓度。吸收光谱还将用于确定体内组织光学特性，并将这些点用作光通量率计算的输入。为了提高异质组织光学特性的空间分辨率，我们计划开发一种光谱反射成像系统，以确定光动力治疗前后组织中光学特性的表面分布。将在7个选定的点处在体内测量光通量率、吸收光谱和荧光发射的时间变化，并与使用光通量计算算法的计算结果进行比较，该算法考虑了腔体的几何形状和光学特性。PDT剂量将计算为药物浓度和光通量率的乘积。我们假设使用PDT剂量作为PDT剂量测定量来优化光源移动将导致PDT治疗的空间均匀性的改善，从而提高其疗效。进一步改善PDT剂量的一个新的剂量测定量，反应单线态氧浓度，考虑到光通量率的影响，将在临床前模型中进行检查。

DESCRIPTION (provided by applicant): Image-guided treatment planning for pleural Photodynamic Therapy Abstract The overall objective of this grant is to develop an integrated system for real-time PDT dosimetry and light source monitoring during intracavitary photodynamic therapy. We propose to develop an infra- red camera-based system for real-time tracking of the motion of the light source used for treatment. The same tracking system will be used to digitize the surface contour of the cavity being treated for light fluence rate calculation. An optical fiber-based spectroscopic probe, coupled with the IR camera tracking device, will be used to determine absorption spectra at multiple points on the pleural cavity surface before and after PDT. Analysis of the absorption spectrum will determine the tissue oxygenation and the sensitizer concentration at these points. The same probe will be capable of performing fluorescence spectroscopy to verify drug concentration in-vivo before and after PDT. The absorption spectrum will also be used to determine the tissue optical properties in-vivo and use these points as input for light fluence rate calculation. To improve the spatial resolution of the heterogeneous tissue optical properties, we plan to develop a spectral reflectance imaging system to determine the surface distribution of optical properties in tissue before and after PDT. The temporal variations of light fluence rate, absorption spectrum, and fluorescence emission will be measured in- vivo at 7 selected points and compared with calculations using a light fluence calculation algorithm which takes into account the geometry and optical properties of the cavity. PDT dose will be calculated as a product of drug concentration and light fluence rate. We hypothesize that using PDT dose as a PDT dosimetry quantity to optimize light source movement will result in improvement of the spatial uniformity of PDT treatment and thus its efficacy. Further improvement of the PDT dose by a new dosimetric quantity, reacted singlet oxygen concentration that takes into account of light fluence rate effect, will be examined in a preclinical model.