鲜红斑痣光动力治疗三维辐照度分析

Three Dimensional Illumination Analysis of Photodynamic Therapy Instrument for Port Wine Stains

光动力疗法已经在鲜红斑痣等疾病的治疗中得到广泛应用,由于皮损表面的辐照度高低直接影响治疗效果,其均匀性一直受到研究人员的关注。本文通过三维扫描仪获得皮损的表面三维点云数据,然后通过色差显著性算法实现病灶分割,选取阵列光动力治疗光源在典型姿态下完成病灶曲面的辐照度均匀性分析。结果显示,当阵列发光二极管光源偏转5度时,病灶表面预期辐照度减小4%;两组间距离变化10mm时,预期辐照度变化5%。该方法不仅实现了光动力治疗时曲面皮损的辐照度评估,也可辅助医生调节治疗光源的位姿获得预期的辐照度分布。

Photodynamic therapy has been widely used in the treatment of port wine stains and other clinical diseases. Because the irradiance on the surface of skin lesions directly affects the treatment outcomes, the uniformity of the irradiance has been paid close attention by researchers. In this paper, three-dimensional point cloud data of skin lesion surface obtained by three-dimensional scanner are firstly projected to two-dimensional plane. Then, the lesion area is segmented by color difference saliency algorithm. At last, a typical light source for photodynamic therapy is selected for simulation calculation under different attitudes, and the irradiance analysis on curved lesions is completed. The results show that the irradiance on the surface of skin lesions with large curvature and far away from the light source will be significantly reduced. In addition, the slight deflection of angle and distance change between the light source and lesion will also significantly change the irradiance distribution. The proposed method is not only useful for the irradiance planning on curved skin lesions during treatment, but also for the adjustment of the light source to achieve the expected therapeutic dose.