Photobiology Unit, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, UK.
Phys Med Biol. 2012 Oct 21;57(20):6327-45. doi: 10.1088/0031-9155/57/20/6327. Epub 2012 Sep 19.
The choice of light source is important for the efficacy of photodynamic therapy (PDT) of non-melanoma skin cancer. We simulated the photodynamic dose (PDD) delivered to a tumour during PDT using theoretical radiation transfer simulations performed via our 3D Monte Carlo radiation transfer (MCRT) model for a range of light sources with light doses up to 75 J cm(-2). The PDD delivered following superficial irradiation from (A) non-laser light sources, (B) monochromatic light, (C) alternate beam diameters and (D) re-positioning of the tumour within the tissue was computed. (A) The final PDD deposited to the tumour at a depth of 2 mm by the Paterson light source was 2.75, 2.50 and 1.04 times greater than the Waldmann 1200, Photocure and Aktilite, respectively. (B) Tumour necrosis occurred at a depth of 2.23 mm and increased to 3.81 mm for wavelengths 405 and 630 nm, respectively. (C) Increasing the beam diameter from 10 to 50 mm had very little effect on depth of necrosis. (D) As expected, necrosis depths were reduced when the tumour was re-positioned deeper into the tissue. These MCRT simulations show clearly the importance of choosing the correct light source to ensure optimal light delivery to achieve tumour necrosis.
光源的选择对于非黑色素瘤皮肤癌的光动力疗法（PDT）的疗效非常重要。我们通过我们的三维蒙特卡罗辐射传递（MCRT）模型进行理论辐射传递模拟，模拟了 PDT 期间肿瘤接受的光动力剂量（PDD），模拟了一系列光源的光剂量高达 75 J cm(-2)。计算了（A）非激光光源、（B）单色光、（C）交替光束直径和（D）肿瘤在组织内重新定位时，浅层照射后传递的 PDD。（A）Paterson 光源在 2 毫米深度沉积到肿瘤的最终 PDD 分别比 Waldmann 1200、Photocure 和 Aktilite 高 2.75、2.50 和 1.04 倍。（B）当波长分别为 405nm 和 630nm 时，肿瘤坏死发生在 2.23mm 的深度，并增加到 3.81mm。（C）将光束直径从 10 毫米增加到 50 毫米对坏死深度几乎没有影响。（D）正如预期的那样，当肿瘤重新定位到更深的组织时，坏死深度会降低。这些 MCRT 模拟清楚地表明了选择正确光源的重要性，以确保最佳的光传递以实现肿瘤坏死。
