Zhu Timothy C, Hahn Stephen M, Kapatkin Amy S, Dimofte Andreea, Rodriguez Carmen E, Vulcan Teodor G, Glatstein Eli, Hsi R Alex
Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA, USA.
Photochem Photobiol. 2003 Jan;77(1):81-8. doi: 10.1562/0031-8655(2003)077<0081:ivopon>2.0.co;2.
The optical properties (absorption [mu(a)], transport scattering [mu('s)] and effective attenuation [mu(eff)] coefficients) of normal canine prostate were measured in vivo using interstitial isotropic detectors. Measurements were made at 732 nm before, during and after motexafin lutetium (MLu)-mediated photodynamic therapy (PDT). They were derived by applying the diffusion theory to the in vivo peak fluence rates measured at several distances (3, 6, 9, 12 and 15 mm) from the central axis of a 2.5 cm cylindrical diffusing fiber (CDF). Mu(a) and mu('s) varied between 0.03-0.58 and 1.0-20 cm(-1), respectively. Mu(a) was proportional to the concentration of MLu.Mu(eff) varied between 0.33 and 4.9 cm(-1) (mean 1.3 +/- 1.1 cm(-1)), corresponding to an optical penetration depth (8 = 1/(mu(eff)) of 0.5-3 cm (mean 1.3 +/- 0.8 cm). The mean light fluence rate at 0.5 cm from the CDF was 126 +/- 48 mW/cm2 (N = 22) when the total power from the fiber was 375 mW (150 mW/cm). This study showed significant inter- and intraprostatic differences in the optical properties, suggesting that a real-time dosimetry measurement and feedback system for monitoring light fluences during treatment should be advocated for future PDT studies. However, no significant changes were observed before, during and after PDT within a single treatment site.
使用组织间各向同性探测器在体内测量了正常犬前列腺的光学特性（吸收系数[μ(a)]、输运散射系数[μ('s)]和有效衰减系数[μ(eff)]）。在莫替沙芬镥（MLu）介导的光动力疗法（PDT）之前、期间和之后，于732 nm波长进行了测量。这些系数是通过将扩散理论应用于在距2.5 cm圆柱形扩散光纤（CDF）中心轴几个距离（3、6、9、12和15 mm）处测量的体内峰值注量率而得出的。μ(a)和μ('s)分别在0.03 - 0.58和1.0 - 20 cm⁻¹之间变化。μ(a)与MLu的浓度成正比。μ(eff)在0.33至4.9 cm⁻¹之间变化（平均为1.3 ± 1.1 cm⁻¹），对应的光穿透深度（δ = 1/μ(eff)）为0.5 - 3 cm（平均为1.3 ± 0.8 cm）。当光纤的总功率为375 mW（150 mW/cm）时，距CDF 0.5 cm处的平均光注量率为126 ± 48 mW/cm²（N = 22）。本研究表明前列腺内部和之间的光学特性存在显著差异，这表明在未来的PDT研究中应提倡用于监测治疗期间光注量的实时剂量测量和反馈系统。然而，在单个治疗部位的PDT之前、期间和之后未观察到显著变化。
