患者特异性治疗计划对深部组织脓肿腔光动力疗法适应证的影响：回顾性蒙特卡罗模拟研究。

Effects of patient-specific treatment planning on eligibility for photodynamic therapy of deep tissue abscess cavities: retrospective Monte Carlo simulation study.

机构信息

University of Rochester, The Institute of Optics, Rochester, New York, United States.

University of Rochester, Department of Biomedical Engineering, Rochester, New York, United States.

出版信息

J Biomed Opt. 2022 Feb;27(8). doi: 10.1117/1.JBO.27.8.083007.

SIGNIFICANCE

Antimicrobial photodynamic therapy (PDT) effectively kills bacterial strains found in deep tissue abscess cavities. PDT response hinges on multiple factors, including light dose, which depends on patient optical properties.

AIM

Computed tomography images for 60 abscess drainage subjects were segmented and used for Monte Carlo (MC) simulation. We evaluated effects of optical properties and abscess morphology on PDT eligibility and generated treatment plans.

APPROACH

A range of abscess wall absorptions (μa , wall) and intra-cavity Intralipid concentrations were simulated. At each combination, the threshold optical power and optimal Intralipid concentration were found for a fluence rate target, with subjects being eligible for PDT if the target was attainable with <2000 mW of source light. Further simulations were performed with absorption within the cavity (μa , cavity).

RESULTS

Patient-specific treatment planning substantially increased the number of subjects expected to achieve an efficacious light dose for antimicrobial PDT, especially with Intralipid modification. The threshold optical power and optimal Intralipid concentration increased with increasing μa , wall (p < 0.001). PDT eligibility improved with patient-specific treatment planning (p < 0.0001). With μa , wall = 0.2 cm - 1, eligibility increased from 42% to 92%. Increasing μa , cavity reduced PDT eligibility (p < 0.0001); modifying the delivered optical power had the greatest impact in this case.

CONCLUSIONS

MC-based treatment planning greatly increases eligibility for PDT of abscess cavities.

意义

抗菌光动力疗法（PDT）可有效杀死深部组织脓肿腔中的细菌株。PDT 反应取决于多种因素，包括光剂量，这取决于患者的光学特性。

目的

对 60 名脓肿引流患者的 CT 图像进行分割，并用于蒙特卡罗（MC）模拟。我们评估了光学特性和脓肿形态对 PDT 资格的影响，并生成了治疗计划。

方法

模拟了一系列脓肿壁吸收率（μa 壁）和腔内 Intralipid 浓度。在每种组合下，都找到了达到目标辐照度所需的阈值光功率和最佳 Intralipid 浓度，当目标可以用<2000 mW 的光源光实现时，患者有资格接受 PDT。进一步用腔内吸收（μa 腔）进行模拟。

结果

个体化治疗计划大大增加了预计能达到抗菌 PDT 有效光剂量的患者数量，特别是通过 Intralipid 修饰。随着 μa 壁的增加（p<0.001），阈值光功率和最佳 Intralipid 浓度均增加。个体化治疗计划改善了 PDT 的资格（p<0.0001）。当 μa 壁=0.2 cm-1 时，符合条件的患者比例从 42%增加到 92%。增加 μa 腔会降低 PDT 的资格（p<0.0001）；在这种情况下，改变传输的光功率影响最大。