首次通过漫反射光谱法在人体中测量光动力治疗前脓肿腔的光学特性和亚甲蓝摄取量。

First in human measurements of abscess cavity optical properties and methylene blue uptake prior to photodynamic therapy by diffuse reflectance spectroscopy.

作者信息

Hannan Md Nafiz, Sharma Ashwani K, Baran Timothy M

出版信息

medRxiv. 2023 Oct 16:2023.10.16.23297088. doi: 10.1101/2023.10.16.23297088.

DOI:10.1101/2023.10.16.23297088

PMID:37905076

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10615020/

Abstract

SIGNIFICANCE

Efficacious photodynamic therapy (PDT) of abscess cavities requires personalized treatment planning. This relies on knowledge of abscess wall optical properties, which we report for the first time in human subjects.

AIM

The objective was to extract optical properties and photosensitizer concentration from spatially-resolved diffuse reflectance measurements of abscess cavities prior to methylene blue (MB) PDT, as part of a Phase 1 clinical trial.

APPROACH

Diffuse reflectance spectra were collected at the abscess wall of 13 human subjects using a custom fiber-optic probe and optical spectroscopy system, before and after MB administration. A Monte Carlo lookup table was used to extract optical properties.

RESULTS

Pre-MB abscess wall absorption coefficients at 665 nm were 0.15±0.1 cm (0.03-0.36 cm ) and 10.74±15.81 cm (0.08-49.3 cm ) post-MB. Reduced scattering coefficients at 665 nm were 8.45±2.37 cm (4.8-13.2 cm ) and 5.6±2.26 cm (1.6-9.9 cm ) for pre-MB and post-MB, respectively. Oxygen saturations were found to be 58.83±35.78% (5.6-100%) pre-MB and 36.29±25.1% (0.0001-76.4%) post-MB. Determined MB concentrations were 71.83±108.22 µM (0-311 µM).

CONCLUSIONS

We observed substantial inter-subject variation in both native wall optical properties and methylene blue uptake. This underscores the importance of making these measurements for patient-specific treatment planning.

摘要

意义

脓肿腔的有效光动力疗法（PDT）需要个性化的治疗方案。这依赖于脓肿壁光学特性的知识，我们首次在人体受试者中报告了这一特性。

目的

作为1期临床试验的一部分，目标是在亚甲蓝（MB）光动力疗法之前，从脓肿腔的空间分辨漫反射测量中提取光学特性和光敏剂浓度。

方法

在13名人体受试者的脓肿壁上，使用定制的光纤探头和光学光谱系统，在给予MB之前和之后收集漫反射光谱。使用蒙特卡罗查找表提取光学特性。

结果

MB给药前，665nm处脓肿壁的吸收系数为0.15±0.1cm⁻¹（0.03 - 0.36cm⁻¹），给药后为10.74±15.81cm⁻¹（0.08 - 49.3cm⁻¹）。665nm处的约化散射系数，给药前为8.45±2.37cm⁻¹（4.8 - 13.2cm⁻¹），给药后为5.6±2.26cm⁻¹（1.6 - 9.9cm⁻¹）。发现氧饱和度给药前为58.83±35.78%（5.6 - ～100%），给药后为～36.29±25.1%（0.0001 - 76.4%）。测定的MB浓度为71.83±108.22μM（0 - 311μM）。