Dataset Information

In vivo spectroscopic evaluation of human tissue optical properties and hemodynamics during HPPH-mediated photodynamic therapy of pleural malignancies.

ABSTRACT:

Significance

Dosimetry for photodynamic therapy is dependent on multiple parameters. Critically, in vivo tissue optical properties and hemodynamics must be determined carefully to calculate the total delivered light dose.

Aim

Spectroscopic analysis of diffuse reflectance measurements of tissues taken during a clinical trial of 2-(1-hexyloxyethyl)-2-devinyl pyropheophorbide-a-mediated photodynamic therapy for pleural malignancies.

Approach

Diffuse reflectance measurements were taken immediately before and after photodynamic therapy. Measurements were analyzed with a nonlinearly constrained multiwavelength, multi-distance algorithm to extract tissue optical properties, tissue oxygen saturation, StO2, and total hemoglobin concentration (THC).

Results

A total of 25 patients were measured, 23 of which produced reliable fits for optical property extraction. For all tissue types, StO2 ranged through [24, 100]% and [22, 97]% for pre-photodynamic therapy (PDT) and post-PDT conditions, respectively. Mean THC ranged through [ 69,152 ] μM and [ 48,111 ] μM, for pre-PDT and post-PDT, respectively. Absorption coefficients, μa, ranged through [ 0.024 , 3.5 ] cm - 1 and [ 0.039 , 3 ] cm - 1 for pre-PDT and post-PDT conditions, respectively. Reduced scattering coefficients, μs', ranged through [ 1.4 , 73.4 ] cm - 1 and [ 1.2 , 64 ] cm - 1 for pre-PDT and post-PDT conditions, respectively.

Conclusions

There were similar pre- and post-PDT tissue optical properties and hemodynamics. The high variability in each parameter for all tissue types emphasizes the importance of these measurements for accurate PDT dosimetry.

SUBMITTER: Morales RDH

PROVIDER: S-EPMC9621284 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Publications

In vivo spectroscopic evaluation of human tissue optical properties and hemodynamics during HPPH-mediated photodynamic therapy of pleural malignancies.

Morales Ryan D Hall RDH Hong Ong Yi Y Finlay Jarod J Dimofte Andreea A Simone Charles B CB Friedberg Joseph S JS Busch Theresa M TM Cengel Keith A KA Zhu Timothy C TC

Journal of biomedical optics 20221001 10

<h4>Significance</h4>Dosimetry for photodynamic therapy is dependent on multiple parameters. Critically, in vivo tissue optical properties and hemodynamics must be determined carefully to calculate the total delivered light dose.<h4>Aim</h4>Spectroscopic analysis of diffuse reflectance measurements of tissues taken during a clinical trial of 2-(1-hexyloxyethyl)-2-devinyl pyropheophorbide-a-mediated photodynamic therapy for pleural malignancies.<h4>Approach</h4>Diffuse reflectance measurements we ...[more]

PMID: 36316298

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Dataset Information

In vivo spectroscopic evaluation of human tissue optical properties and hemodynamics during HPPH-mediated photodynamic therapy of pleural malignancies.

Significance

Aim

Approach

Results

Conclusions

Publications

In vivo spectroscopic evaluation of human tissue optical properties and hemodynamics during HPPH-mediated photodynamic therapy of pleural malignancies.

Similar Datasets

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