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Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems

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Published on: February 10, 2020

Time-resolved near infrared light propagation using frequency domain superposition.

Stanislaw Wojtkiewicz¹, Turgut Durduran^2,3, Hamid Dehghani¹

¹School of Computer Science, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.

Biomedical Optics Express

|January 24, 2018

Summary

This study introduces an efficient frequency domain method to speed up time-resolved temporal point spread function (TPSF) calculations for near-infrared spectroscopic (NIRS) imaging. The new approach significantly accelerates tissue property estimation in biological models.

Keywords:

(170.3660) Light propagation in tissues (170.5270) Photon density waves

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Area of Science:

Biomedical Optics
Computational Modeling
Medical Imaging

Background:

Near-infrared spectroscopy (NIRS) enables non-invasive tissue property estimation via time-resolved temporal point spread function (TPSF) measurements.
Accurate TPSF analysis relies on computationally intensive iterative calculations using mathematical and finite element models.

Purpose of the Study:

To develop an efficient computational methodology for TPSF data representation.
To accelerate the calculation of TPSF for improved biological tissue analysis.

Main Methods:

Representing TPSF data using a superposition of cosines in the frequency domain.
Testing the proposed method on finite element models of the human head and neck.

Main Results:

The frequency domain cosine superposition method was successfully implemented and validated on realistic human models.
TPSF calculation time for an adult head model (~140k nodes) was reduced from 3.11s to 1.29s per source.
The accelerated method maintained accuracy within a ±5% error margin compared to time-domain calculations.

Conclusions:

The proposed frequency domain method offers a computationally efficient alternative for TPSF analysis in NIRS.
This acceleration can significantly benefit the application of NIRS in biological tissue imaging and diagnostics.