Work

Single-distance, phase-only frequency-domain NIRS for vascular oxygenation and tissue metabolism: a Monte Carlo simulation study

Year: 2025

Type: article

Abstract: SignificanceFrequency-domain near-infrared spectroscopy (FD-NIRS) currently enables absolute hemoglobin quantification but requires multidistance measurements of both amplitude attenuation and phase shifts. Notably, existing FD-NIRS approaches have not demonstrated reliable quantification of differential redox-state concentrations of cytochrome c oxidase (CCOredox), a critical metabolic marker.AimWe aimed to develop a novel optimization-based algorithm for single source-detector (S-D), phase-only FD-NIRS that achieves accurate quantifications of hemoglobin parameters (HbO and Hb) and CCOredox.ApproachOur computational framework implemented both forward modeling and inverse reconstruction. For the modeling, we first defined chromophore concentration sets (HbO, Hb, CCOredox), followed by calculations of wavelength-dependent optical properties for two- or eight-wavelength configurations. Next, time-domain photon propagation was generated via Monte Carlo (MC) simulations, and FD-NIRS parameters (modulation amplitude, phase) were extracted through Fourier analysis. In the inverse computation, nonlinear optimization with edge-barrier regularization was employed for the recovery of chromophore concentrations. Both the multiseparation method and the single S-D, phase-only algorithm were used to reconstruct chromophore concentrations.ResultsRespective performances evaluated for the two methods were compared through their concentration recovery accuracy. In either the two- or eight-wavelength configuration, our new algorithm outperformed the conventional method for the S-D separations up to 3 cm for all three chromophores. In particular, CCOredox estimation was improved markedly from a mean relative error of 34.1% with the conventional method to just 5.1% using our algorithm.ConclusionsThese results validate single-separation phase-only FD-NIRS as an accurate method for multichromophore quantification (including CCOredox), enabling simpler, cost-effective systems without compromising metabolic imaging capability. The approach achieves <10% error in hemoglobin quantification while eliminating traditional multidistance requirements.

Source: Journal of Biomedical Optics

DOI: 10.1117/1.jbo.30.s3.s34113

Authors: Muaaz Faiyazuddin, Haiyang Tang, Yiqing Hu, Miles Bartlett, Michael D. Nelson, Hanli Liu

Institution: The University of Texas at Arlington

Language: English

Topic: Optical Imaging and Spectroscopy Techniques

Subfield: Radiology, Nuclear Medicine and Imaging

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $1,675