Monte Carlo photon-transport modelling of diffuse reflectance spectroscopy in heterogenous lymph node models
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
Intraoperative assessment of lymph node metastasis remains a major challenge during cancer surgery. Diffuse Reflectance Spectroscopy (DRS) is a point-based technique that has the potential to offer rapid diagnosis, but the technological limits of this technique have not been well defined for this application. We acquired over 11000 spectra from 99 lymph nodes excised from 26 patients undergoing gastric or oesophageal cancer resection, and utilised these to derive optical properties for benign node, malignant node and adipose tissue. Monte Carlo simulations were then utilised to model photon transport in a wide array of simulated nodes with varying metastatic focus sizes and depths, lymph node sizes and depths, and DRS probe source-detector separations. Our simulations demonstrated a ‘thoretical minimum’ micrometastatic focus detectable by DRS of approximately 350–600 μm. Increasing source-detector separation extended the depth of probing but raised the minimum focus diameter detectable with DRS, indicating a trade-off effect between depth penetration and micrometastasis detection. Our findings reveal the potential for DRS to be utilised as a real-time intraoperative spectroscopic method for the detection of lymph node metastases, and establish the basis for DRS probe design optimisation.
Date Issued
2026-07
Date Acceptance
2025-12-23
Citation
IEEE Journal of Selected Topics in Quantum Electronics, 2026, 32 (4)
ISSN
1077-260X
Publisher
Institute of Electrical and Electronics Engineers (IEEE)
Start Page
1
End Page
12
Journal / Book Title
IEEE Journal of Selected Topics in Quantum Electronics
Volume
32
Issue
4
Copyright Statement
Copyright © 2025 IEEE. This is the author’s accepted manuscript made available under a CC-BY licence in accordance with Imperial’s Research Publications Open Access policy (www.imperial.ac.uk/oa-policy)
License URL
Publication Status
Published
Date Publish Online
2025-12-30