Combined autofluorescence and diffuse reflectance for brain tumour surgical guidance: initial ex vivo study results

Huihui Lu; Konstantin Grygoryev; Niamh Bermingham; Michael Jansen; Michael O'Sullivan; Gerard Nunan; Kevin Buckley; Kevin Manley; Ray Burke; Stefan Andersson-Engels

doi:10.1364/BOE.420292

Combined autofluorescence and diffuse reflectance for brain tumour surgical guidance: initial ex vivo study results

Biomed Opt Express. 2021 Mar 29;12(4):2432-2446. doi: 10.1364/BOE.420292. eCollection 2021 Apr 1.

Authors

Affiliations

¹ Biophotonics @ Tyndall, IPIC, Tyndall National Institute, University College Cork, Cork, Ireland.
² Department of Neuropathology, Cork University Hospital, Cork, Ireland.
³ Department of Neurosurgery, Cork University Hospital, Cork, Ireland.
⁴ Stryker, Instruments Innovation Centre, IDA Business and Technology Park, Cork, Ireland.
⁵ Department of Physics, University College Cork, Cork, Ireland.

Abstract

This ex vivo study was conducted to assess the potential of using a fibre optic probe system based on autofluorescence and diffuse reflectance for tissue differentiation in the brain. A total of 180 optical measurements were acquired from 28 brain specimens (five patients) with eight excitation and emission wavelengths spanning from 300 to 700 nm. Partial least square-linear discriminant analysis (PLS-LDA) was used for tissue discrimination. Leave-one-out cross validation (LOOCV) was then used to evaluate the performance of the classification model. Grey matter was differentiated from tumour tissue with sensitivity of 89.3% and specificity of 92.5%. The variable importance in projection (VIP) derived from the PLS regression was applied to wavelengths selection, and identified the biochemical sources of the detected signals. The initial results of the study were promising and point the way towards a cost-effective, miniaturized hand-held probe for real time and label-free surgical guidance.