A birefringent spectral demultiplexer enables fast hyper-spectral imaging of protoporphyrin IX during neurosurgery

Commun Biol. 2023 Mar 30;6(1):341. doi: 10.1038/s42003-023-04701-9.

Abstract

Hyperspectral imaging and spectral analysis quantifies fluorophore concentration during fluorescence-guided surgery1-6. However, acquisition of the multiple wavelengths required to implement these methods can be time-consuming and hinder surgical workflow. To this end, a snapshot hyperspectral imaging system capable of acquiring 64 channels of spectral data simultaneously was developed for rapid hyperspectral imaging during neurosurgery. The system uses a birefringent spectral demultiplexer to split incoming light and redirect wavelengths to different sections of a large format microscope sensor. Its configuration achieves high optical throughput, accepts unpolarized input light and exceeds channel count of prior image-replicating imaging spectrometers by 4-fold. Tissue-simulating phantoms consisting of serial dilutions of the fluorescent agent characterize system linearity and sensitivity, and comparisons to performance of a liquid crystal tunable filter based hyperspectral imaging device are favorable. The new instrument showed comparable, if not improved, sensitivity at low fluorophore concentrations; yet, acquired wide-field images at more than 70-fold increase in frame rate. Image data acquired in the operating room during human brain tumor resection confirm these findings. The new device is an important advance in achieving real-time quantitative imaging of fluorophore concentration for guiding surgery.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Brain Neoplasms* / diagnostic imaging
  • Brain Neoplasms* / surgery
  • Fluorescent Dyes
  • Humans
  • Neurosurgery*
  • Optical Imaging / methods
  • Protoporphyrins

Substances

  • protoporphyrin IX
  • Protoporphyrins
  • Fluorescent Dyes