Macroscopic-imaging technique for subsurface quantification of near-infrared markers during surgery

J Biomed Opt. 2015 Mar;20(3):036014. doi: 10.1117/1.JBO.20.3.036014.

Abstract

Obtaining accurate quantitative information on the concentration and distribution of fluorescent markers lying at a depth below the surface of optically turbid media, such as tissue, is a significant challenge. Here, we introduce a fluorescence reconstruction technique based on a diffusion light transport model that can be used during surgery, including guiding resection of brain tumors, for depth-resolved quantitative imaging of near-infrared fluorescent markers. Hyperspectral fluorescence images are used to compute a topographic map of the fluorophore distribution, which yields structural and optical constraints for a three-dimensional subsequent hyperspectral diffuse fluorescence reconstruction algorithm. Using the model fluorophore Alexa Fluor 647 and brain-like tissue phantoms, the technique yielded estimates of fluorophore concentration within ±25% of the true value to depths of 5 to 9 mm, depending on the concentration. The approach is practical for integration into a neurosurgical fluorescence microscope and has potential to further extend fluorescence-guided resection using objective and quantified metrics of the presence of residual tumor tissue.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms*
  • Brain Neoplasms / chemistry
  • Brain Neoplasms / diagnostic imaging*
  • Brain Neoplasms / surgery
  • Fluorescent Dyes / analysis
  • Humans
  • Image Processing, Computer-Assisted
  • Neoplasm, Residual
  • Optical Imaging / methods*
  • Phantoms, Imaging
  • Sensitivity and Specificity
  • Spectrometry, Fluorescence
  • Spectroscopy, Near-Infrared

Substances

  • Fluorescent Dyes