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Updated: Feb 3, 2026
14:21
Optical Frequency Domain Imaging of Ex vivo Pulmonary Resection Specimens: Obtaining One to One Image to Histopathology Correlation
Published on: January 22, 2013
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Quantitative subsurface spatial frequency-domain fluorescence imaging for enhanced glioma resection.
Mira Sibai1,2, Dennis J Wirth3, Frederic Leblond4
1Princess Margaret Cancer Center, University Health Network, Toronto, Ontario, Canada.
Journal of Biophotonics
|October 26, 2018
Summary
This study improves glioma resection by measuring subsurface 5-aminolevulinic acid-induced protoporphyrin IX (PpIX) concentration using red-light excitation. This technique accurately quantifies PpIX depth and concentration in brain phantoms, enhancing surgical guidance.
Area of Science:
- Biomedical Optics
- Surgical Guidance
- Cancer Diagnostics
Background:
- 5-aminolevulinic acid (5-ALA) induces protoporphyrin IX (PpIX) fluorescence, aiding glioma resection.
- Previous methods measured near-surface PpIX; this study extends to subsurface measurements.
- Decoupling fluorescence from tissue optical properties yields absolute PpIX concentration ([PpIX]).
Discussion:
- Spatial frequency domain imaging with red-light excitation estimates subsurface PpIX.
- Modulation amplitude decay determines PpIX depth, enabling accurate concentration mapping.
- Brain-like phantoms validated depth recovery up to 9.5 mm.
Key Insights:
- Accurate subsurface [PpIX] quantification is achievable using red-light excitation.
- The method recovers PpIX depth and concentration with an average 15% deviation.
- This technique offers improved precision for intraoperative glioma margin assessment.
Outlook:
- Potential for real-time, in vivo subsurface PpIX measurements during surgery.
- Further validation in clinical settings is warranted.
- This technology could significantly improve complete tumor resection rates and patient outcomes.
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