Liquid-crystal tunable filter spectral imaging for brain tumor demarcation

Area of Science:

• Biomedical Optics
• Surgical Guidance Technologies
• Medical Imaging

Background:

• Previous studies utilized combined fluorescence and diffuse reflectance spectroscopy for brain tissue discrimination.
• Real-time surgical resection guidance requires extending probe-based spectroscopy to spectral imaging for spatial demarcation of tumor margins.

Purpose of the Study:

• To design and characterize a spectral imaging system for real-time surgical resection guidance.
• To evaluate the system's performance in discriminating between normal and tumorous brain tissues.

Main Methods:

• Development of a combined fluorescence and diffuse reflectance imaging system utilizing liquid-crystal tunable filter technology.
• Quantitative characterization of linearity, field of view, spatial/spectral resolution, and wavelength sensitivity.
• Functional testing using tissue phantoms, ex vivo mouse brain, and in vivo human cortex.

Main Results:

• The system demonstrated linear intensity response with sample emission and integration time.
• Achieved a 1-inch field of view and pixel-limited spatial resolution.
• Successfully spectrally discriminated between brain tissues in vitro and captured adequate in vivo data within a 2-minute timeframe.

Conclusions:

• The developed spectral imaging system is capable of real-time, spatially resolved optical biopsy for brain tumor margin delineation.
• The system's performance is influenced by factors such as hemostasis, impacting signal strength and imaging speed.
• This technology holds promise for enhancing surgical precision in neuro-oncology.