Dual-modality needle probe for combined fluorescence imaging and three-dimensional optical coherence tomography

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Optical Physics

Background:

• Optical coherence tomography (OCT) provides high-resolution cross-sectional imaging.
• Fluorescence imaging offers molecular and functional information.
• Combining imaging modalities can enhance diagnostic capabilities.

Purpose of the Study:

• To develop and validate a novel needle probe for simultaneous OCT and fluorescence imaging.
• To demonstrate the capability of the dual-modality probe for in-situ tissue characterization.
• To improve tissue differentiation compared to OCT alone.

Main Methods:

• A double-clad fiber (DCF) based needle probe was designed to guide OCT signals and fluorescence excitation/emission.
• A 1310 nm swept-source OCT system was modified for simultaneous fluorescence excitation (488 nm) and detection (>500 nm).
• A DCF coupler was utilized for efficient collection of returning fluorescence signals.

Main Results:

• The probe successfully guided both OCT signals and fluorescence excitation/emission.
• Imaging of excised sheep lung vasculature with fluorescein demonstrated visualization of alveoli, bronchioles, and blood vessels.
• Combined OCT and fluorescence imaging provided superior tissue differentiation compared to OCT alone.

Conclusions:

• The developed needle probe enables simultaneous OCT and fluorescence imaging.
• This dual-modality approach offers enhanced capabilities for visualizing microstructures and molecular information.
• The technology shows promise for improved diagnostic accuracy in various biomedical applications.