Multispectral analog-mean-delay fluorescence lifetime imaging combined with optical coherence tomography

Area of Science:

• Biomedical Optics
• Medical Imaging
• Biophotonics

Background:

• Chronic diseases like atherosclerosis and cancer involve compositional changes in biological tissues.
• These changes are linked to endogenous fluorophores (collagen, elastin, NADH) and their autofluorescence.
• Fluorescence lifetime imaging (FLIm) detects these compositional shifts by measuring fluorescence lifetime.

Purpose of the Study:

• To present a dual-modality system integrating multispectral analog-mean-delay (AMD) FLIm and swept-source optical coherence tomography (OCT).
• To enable simultaneous visualization of cross-sectional morphology and biochemical composition in biological tissues.
• To demonstrate the system's potential for diagnosing atherosclerosis and cancer.

Main Methods:

• Developed a dual-modality system combining multispectral AMD-FLIm and high-speed swept-source OCT.
• Measured fluorescence lifetime with a precision of <40 psec using multispectral AMD-FLIm without averaging.
• Performed ex vivo imaging on rabbit iliac normal and atherosclerotic specimens.

Main Results:

• The combined FLIm-OCT system successfully visualized both morphology and biochemical composition.
• Multispectral AMD-FLIm achieved high precision in fluorescence lifetime measurements (<40 psec).
• Ex vivo imaging demonstrated the system's feasibility for atherosclerosis detection.

Conclusions:

• The combined FLIm-OCT system offers simultaneous, label-free imaging of tissue morphology and biochemical composition.
• This technology provides high-precision multispectral lifetime measurements.
• The system shows promise as a next-generation tool for diagnosing atherosclerosis and cancer.