Sensitivity characterization of a time-domain fluorescence imager: eXplore Optix

Area of Science:

• Biomedical Optics
• Medical Imaging Technology
• Fluorescence Imaging

Background:

• Background signals in fluorescence imaging reduce detection sensitivity, particularly for in vivo applications.
• Eliminating background noise completely is a persistent challenge across all fluorescence imaging technologies.

Purpose of the Study:

• To develop and present a novel methodology for characterizing fluorescence imaging device sensitivity.
• To incorporate the impact of background signals into sensitivity assessments using the signal-to-background ratio (SBR).

Main Methods:

• Experimental investigation using tissuelike liquid phantoms with Cy5.5 fluorescent inclusions.
• Systematic variation of parameters including tissue optical properties (absorption, scattering), fluorophore concentration, and inclusion location.
• Definition and application of detectable and quantifiable SBR thresholds.

Main Results:

• Established empirical relations between imaging parameters and SBR.
• Characterized the sensitivity performance of the Advanced Research Technologies's eXplore Optix system using Cy5.5.
• Demonstrated the effectiveness of the SBR methodology in accounting for background effects.

Conclusions:

• The proposed SBR methodology provides a robust framework for evaluating fluorescence imaging sensitivity.
• Accurate characterization of imaging systems is essential for reliable in vivo fluorescence imaging.
• This approach enhances the understanding and optimization of fluorescence imaging systems for biomedical applications.