X-ray-induced shortwave infrared luminescence computed tomography

Area of Science:

• Medical Imaging
• Nanotechnology
• Biophysics

Background:

• X-ray luminescence computed tomography (XLCT) is a novel molecular imaging modality.
• XLCT offers advantages over fluorescence imaging, including reduced autofluorescence and deep-tissue penetration.
• Current XLCT typically operates in the visible or infrared spectrum.

Purpose of the Study:

• To extend XLCT to the shortwave infrared (SWIR) spectral region.
• To develop SWIR-XLCT for enhanced deep-tissue in vivo imaging.
• To synthesize and characterize novel nanophosphors for SWIR emission under X-ray excitation.

Main Methods:

• Synthesis of core/shell rare-earth nanophosphors (RENPs): Ho-doped NaYbF4 core and NaYF4 shell.
• X-ray excitation of RENPs to generate shortwave infrared luminescence.
• Numerical simulations and phantom experiments to validate SWIR-XLCT feasibility.
• Evaluation of imaging performance, including spatial resolution and depth penetration.

Main Results:

• Successfully developed SWIR-XLCT by utilizing RENPs emitting in the shortwave infrared region.
• Demonstrated feasibility of SWIR-XLCT through simulations and phantom studies.
• Achieved high spatial resolution and deep depth imaging capabilities in phantom experiments.
• Confirmed reduced autofluorescence and enhanced optical contrast compared to conventional methods.

Conclusions:

• SWIR-XLCT is a feasible and promising imaging modality for deep-tissue molecular imaging.
• The developed RENPs are effective for X-ray-induced SWIR luminescence.
• SWIR-XLCT offers significant potential for advancing in vivo molecular imaging with high resolution and depth penetration.