Direct reconstruction method for time-domain fluorescence molecular lifetime tomography.

Area of Science:

• Biomedical Optics
• Medical Imaging
• Fluorescence Spectroscopy

Background:

• Conventional time-domain fluorescence molecular lifetime tomography methods often discard valuable measurement data.
• Existing techniques rely on transformations like Laplace or Fourier, limiting information utilization and requiring specific factor selection.

Purpose of the Study:

• To develop a direct reconstruction algorithm for time-domain fluorescence molecular lifetime tomography.
• To maximize the use of all available measurement data for improved accuracy.
• To address limitations of existing methods, particularly regarding data utilization and image singularity.

Main Methods:

• A direct reconstruction algorithm is proposed, bypassing traditional transform-based approaches.
• The algorithm first reconstructs the fluorescence yield map using a full-time gate.
• An objective function is developed for inverse lifetime tomography, avoiding lifetime image singularity issues.

Main Results:

• The algorithm demonstrates high localization accuracy for fluorescent targets in simulations and phantom experiments.
• Accurate quantification of fluorescence lifetime is achieved.
• Good contrast is observed between different fluorescence targets, indicating improved image quality.

Conclusions:

• The proposed direct reconstruction algorithm offers a significant advancement in time-domain fluorescence molecular lifetime tomography.
• It effectively utilizes all measurement data, leading to superior localization and quantification accuracy.
• This method provides better contrast and overcomes limitations of conventional transform-based techniques.