Overview of diffuse optical tomography and its clinical applications

Area of Science:

• Biomedical optics
• Medical imaging
• Optical engineering

Background:

• Near-infrared diffuse optical tomography (DOT) is an advanced optical imaging technique for 3-D quantitative imaging of biological tissues.
• DOT aims to overcome the limitations of near-infrared spectroscopy (NIRS) and enable diagnostic optical imaging.
• DOT development faces challenges due to strong light scattering and the use of diffusive photons in image reconstruction.

Purpose of the Study:

• To review near-infrared spectroscopy (NIRS).
• To describe various approaches for developing accurate and efficient DOT algorithms.
• To present examples of clinical applications and discuss future prospects of DOT.

Main Methods:

• Summarizing NIRS principles and limitations.
• Describing DOT algorithm development, including inverse problem techniques.
• Discussing the use of the diffusion equation (DE) as a forward model and its limitations compared to the radiative transfer equation.
• Presenting clinical applications and future outlook.

Main Results:

• DOT allows 3-D quantitative imaging of optical properties, providing functional and anatomical information.
• The diffusion equation (DE) is often used as a computationally efficient forward model, but it has limitations in certain regions.
• The inherent ill-posed and undetermined nature of the inverse problem presents significant challenges in DOT algorithm development.

Conclusions:

• DOT is a sophisticated technique with the potential for diagnostic imaging, offering advantages over NIRS.
• Accurate and efficient DOT algorithm development is crucial for overcoming challenges related to light scattering and inverse problems.
• Continued research and development are expected to enhance DOT's clinical applicability and future prospects.