Frequency domain optoacoustic tomography using amplitude and phase

Area of Science:

• Biomedical Imaging
• Optoacoustic Imaging
• Medical Physics

Background:

• Optoacoustic imaging offers non-ionizing, high-contrast visualization of biological tissues.
• Traditional time-domain optoacoustics relies on pulsed laser excitation.
• Frequency-domain approaches may offer alternative advantages in data acquisition and processing.

Purpose of the Study:

• To introduce and evaluate frequency-domain optoacoustic tomography (FD-OAT).
• To investigate the impact of modulation frequencies and bandwidth on image quality.
• To assess the feasibility of FD-OAT for experimental measurements, considering noise levels.

Main Methods:

• Utilizing intensity-modulated light sources for optoacoustic signal generation.
• Acquiring amplitude and phase information in the frequency domain across multiple modulation frequencies.
• Employing Green's function solution for forward modeling in the frequency domain.
• Solving the inverse problem using regularized least squares minimization.

Main Results:

• Image quality is influenced by the number of frequencies and the employed bandwidth.
• The study analyzed the performance of FD-OAT as a function of noise for experimental feasibility.
• Demonstrated the potential for high-quality imaging using frequency-domain data.

Conclusions:

• Frequency-domain optoacoustic tomography is a viable imaging modality.
• The method shows potential advantages over traditional time-domain optoacoustics.
• FD-OAT may become a practical experimental technique with further development.