Optical wavelength selection for improved spectroscopic photoacoustic imaging

Area of Science:

• Biomedical Optics
• Medical Imaging
• Spectroscopy

Background:

• Spectroscopic photoacoustic imaging estimates chromophore distributions in vivo.
• Accurate wavelength selection is crucial for quantitative spectroscopic photoacoustic imaging.
• Existing methods may not be optimal in complex biological environments.

Purpose of the Study:

• To develop and validate an algorithm for selecting optimal imaging wavelengths in spectroscopic photoacoustic imaging.
• To improve the accuracy of estimating chromophore concentrations and distributions.
• To provide a versatile framework for wavelength selection and absorber evaluation.

Main Methods:

• Developed an algorithm using the smallest singular value of a matrix derived from absorption spectra to select wavelengths.
• Compared the algorithm's performance against evenly spaced wavelengths under simulated noise and wavelength-dependent attenuation.
• Applied the algorithm to photoacoustic imaging of phantoms with known absorbers.

Main Results:

• The proposed algorithm significantly outperformed evenly spaced wavelengths in simulated scenarios with noise and attenuation.
• Demonstrated improved estimation of relative contrast agent concentrations in phantom studies.
• The algorithm effectively selected wavelengths for differentiating between indocyanine green and gold nanorods.

Conclusions:

• The developed algorithm provides a robust and versatile method for selecting optimal wavelengths in spectroscopic photoacoustic imaging.
• This approach enhances the quantitative accuracy of chromophore and contrast agent concentration measurements.
• The framework supports the evaluation of absorber sets for improved spectroscopic photoacoustic imaging applications.