Transport-based image reconstruction in turbid media with small source-detector separations

Area of Science:

• Biomedical optics
• Medical imaging
• Optical microscopy

Background:

• Imaging through turbid media remains a significant challenge in various scientific fields.
• Confocal microscopy offers high resolution but is limited by scattering.
• Diffuse optical tomography (DOT) can penetrate scattering media but typically lacks high resolution.

Purpose of the Study:

• To develop and demonstrate a hybrid imaging method for high-resolution imaging in turbid samples.
• To combine the strengths of confocal reflectance microscopy and diffuse optical tomography.
• To achieve imaging of subsurface structures within millimeters of depth.

Main Methods:

• Integration of confocal reflectance microscopy with diffuse optical tomography principles.
• Lateral displacement of the confocal pinhole to enable small source-detector separations.
• Utilizing minimally scattered light detection.
• Employing a reconstruction algorithm based on the first Born approximation to the radiative transport equation.

Main Results:

• Successful imaging through several millimeters of a turbid sample.
• Achieved an approximate resolution of 100 micrometers.
• Reconstructed an image of a 100-micrometer absorbing object situated 2 mm beneath the sample surface.

Conclusions:

• The demonstrated hybrid imaging method effectively overcomes the limitations of scattering in turbid media.
• This technique provides a promising approach for high-resolution subsurface imaging.
• Potential applications in biological tissue imaging and material science are suggested.