Depth-encoded optical coherence elastography for simultaneous volumetric imaging of two tissue faces

Area of Science:

• Biomedical Optics
• Medical Imaging
• Biophysics

Background:

• Optical Coherence Elastography (OCE) is a powerful technique for non-invasively measuring tissue mechanical properties.
• Simultaneous imaging from multiple surfaces can improve accuracy and reduce acquisition time.
• Current OCE methods often require complex setups or longer scan durations.

Purpose of the Study:

• To introduce and validate a novel depth-encoded OCE technique.
• To demonstrate simultaneous acquisition of two 3D elastograms from opposite sample surfaces.
• To assess the potential for reducing hardware requirements and scan time.

Main Methods:

• Developed a depth-encoded OCE system utilizing two interferometers with distinct path-length differences.
• Separated carrier frequencies to enable simultaneous depth-ranging from each interferometer using a single spectrometer.
• Validated the technique on a silicone phantom and an ex vivo mouse liver sample.

Main Results:

• Successfully acquired two simultaneous 3D elastograms from opposite sides of samples.
• Demonstrated effective depth-ranging and frequency separation.
• Achieved a reduction in required spectral detection hardware and halved the total scan time.

Conclusions:

• Depth-encoded OCE enables efficient, simultaneous 3D mechanical property mapping.
• The technique offers significant advantages in speed and hardware simplification.
• This method holds promise for accelerating clinical translation in time-sensitive applications like tumor margin assessment.