Development of a handheld compression optical coherence elastography probe with a disposable stress sensor

Area of Science:

• Biomedical Optics
• Medical Imaging
• Biophysics

Background:

• Optical coherence elastography (OCE) extends optical coherence tomography (OCT) by measuring tissue deformation under applied forces.
• Quantitative force measurement is crucial for accurate elastography but often challenging with existing OCT-based methods.
• Existing OCE techniques frequently rely on external force sensors, limiting portability and in vivo applications.

Purpose of the Study:

• To develop a handheld, quantitative compression OCE probe incorporating a novel integrated stress sensor.
• To enable precise measurement of applied forces during OCE examinations.
• To evaluate the probe's capability for measuring tissue elasticity, including in vivo human skin.

Main Methods:

• Development of a novel stress sensor using a glass window, metal ring, and polyurethane spokes, integrated into the OCT probe tip.
• Utilizing OCT imaging to detect window displacement for force calculation, calibrated via simulation and experimental methods.
• Employing phase-sensitive OCT to measure both window displacement and sample deformation for elasticity assessment.

Main Results:

• The novel stress sensor accurately measures applied force by correlating window displacement with force.
• The developed OCE probe demonstrated high capability in measuring the Young's modulus of a two-layer phantom.
• Successful in vivo measurement of human fingertip elasticity was achieved, validating the probe's potential for skin elastography.

Conclusions:

• The developed handheld quantitative compression OCE probe with an integrated stress sensor offers a portable and accurate solution for elasticity measurements.
• This technology shows significant promise for non-invasive, in vivo elastography of human skin and potentially other soft tissues.
• The integrated stress sensing mechanism enhances the quantitative capabilities of OCE for biomedical applications.