Visualization of Breast Cancer Using Contrast-Enhanced Optical Coherence Elastography Based on Tissue Heterogeneity.

Area of Science:

• Biomedical Optics
• Medical Imaging
• Biophysics

Background:

• Elastography enhances breast cancer identification by mapping tissue mechanical properties.
• Current optical coherence elastography (OCE) methods rely on uniaxial stress assumptions, limiting accuracy in heterogeneous breast tissue.
• Breast tissue's heterogeneity, including compressible and fibrotic features, challenges existing OCE interpretations.

Purpose of the Study:

• To introduce a novel variant of OCE that maps the Euler angle, removing the uniaxial deformation assumption.
• To enhance micro-scale mechanical property mapping for improved breast cancer visualization and margin assessment.

Main Methods:

• Developed a hybrid 3-D displacement estimation combining phase-sensitive detection and complex cross-correlation.
• Enabled micro-scale 3-D displacement and strain tensor mapping.
• Introduced Euler angle imaging, representing the angle between principal compression and loading axis.

Main Results:

• Achieved 98.6% accuracy, 0.95° sensitivity, and 36 μm spatial resolution in Euler angle imaging of phantoms.
• Demonstrated Euler angle imaging's potential for breast cancer visualization.
• Euler angle mapping provided additional contrast for cancer identification compared to OCT and compression OCE.

Conclusions:

• Euler angle mapping in OCE overcomes limitations of uniaxial stress assumptions in heterogeneous tissues.
• This technique offers improved accuracy and contrast for intraoperative breast cancer margin assessment.
• Mapping the Euler angle may serve as a novel biomarker for breast cancer diagnosis.