Optical Elastography : Optical Techniques for Assessing Cell and Tissue Biomechanics

Optical elastography is a set of imaging techniques that use light to measure the mechanical properties of tissues and cells, which are crucial in understanding development and disease, especially cancer. Unlike ultrasound or MRI-based elastography, optical methods offer higher spatial resolution and sensitivity and can be miniaturized for clinical use. The process involves detecting tissue deformation—either externally applied or naturally occurring—and using mechanical models to map this to properties like Young’s or shear modulus. The book outlines key techniques, including optical coherence elastography (OCE), which mirrors ultrasound methods, and laser speckle-based elastography, which uses laser patterns to track tissue motion. Brillouin microscopy, a high-resolution method based on confocal microscopy, measures tissue stiffness via phonon interactions. Photoacoustic elastography (PAE) is also emerging as a promising tool. Other methods include traction force microscopy, which maps cellular forces, and related techniques like optical trapping and polarization microscopy. The book concludes with a look at multimodal approaches and future applications, highlighting the growing role of optical elastography in biomedical imaging and diagnostics.