ABSTRACT
Mechanical compression of tissues is a potential contrast enhancement approach based on the possibility of controlling tissue optical properties through the redistribution and close packing of scatterers. The close packing of scatterers accompanied by extracellular fluid redistribution provides an optical clearing effect, while the different elastic properties of tissue layers result in layer contrasting.
This chapter discusses the effects of mechanical compression on images obtained with optical coherence tomography (OCT). Contact OCT probes conjugated with customized devices allow for controlling the level of compression in the inspected tissue. The chapter overviews the effects of mechanical compression on the optical properties of biotissues, the variations induced by compression observed in OCT inspection of biotissues ex vivo and in vivo, and ways to increase the diagnostic value of OCT with compression.
Pathological processes in tissues induce morphologic changes, which, in turn, affect tissue layer elasticity, which can be detected by a combination of OCT and controlled mechanical compression. The chapter overviews ex vivo studies of the effect of mechanical compression on human rectum, in vivo studies of the effect of mechanical compression on human skin, and the combined effect of compression and temperature. The mechanisms of optical property variation in tissues under compression are discussed.
