The absorption of nanosecond laser pulses induces rapid thermo-elastic deformation in tissue. A sub-micrometer scale displacement occurs within a few microseconds after the pulse arrival. In this Letter, we investigate the laser-induced thermo-elastic deformation using a 1.5 MHz phase-sensitive optical coherence tomography (OCT) system. A displacement image can be reconstructed, which enables a new modality of phase-sensitive OCT, called thermo-elastic OCT. An analysis of the results shows that the optical absorption is a dominating factor for the displacement. Thermo-elastic OCT is capable of visualizing inclusions that do not appear on the structural OCT image, providing additional tissue type information.,
Optics Letters
Erasmus MC: University Medical Center Rotterdam

Wang, T., Pfeiffer, A., Wu, M., Wieser, W., Amenta, G. (Gaetano), Draxinger, W. (Wolfgang), … van Soest, G. (2017). Thermo-elastic optical coherence tomography. Optics Letters, 42(17), 3466–3469. doi:10.1364/OL.42.003466