We demonstrate the use of phase-stabilized swept-source optical coherence tomography to assess the propagation of low-amplitude (micron-level) waves induced by a focused air-pulse system in tissue-mimicking phantoms, a contact lens, a silicone eye model, and the mouse cornea in vivo. The results show that the wave velocity can be quantified from the analysis of wave propagation, thereby enabling the estimation of the sample elasticity using the model of surface wave propagation for the tissue-mimicking phantoms. This noninvasive, noncontact measurement technique involves low-force methods of tissue excitation that can be potentially used to assess the biomechanical properties of ocular and other ...
Kirill Larin, Ph.D.
Associate Professor
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We present a three-dimensional (3-D) computational method to detect soft tissue sarcomas with the goal of automatic surgical margin assessment based on optical coherence tomography (OCT) images. Three parameters are investigated and quantified from OCT images as the indicators for the tissue diagnosis including the signal attenuation (A-line slope), the standard deviation of the signal fluctuations (speckles), and the exponential decay coefficient of its spatial frequency spectrum. The detection of soft tissue sarcomas relies on the combination of these three parameters, which are related to the optical attenuation characteristics and the structural features of the tissue. Pilot experiments were performed ...
Accurate non-invasive assessment of tissue elasticity in vivo is required for early diagnostics of many tissue abnormalities. We have developed a focused air-pulse system that produces a low-pressure and short-duration air stream, which can be used to excite transient surface waves (SWs) in soft tissues. System characteristics were studied using a high-resolution analog pressure transducer to describe the excitation pressure. Results indicate that the excitation pressure provided by the air-pulse system can be easily controlled by the air source pressure, the angle of delivery, and the distance between the tissue surface and the port of the air-pulse system. Furthermore, we ...
Kirill V. Larin is Assistant Professor of Biomedical Engineering at the University of Houston, Houston, TX. His research interests focuses on development and application of OCT for noninvasive and nondestructive imaging and diagnostics of tissues and cells. Larin has authored more than 40 peer-reviewed journal publications and chapters in two textbooks on Biomedical Optics. He is recipient of Boris Yeltsin Presidential Award, Wallace Coulter Young Investigator Translation Award, Office of Naval Research Young Investigator Award, and Outstanding Young Investigator Award from the Houston Society for Engineers in Medicine and Biology.
We are using OCT to image mouse and rat embryos, looking at video taken about seven days after conception, out of a 20-day typical mammalian pregnancy...this way, we are able to capture video of the embryonic heart before it begins beating, and a day later we can see the heart beginning to form in the shape of a tube and see whether or not the chambers are contracting. Then, we begin to see blood distribution and the heart rate.In The Embryonic Heart: Imaging Life as it Happens - University of Houston Professor Captures Video of Heart Before it Begins to Beat (Video Snippet)
Our primary objective is to develop noninvasive, early detection methods to diagnose various diseases.In U. Houston professor expands Optics research