Contrast Enhancement of Laser Speckle Contrast Image in Deep Vasculature by Reduction of Tissue Scattering

Various methods have been proposed for enhancing the contrast of laser speckle contrast image (LSCI) in subcutaneous blood flow measurements. However, the LSCI still suffers from low image contrast due to tissue turbidity. Herein, a physicochemical tissue optical clearing (PCTOC) method was employed to enhance the contrast of LSCI. Ex vivo and in vivo experiments were performed with porcine skin samples and male ICR mice, respectively. The ex vivo LSCIs were obtained before and 90 min after the application of the PCTOC and in vivo LSCIs were obtained for 60 min after the application of the PCTOC. In order to obtain the skin recovery images, saline was applied for 30 min after the application of the PCTOC was completed. The visible appearance of the tubing under ex vivo samples and the in vivo vasculature gradually enhanced over time. The LSCI increased as a function of time after the application of the PCTOC in both ex vivo and in vivo experiments, and properly recovered to initial conditions after the application of saline in the in vivo experiment. The LSCI combined with the PCTOC was greatly enhanced even in deep vasculature. It is expected that similar results will be obtained in in vivo human studies.

[1]  Andrew K. Dunn,et al.  Efficient Processing of Laser Speckle Contrast Images , 2008, IEEE Transactions on Medical Imaging.

[2]  Bernard Choi,et al.  Impact of velocity distribution assumption on simplified laser speckle imaging equation. , 2008, Optics express.

[3]  Anna Devor,et al.  Determination of optimal exposure time for imaging of blood flow changes with laser speckle contrast imaging. , 2005, Applied optics.

[4]  Kevin R. Forrester,et al.  A laser speckle imaging technique for measuring tissue perfusion , 2004, IEEE Transactions on Biomedical Engineering.

[5]  Donald D Duncan,et al.  Detrimental effects of speckle-pixel size matching in laser speckle contrast imaging. , 2008, Optics letters.

[6]  Q. Luo,et al.  Modified laser speckle imaging method with improved spatial resolution. , 2003, Journal of biomedical optics.

[7]  Shaoqun Zeng,et al.  Hyperosmotic chemical agent's effect on in vivo cerebral blood flow revealed by laser speckle. , 2004, Applied optics.

[8]  Wiley Interscience,et al.  Endoscopic laser imaging of tissue perfusion: New instrumentation and technique , 2003, Lasers in surgery and medicine.

[9]  N. Thakor,et al.  Contrast-enhanced imaging of cerebral vasculature with laser speckle. , 2007, Applied optics.

[10]  J. Tulip,et al.  Endoscopic laser speckle imaging of tissue blood flow: Applications in the human knee , 2006, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[11]  Bernard Choi,et al.  Linear response range characterization and in vivo application of laser speckle imaging of blood flow dynamics. , 2006, Journal of biomedical optics.

[12]  J. Tulip,et al.  Comparison of laser speckle and laser Doppler perfusion imaging: Measurement in human skin and rabbit articular tissue , 2002, Medical and Biological Engineering and Computing.

[13]  Bernard Choi,et al.  Enhancement of optical skin clearing efficacy using a microneedle roller. , 2008, Journal of biomedical optics.

[14]  F Scheffold,et al.  Laser speckle imaging with an active noise reduction scheme. , 2005, Optics express.

[15]  Shaoqun Zeng,et al.  Efficient characterization of regional mesenteric blood flow by use of laser speckle imaging. , 2003, Applied optics.

[16]  Gracie Vargas,et al.  Morphological Changes in Blood Vessels Produced by Hyperosmotic Agents and Measured by Optical Coherence Tomography¶ , 2003, Photochemistry and photobiology.