This Exploratory/Developmental Research (R21) application proposes to study the phenomenon of turbidity suppression optical phase conjugation (TS-OPC) and explore its uses for biomedical applications. TS-OPC - a biophotonic phenomenon recently observed by my group, is based on the use of optical phase conjugation to suppress tissue turbidity. Unlike absorption, elastic optical scattering is a time reversible process. As such, a time reversed copy of the scattered field should be able to retrace its trajectory through the scattering medium and recover the original light field. Our initial experiments revealed that this phenomenon is surprisingly robust - we were able to observe the phenomenon with a chicken tissue section of thickness 5mm and a wavelength of 532 nm. Our initial investigations also point to the potential utility of the method for several applications: optical powering of miniature sub-dermal implants, improving photodynamic therapy procedures, tissue absorption/scattering interrogation, etc. The focus of the proposed research is to attain a more complete understanding of the technique's working principle, streamline its implementation in reflection mode and begin initial investigations into its use for enhanced and targeted light delivery into tissues for photodynamic applications.
The specific aims of the proposed research are: 1. Develop a quick, efficient and simple reflection mode TS-OPC system. 2. Experimentally determine the limits of the reflection mode TS-OPC method. 3. Develop a theoretical framework for understanding the TS-OPC method. 4. Begin initial investigations into the use of TS-OPC for enhanced and targeted light delivery into tissues - useful for photodynamics therapy (PDT). Narrative for Optical phase conjugation project

Public Health Relevance

The phenomenon of turbidity suppression via optical phase conjugation can potentially be adapted for clinical diagnosis and therapeutics. The funding of the proposed research will allow us to better understand this newly discovered phenomenon and allow us to begin exploring one of its more promising applications - the enhancement of light delivery during photodynamic therapy procedures.

Agency
National Institute of Health (NIH)
Institute
National Institute of Biomedical Imaging and Bioengineering (NIBIB)
Type
Exploratory/Developmental Grants (R21)
Project #
3R21EB008866-02S1
Application #
7905427
Study Section
Special Emphasis Panel (ZRG1-SBIB-J (90))
Program Officer
Zhang, Yantian
Project Start
2008-07-01
Project End
2010-08-31
Budget Start
2009-09-01
Budget End
2010-08-31
Support Year
2
Fiscal Year
2009
Total Cost
$40,125
Indirect Cost
Name
California Institute of Technology
Department
Engineering (All Types)
Type
Schools of Engineering
DUNS #
009584210
City
Pasadena
State
CA
Country
United States
Zip Code
91125
Cui, Meng; McDowell, Emily J; Yang, Changhuei (2010) An in vivo study of turbidity suppression by optical phase conjugation (TSOPC) on rabbit ear. Opt Express 18:25-30
Cui, Meng; Yang, Changhuei (2010) Implementation of a digital optical phase conjugation system and its application to study the robustness of turbidity suppression by phase conjugation. Opt Express 18:3444-55
McDowell, Emily J; Cui, Meng; Vellekoop, Ivo M et al. (2010) Turbidity suppression from the ballistic to the diffusive regime in biological tissues using optical phase conjugation. J Biomed Opt 15:025004
Zheng, Guoan; Heng, Xin; Yang, Changhuei (2009) A Phase-Conjugate-Mirror Inspired Approach for Building Cloaking Structures with Left-handed Materials. New J Phys 11:33010
Yaqoob, Zahid; Psaltis, Demetri; Feld, Michael S et al. (2008) OPTICAL PHASE CONJUGATION FOR TURBIDITY SUPPRESSION IN BIOLOGICAL SAMPLES. Nat Photonics 2:110-115