Tissue Damage Characterization Using Non-invasive Optical Modalities
Monday, March 7, 2016
9:00 AM-11:00 AM
BIOMED PhD Defense
Title:
Tissue Damage Characterization Using Non-invasive Optical Modalities
Speaker:
David Diaz, PhD candidate, School of Biomedical Engineering, Science and Health Systems
Advisors:
Peter Lewin, PhD, and Leonid Zubkov, PhD, School of Biomedical Engineering, Science and Health Systems
Abstract:
The ability to determine the degree of cutaneous and subcutaneous tissue damage is essential for proper wound assessment and a significant factor for determining patient treatment and outcomes. Accurate characterization of tissue damage is critical for a number of medical applications including severity assessment of subcutaneous ulcers and depth assessment of cutaneous wounds.
The main objective of this research was to develop a non-invasive method for identifying the extent of tissue damage underneath intact skin that is not apparent upon visual examination. This work investigated the relationship between tissue optical properties, blood flow, and tissue viability by testing the hypotheses that (a) changes in tissue oxygenation and/or microcirculatory blood flow measurable by Diffuse Near Infrared Spectroscopy (DNIRS) and Diffuse Correlation Spectroscopy (DCS) differ between healthy and damaged tissue and (b) the magnitude of those changes differs for different degrees of tissue damage. This was accomplished by developing and validating a procedure for measuring microcirculatory blood flow and tissue oxygenation dynamics at multiple depths (up to 1 centimeter) using non-invasive DCS and DNIRS technologies.
A human study was conducted and optical data were collected from healthy subjects and subjects at risk of developing pressure ulcers. Blood flow index values from the sacral region were compared within subject groups and statistical differences were observed between patients who developed pressure ulcers and those who did not.
Overall, this work presents a novel non-invasive method of pressure ulcer assessment and provides an improvement over current assessment methods. The results suggest the system may potentially predict whether non-blanchable redness will develop into an advanced pressure ulcer within four weeks from initial observation. This is the first time these optical modalities have been used for the quantitative and objective assessment of pressure ulceration.
Contact Information
Ken Barbee
215-895-1335
barbee@drexel.edu