Talk abstracts

Talk on Thursday 11:50-12:05pm submitted by Jiwei Huang

Multispectral imaging of cutaneous tissue oxygen

Jiwei Huang (Biophysics Program, Department of Biomedical Engineering, Ohio State University), Evert Qin (Biomedical Engineering), Dr. Jeff Xu (Biomedical Engineering), Dr. Ronald Xu (Biomedical Engineering)

Abstract:
Background: Oxygen level (i.e. oxygen saturation, StO2) is considered as a predictor of tissue viability in the process of wound healing. Measuring cutaneous tissue oxygen levels during wound healing is clinically significant because it will help clinicians to make better informed decision in managing wound debridement. However, none of the currently-available method can provide non-contact cutaneous tissue oxygen imaging. Thus, the purpose of this study is to explore a new multispectral imaging algorithm, and based on which develop an imaging system for cutaneous tissue oxygen saturation measurement.

Research method: The multispectral algorithm is a wide-gap second derivative algorithm in which cutaneous tissue oxygen saturation can be calculated from the tissue reflectance images of four wavelengths: 530, 550, 570, 590nm. This algorithm can reduce the measurement bias caused by different skin color and tissue scattering. The imaging system consisted of a high-resolution CCD camera, a liquid crystal tunable filter, and a broad-band light source. A user interface was programmed using Labview for simultaneous control of all components and data acquisition.

Result: We first tested the multispectral algorithm and imaging system on a tissue-simulating phantom. The oxy-hemoglobin dissociation curve of the phantoms was measured. We then conducted a pilot study on a human subject. The multispectral system was used to image the oxygen saturation of the arm tissue of the subject during a postocclusive reactive hyperemia (PORH) test. The reconstructed StO2 map was consistent with the oxygen measurements of two other oximeters (ISS and TCM), indicating that the multispectral imaging system is feasible for cutaneous tissue oxygen saturation measurement.

Conclusion: We developed multispectral imaging algorithm and system for cutaneous tissue oxygen measurement. A pilot study on a human subject was conducted and the oxygen saturation of his arm tissue was imaged during a PORH test.

Keywords: multispectral imaging, cutaneous tissue oxygen