Event Title

Comparison Study: Effect of breath-hold paradigm on oxygenation flow in normal and chronic diabetic foot ulcer subjects

Presenter Information

Bridgette Meyer

Department

Biomedical Engineering

Faculty Advisor

Anuradha Godavarty

Start Date

1-10-2020 9:00 AM

End Date

1-10-2020 10:00 AM

Abstract

It is estimated that of the world's population, 415 million people are diagnosed with diabetes, the United States alone contributing 30.3 million. Of this population, approximately 25% are afflicted with diabetic foot ulcers (DFUs), which in the most chronic cases require specialized wound care and possibly limb amputation. Past studies using a non-contact, hand-held Near Infrared Optical Scanner (NIROS), developed in the Optical Imaging Lab (OIL) at FIU have detected a decrease in wound-to-background contrast in terms of tissue oxygenation. More recently, studies using NIROS have expanded into dynamic imaging, capturing changes in oxygenation with respect to time that can provide more physiological information that can attribute to wound healing. Dynamic imaging uses an external stimulus to alter the oxygenation flow to the region of interest. A controlled study of three normal subjects was acquired in response to a 20 seconds breath-hold stimulus and compared to a previous study from a chronic mixed-arterial diabetic foot ulcer subject imaged over 50 weeks. In conjunction with the breath-hold stimulus, hemoglobin parameters in terms of oxy-, deoxy, total hemoglobin and oxygen saturation were calculated using the modified Beer-Lambert's Law. Changes in tissue oxygenation were assessed from these parameters to identify changes in oxygenated flow within the posterior calf and ankle region. The Pearson's Correlation Coefficient (PCC) was calculated to identify any correlation in the changes in the flow within the tissue of both subject groups. Correlations maps in terms of oxygen saturation showed that in the DFU subject, the PCC displayed a range of values showing strong negative and positive correlation across the region of interest. As the course of treatment progressed, the concentration of positive correlation in the DFU subject increased post-revascularization procedure. In the control subjects, however, it was observed that across three subjects the maps were identical. All subjects had positive correlations on the equivalent of the location of the foot that appeared to be a homogenous mixture of correlation coefficients. One normal subject was imaged thrice also producing identical uniform results, showing the repeatability of the measurements. The study of control subjects in conjunction with the DFU subject provided results showing the ability to reproduce identical trends in normal subjects and allowed for a clear distinction between the correlations of control versus DFU subjects.

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Oct 1st, 9:00 AM Oct 1st, 10:00 AM

Comparison Study: Effect of breath-hold paradigm on oxygenation flow in normal and chronic diabetic foot ulcer subjects

It is estimated that of the world's population, 415 million people are diagnosed with diabetes, the United States alone contributing 30.3 million. Of this population, approximately 25% are afflicted with diabetic foot ulcers (DFUs), which in the most chronic cases require specialized wound care and possibly limb amputation. Past studies using a non-contact, hand-held Near Infrared Optical Scanner (NIROS), developed in the Optical Imaging Lab (OIL) at FIU have detected a decrease in wound-to-background contrast in terms of tissue oxygenation. More recently, studies using NIROS have expanded into dynamic imaging, capturing changes in oxygenation with respect to time that can provide more physiological information that can attribute to wound healing. Dynamic imaging uses an external stimulus to alter the oxygenation flow to the region of interest. A controlled study of three normal subjects was acquired in response to a 20 seconds breath-hold stimulus and compared to a previous study from a chronic mixed-arterial diabetic foot ulcer subject imaged over 50 weeks. In conjunction with the breath-hold stimulus, hemoglobin parameters in terms of oxy-, deoxy, total hemoglobin and oxygen saturation were calculated using the modified Beer-Lambert's Law. Changes in tissue oxygenation were assessed from these parameters to identify changes in oxygenated flow within the posterior calf and ankle region. The Pearson's Correlation Coefficient (PCC) was calculated to identify any correlation in the changes in the flow within the tissue of both subject groups. Correlations maps in terms of oxygen saturation showed that in the DFU subject, the PCC displayed a range of values showing strong negative and positive correlation across the region of interest. As the course of treatment progressed, the concentration of positive correlation in the DFU subject increased post-revascularization procedure. In the control subjects, however, it was observed that across three subjects the maps were identical. All subjects had positive correlations on the equivalent of the location of the foot that appeared to be a homogenous mixture of correlation coefficients. One normal subject was imaged thrice also producing identical uniform results, showing the repeatability of the measurements. The study of control subjects in conjunction with the DFU subject provided results showing the ability to reproduce identical trends in normal subjects and allowed for a clear distinction between the correlations of control versus DFU subjects.