Non-invasive objective assessment of diabetic foot ulcer healing with blood perfusion and tissue oxygenation

The high prevalence of the world's population diagnosed with diabetes mellitus, with a significant number suffering from diabetic foot ulcer (DFU), has always been a global concern. Although modern medical technologies are available to assist medical physician in wound diagnosis, the practicability of these techniques have yet to be critically assessed. Only a limited number of biomedical researches have examined the correlation between blood flow and tissue oxygenation in diabetic wounds. This thesis is a pioneering work that aims to develop a reliable diagnostic tool to address the tremendous need for coordinated and efficient DFU management via prediction of relative blood perfusion (τ) and transcutaneous oxygen saturation (StO2). The laser speckle integrated multispectral imaging system is an optical, non�invasive system that is able to provide quantitative and visual information of blood perfusion and tissue oxygen in diabetic ulcer. The estimation of blood perfusion is based on speckle contrast analysis of blood flow whereas the estimation of StO2 parameter is by means of fitting the Extended Modified Lambert Beer model to the collected attenuation data. This system incorporates the use of a 650 nm low power laser diode for in-vivo assessment of blood perfusion and wavelength in the visible range of 530 570 − nm to predict tissue oxygenation using priori information of hemoglobin's coefficients. A study was conducted on DFU patients recruited from Hospital Sultanah Nora Ismail. The results from this research revealed a slightly higher mean blood perfusion and tissue oxygen level in positive healing wounds than in impaired healing wounds, despite data indicating no statistical significance between these two groups ( ρ = 0.909 and ρ = 0.512 for τ and StO2 data, respectively). This research concludes that a mean blood perfusion index of 3 1.5 ( 10 ) × and percent StO2 of at least 70 % are vital during the proliferative phase to ensure progressive healing. The strategies explored in this work can provide quantitative information of changes in blood perfusion with tissue revascularization to evaluate the outcomes of skin grafting procedures in positive and impaired healing diabetic wounds.

Name dc:type.qualificationname

phd

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

Universiti Tun Hussein Onn Malaysia

Year dc:date.issued

2020

Author dc:creator

• Philimon, Sheena Punai

• RC Internal medicine
• QA71-90 Instruments and machines

Language dc:language

en