A non-contact, hand-held near-infrared optical scanner for spatial-temporal mapping of oxygenation changes in diabetic foot ulcers

Authors

Kevin Leiva, Florida International University Miami, FL ‧ Public ‧ 4-yearFollow

Document Type

Dissertation

Degree

Doctor of Philosophy (PhD)

Major/Program

Biomedical Engineering

First Advisor's Name

Anuradha Godavarty

First Advisor's Committee Title

Committee chair

Second Advisor's Name

Wei-Chiang Lin

Second Advisor's Committee Title

Committee member

Third Advisor's Name

Jessica Ramella-Roman

Third Advisor's Committee Title

Committee member

Fourth Advisor's Name

Jorge Riera

Fourth Advisor's Committee Title

Committee member

Fifth Advisor's Name

Wensong Wu

Fifth Advisor's Committee Title

Committee member

Keywords

Breath Hold, Diabetic Foot Ulcer, Spatio-temporal, Oxygenated Flow Index, Oxygenation Maps, Breath-Hold, Near-Infrared Spectroscopy, Tissue Oxygenation, Medical and Biological Imaging, Image Analysis, Oxygenated Flow, NIR imaging, diffuse optical imaging

Date of Defense

7-7-2022

Abstract

One in three people with diabetes will develop diabetic foot ulcers (DFUs) during their lifetime. The standard clinical approach to assess DFUs is via visual inspections of the wound for its size, color, temperature, smell, and epithelialization. Oxygen is vital for wounds to heals. Transcutaneous oximetry (TCOM) is the gold-standard clinical approach to measure the oxygen delivering capability of tissue, but only at discrete point locations around the wound. Various optical techniques have been developed to calculate tissue oxygenation maps of the wound and its surroundings. However, these techniques do not determine the capability of the tissues to deliver oxygen as in TCOM. My objective was to develop, validate, and test a near-infrared spectroscopic (NIRS) imaging system that can measure the oxygenation flow to the wounds. A near-infrared optical scanner (NIROS) capable of non-contact 2D spatial and temporal mapping of tissue oxygenation changes was developed. Phantom and in-vivo validation studies demonstrated that NIROS was capable of mapping time-varying tissue oxygenation changes with 88% and 95% correlation, respectively, to existing standard approaches. A breath-hold paradigm was developed as a stimulus to induce tissue oxygenation changes via vascular tone changes, like TCOM, to assess oxygenated flow to the foot. Breath-hold induced tissue oxygenation changes were synchronous across the dorsal and plantar sides of the feet in control subjects, upon using the optimized 20-sec breath-hold and 20-sec post breath-hold paradigm. Ten DFU subjects were imaged in response to a breath-hold paradigm using NIROS in an IRB-approved study. An oxygenated flow index (OFI) was developed to differentiate non-healing DFUs from healing DFUs. Cases with OFI

Identifier

FIDC010993

ORCID

https://orcid.org/0000-0001-7521-6015

Previously Published In

Leiva, Kevin, et al. "Breath-hold paradigm to assess variations in oxygen flow in diabetic foot ulcers using a noncontact near-infrared optical scanner." Advances in Wound Care 8.8 (2019): 386-402.

Recommended Citation

Leiva, Kevin, "A non-contact, hand-held near-infrared optical scanner for spatial-temporal mapping of oxygenation changes in diabetic foot ulcers" (2022). FIU Electronic Theses and Dissertations. 5233.
https://digitalcommons.fiu.edu/etd/5233