New applications of biomedical imaging via autofluorescence tools can visually “light up” bacteria, allowing clinicians to debride — or remove non-viable tissue in wounds — and prevent infection, according to a research study published by Keck Medicine of USC in “Advances in Wound Care.”

Some health conditions, including diabetes, can increase the risk of developing chronic wounds, also known as non-healing wounds. About half of diabetic foot ulcers become infected — and an estimated 20% can require amputations.

Chronic wounds, which occur when tissue does not heal within an expected time frame, can become susceptible to bacterial growth and infections. Wound infections can require treatment with antibiotics or, in critical cases, amputation.

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Certain health conditions can affect healing processes due to underlying disease pathophysiology. Diabetic neuropathy — damage to the nerves — can alter sensations of pain and predispose patients to diabetic foot ulcers and severe infections.

Infections, while sometimes visible by signs of inflammation or blistering skin, are not indicative of the extent of bacterial load in wounds. Current clinical diagnostic methods, such as sampling and assessing bacteria, can assist in infection treatment. Detecting bacteria more accurately and efficiently allows clinicians to remove necrotic tissue and promote healing of a wound.

The study evaluated the use of autofluorescence imaging, which can be used to make bacteria “glow” by transillumination.

“If we see a lot of bacteria in an area, then that might be someone that might be at risk for getting a wound,” said Dr. David Armstrong, a podiatric surgeon and limb preservation specialist with Keck Medicine of USC, who led the research study. “We can debride that away gently and efficiently and maybe stop the infection before it starts.”

Clinicians assessing the extent of infection may be able to use the AF imaging tool to visualize the location of bacteria present in non-healing wounds. The technology can be affixed to a  handheld or to a head-mounted display, Armstrong said.

AF imaging is used in other biomedical applications to assist in the diagnosis of retinal disease by detecting the presence of fluorophores — or molecules that light up under microscope imaging — in the eye.

In infection prevention, the innovation is promising: Nearly 90% of bacteria present in chronic wounds display AF properties. Clinical providers can use AF to make bacteria glow red or cyan, which allows for more efficient debriding of wounds.

“Since technology can identify indicators of things that could get worse, [it] could help prevent things before the condition exacerbates,” said Shreeya Chand, a freshman majoring in computer science.

Roshni Lulla, a graduate student studying psychology, said the health advancements could improve early diagnostics and benefit health outcomes.

“Technology has a huge impact, especially [with] the rise of [artificial intelligence] recently, you can detect things a lot quicker [and] can help diagnose,” Lulla said. “Especially [for] someone who has diabetes or any other comorbidities, they have so many other things that they have to think about [and] there’s additional risk of having infections.”

A new diabetes-associated wound occurs every second globally, Armstrong said.

Other underlying health issues and conditions — including poor circulation, weakened immune system functioning and chronic kidney disease — can also increase the risk of non-healing wounds, according to other studies.

Armstrong’s study, a literature review of 25 studies, considers the application of preexisting biomedical technology to new tools — and the impact in advancing diagnostics and prevention of chronic wounds, severe infections and amputations.

Armstrong hopes the AF imaging will improve health outcomes for patients.

“This may be one of those kinds of instruments that might help us better measure what we manage,” Armstrong said. “If we can identify these problems, like infections, and we can get in front of them by being able to identify these risk factors, then maybe we can make a difference.”

Editor’s Note: A previous version of this article misrepresented Dr. David Armstrong’s affiliation to the University. He works for Keck Medicine of USC, not Keck School of Medicine of USC. The article was updated Sept. 15 at 4 p.m. to reflect this change.

Editor’s Note: A previous version of this article stated Dr. David Armstrong worked for Keck Medicine of USC and not Keck School of Medicine of USC. He works at both entities, but his study was a part of his clinical work done under Keck Medicine of USC. The article was updated Sept. 23 at 3 p.m. to reflect this change.