About 6.5 million people in the United States suffer from chronic wounds, which often take months to heal and are often harbored by bacteria. If not removed promptly, these bacteria can to serious infection and even require amputation. The risk is particularly significant for people with diabetes, with one in three patients developing a diabetic foot ulcer, and about 20% of such patients eventually have to undergo amputation, according to the American Diabetes Association.

During traditional wound debridement, doctors try to remove bacteria, but due to the limitations of the naked eye, some bacteria may be missed. In a study published in the journal Advances in Wound Care, researchers from the Keck School of Medicine of USC showed that autofluorescence (AF) imaging technology can more effectively detect and identify bacteria in wounds.

AF imaging technology uses ultraviolet light through a handheld device to "light up" bacteria that are invisible to the naked eye, causing them to fluoresce in different colors, thereby helping doctors quickly determine the number and type of bacteria in the wound.

"We anticipate that this technology will improve surgeons' precision in removing bacteria from wounds, thereby improving outcomes, especially for patients with diabetic foot wounds," said David G. Armstrong, MD, a podiatrist and limb preservation specialist at Keck Medicine and senior author of the study.

The study, a meta-analysis of 25 studies, found that AF imaging can identify bacteria in about 90% of patient wounds that are often overlooked during traditional clinical assessments.

In traditional methods, doctors need to send tissue samples to the laboratory for bacterial testing after debridement, which may take several days and increase the risk of infection. AF imaging technology allows doctors to make medical decisions immediately during the debridement process without waiting for laboratory results.

In addition, this technology can help patients avoid unnecessary use of antibiotics, extend wound care time, and reduce the risk of antibiotic resistance.

Keck Medicine has successfully used AF imaging to treat several patients with chronic wounds, including diabetic foot ulcers. Looking ahead, Dr. Armstrong hopes to see AF imaging become the new standard of wound care.