Use of FLIR ONE Smartphone Thermography in Burn Wound Assessment

Forward-looking infrared (FLIR) thermography technology uses a handheld camera that measures skin infrared emissivity, captures photographs, and can be analyzed through specialized software. Forward-looking infrared images can be used to analyze and correlate burn wound temperature with burn depth, burn progression, and the number of days needed for healing. FLIR ONE is a miniature, smartphone-compatible thermal imaging camera that has been used to assess inflammation in diabetic foot ulcers, as well as locating perforators in flap surgery. However, FLIR ONE's reliability in burn wound assessment has not been evaluated. This case series investigates the accuracy of FLIR ONE in comparison with the widely used indocyanine green (ICG) angiography in assessing burn wounds.

Five acute third-degree burn wounds were assessed using ICG angiography and FLIR ONE imaging (infrared thermography) to determine burn extent before surgical intervention. Patients were taken to the operating room within 48 hours of presentation; FLIR ONE images were captured approximately 35 to 45 cm above the wound surface. Margins of unsalvageable tissue as determined by ICG and FLIR ONE were marked and compared.

The area of unsalvageable tissue as determined by FLIR ONE closely corresponded to the area determined by ICG. FLIR ONE overestimated unsalvageable tissue margins by approximately 1 to 2 cm. The area estimated by ICG consistently overlapped with more than 90% of the area estimated by FLIR ONE.

There is a strong correlation between FLIR ONE and ICG when assessing salvageable tissue in third-degree burn wounds. FLIR ONE maximizes the convenience and cost-effectiveness of infrared thermography technology but may overestimate unsalvageable tissue area. FLIR ONE is promising as an adjunct to current imaging modalities such as ICG but requires further study for comparison.