Diagnosis of Burn Depth Using Laser-induced Indocyanine Green Fluorescence: a Preliminary Clinical Trial

Clinical assessment of burn depth is frequently inaccurate. In order to effectively plan the treatment of burn wounds, an accurate diagnosis of burn depth is desirable. A new method for evaluating the depth of burns by imaging the blood flow through the burned tissue using fluorescence from intravenously injected indocyanine green (ICG) dye illuminated with a 785-nm, near-infrared diode laser array was evaluated. Nine patients and 15 individual burn sites were studied. Five sites were classified by the ICG study as superficial second degree, four were deep-dermal second degree, and six were third degree. Etiology of the injuries included flame, contact burns, and scalds. The date postburn of the study ranged from 1 to 11 days. In all cases, the relative fluorescence levels (e.g. superficial second-degree burns yielded relatively bright fluorescence, third-degree burns appeared much darker than surrounding normal skin) were found to correlate well with actual burn depth as determined by histologic examination of biopsies and intraoperative clinical assessment.