Rapid noncontact laser speckle imaging for perfusion-based differentiation of wound necrosis

Traditional wound assessment relies on subjective visual inspection, which may miss early microvascular changes. In this study, laser speckle contrast imaging (LSCI) was used to differentiate necrotic from nonnecrotic wounds using quantitative perfusion under a shortened protocol. Forty wound patients (20 acute, 15 chronic, and 5 necrotic) and 20 participants without wound lesions were included. Within-subject normalized perfusion (percent change relative to adjacent healthy skin) served as the predictor. Significant differences were observed among wound types (ε ² = 0.23-0.40, moderate-to-large effects). ROC analysis yielded an AUC of 0.88 (95% CI: 0.66-1.00; cutoff ≤-22.6%; accuracy 0.92; sensitivity 0.80; specificity 0.94; negative predictive value (NPV) 0.97). The 10-s protocol performed comparably to the 60-s acquisition (AUC = 0.84; accuracy = 0.87; r = 0.97; intraclass correlation coefficient (ICC) = 0.97). LSCI may offer a noncontact, rapid approach for perfusion-based necrosis differentiation, although the small necrotic sample (n = 5) necessitates validation in larger cohorts.