Prospective comparative evaluation study of Laser Doppler Imaging and thermal imaging in the assessment of burn depth

Abstract

Introduction: The accurate assessment of burn depth is challenging but crucial for surgical excision and tissue preservation. Laser Doppler Imaging (LDI) has gained increasing acceptance as a tool to aid depth assessment but its adoption is hampered by high costs, long scan times and limited portability. Thermal imaging is touted as a suitable alternative however few comparison studies have been done.

Methods: Sixteen burn patients with 52 regions of interests were analysed. Burn depth was determined using four methods LDI, thermal imaging, photographic and real-time clinical evaluation at day 1 and day 3. LDI flux and Delta T values were used for the prediction of outcomes (wound closure in <21 days). Photographic clinical evaluation of burn depth was performed by 4 blinded burn surgeons.

Results: Accuracy of assessment methods were greater on post burn day 3 compared to day 0. Accuracies of LDI on post burn day 0 and 3 were 80.8% and 92.3% compared to 55.8% and 71.2% for thermal imaging and 62.5% and 71.6% for photographic clinical assessment. Real-time clinical examination had an accuracy of 88.5%. Thermal imaging scan times were significantly faster compared to LDI.

Discussion: LDI outperforms thermal imaging in terms of diagnostic accuracy of burn depth likely due to the susceptibility of thermal imaging to environmental factors.

Keywords: Burn depth; Clinical assessment; Laser Doppler Imaging; Thermal imaging.