Pilot study of use of laser fluorescence spectroscopy and optical tissue oximetry in the diagnosis and assessment of cicatricial lesions

Actuality. Hypertrophic and keloid scars are the outcomes of fibrosis associated with abnormally occurring accumulation of extracellular ma-trix, severe inflammation and changes in local tissue metabolism. The diagnostic approaches used today do not accurately assess the activi-ty, severity of the course and predict the outcome of cicatricial lesions, as they rely on subjective, non-quantitative and non-standardized methods. The use of non-invasive optical diagnostics, in particular laser fluorescence spectroscopy (LFS) and optical tissue oximetry (OTO), can be promising in this area. Objective. Pathogenetic substantiation of the use of LFS and OTO for differential diagnosis of various types of scar lesions. Material and methods. The study included 14 patients with postoperative scars in the facial region of head and neck. The optical parameters of skin were recorded by the LFS and OTO methods using the LAKK-M instrument (LLC NPP LAZMA). The fluorescence parameters of por-phyrins (λf=680—700 nm), collagen and elastin (λf=455 nm), as well as the characteristics of local blood flow, were evaluated. Comparison of samples was performed using Student’s t-test. Results. Patients with normotrophic scars showed a statistically significantly lower collagen fluorescence intensity — 0.5834 (95% CI 0.3644; 0.8024, p=0.0009) and a statistically significantly lower porphyrin fluorescence intensity — 0.6404 (95% CI) 0.4115; 0.8693, p=0.0268), as well as a higher oxygen consumption — 1.347 (95% CI 1.071; 1.623, p=0.0132) compared with similar parameters in patients with hyper-trophic / keloid cicatricial lesions — 1.628 (95% CI 0.8965; 2.360), 1.406 (95% CI 0.9349; 1.877), 0.7474 (95% CI 0.4973; 0.9975), respec-tively. Conclusion. The possibility of an objective, non-invasive study of changes in the connective tissue and a quantitative assessment of process-es of inflammation and hypoxia in the framework of development of skin fibrosis by the methods of LFS and OTO is demonstrated. The obtained patterns can be used to improve methods for assessing the course and diagnosis of various scars. © 2020, Media Sphera Publishing Group. All rights reserved