Joris van Dongen

190 Chapter 8 tSVF suppresses scar formation up to six months postoperative Injection of tSVF improved postoperative scar appearance significantly as compared to a placebo injection as evaluated at six months postoperative (Fig. 1). However, this significant difference in scar appearance between the tSVF and placebo group disappeared after twelve months. The average total score of the patient part of the POSAS questionnaire was 21 ± 15.0 versus 24.5 ± 13.0 for respectively tSVF and the placebo group after six months (p<0.05, fig. 2). A sub-analysis of scar characteristics revealed a difference in color, thickness, irregularity (p<0.05) as well as the overall opinion (p<0.01). The average total score of the observer part of the POSAS questionnaire was 18.8 ± 11.3 versus 23.6 ± 11.2 for respectively tSVF and the placebo group after six months (p<0.01, fig. 2). A sub-analysis of scar characteristics revealed a difference in vascularity, relief (p<0.05) as well as thickness, pliability, surface and overall opinion (p<0.01, fig. 2). 3.3 Photographic evaluation Post-operative scar appearance between tSVF treated and placebo treated wound areas did not differ irrespective of the moment of assessment (Fig. 3). The intra-observer agreement was fair (0.21 - 0.40) for four observers, while the intra-observer agreement was poor (<0.2) for five observers (Table 2). All inter-observer agreements within each observer group were poor. The low intra- and interobserver agreements highlight the subjective nature of a photographic evaluation of postoperative scar appearance.