Intralesional treatments for hypertrophic scars: comparison among corticosteroid, 5-fluorouracil and botulinum toxin in rabbit ear hypertrophic scar model.

OBJECTIVE: Different treatment modalities have been used either alone, or in combination to achieve an optimum improvement for hypertrophic scars. Intralesional injections of corticosteroids and 5-fluorouracil are among the most commonly used treatments. Recently, botulinum toxin is proposed as a new treatment option. In this study, it is aimed to compare the efficacies of intralesional triamcinolone acetonide, 5-fluorouracil and botulinum toxin-A for hypertrophic scars. In order to minimize the variables affecting scar formation, standardized wounds in rabbit ear hypertrophic scar model was used. MATERIALS AND METHODS: Four surgical wounds were created on both ears of eight rabbits. Injections to be compared (triamcinolone acetonide, 5-fluorouracil, botulinum toxin-A and control) are administered intralesionally to established scars on day 30. Scars were harvested on day 60 for morphometric analysis including hypertrophic index, fibroblast density, and relative collagen density. RESULTS: Triamcinolone acetonide and 5-fluorouracil injections decreased hypertrophic indexes significantly compared to botulinum toxin-A and control group. However, only 5-fluorouracil was effective to reduce fibroblast counts significantly. No statistically significant differences were found between the treatment groups in terms of collagen index. CONCLUSIONS: According to the results of our study, triamcinolone acetonide and 5-fluorouracil are comparatively effective as monotherapy, but botulinum toxin-A was not effective on established hypertrophic scars.

Effects of hyperbaric oxygen therapy on biochemical and histological parameters of muscle groups in proximity to the distracted rat tibia.

We investigated the effect of hyperbaric oxygen therapy (HBOT) on rat muscles during tibial distraction osteogenesis (DO) at normal and hyperdistraction rates. Animals in groups 1 and 2 were distracted by 0.5 mm/day and those in groups 3 and 4 by 1 mm/day. Groups 2 and 4 received HBOT during distraction. Group 5 served as control. Superoxide dismutase (SOD; U/g protein), malondialdehyde (nmol/g protein), glutathione (mmol/g protein), and protein levels (g/dl) were determined. SOD was significantly higher in group 2 (4.59 ± 0.97) than in controls (2.19 ± 0.7) (P = 0.0001), and lower in group 4 (3.74 ± 1.70) than in group 2 (P=0.011). Malondialdehyde was significantly higher in group 2 (0.72 ± 0.23) than in controls (0.38 ± 0.10) (P=0.005). Total protein levels were better preserved with HBOT in distracted muscles: group 2 (3.24 ± 0.37) vs. group 1 (1.88 ± 0.60), and group 4 (3.45 ± 0.70) vs. group 3 (2.03 ± 0.75) (both P=0.0001). Numbers of fibres were lower in group 1 (4.88 ± 0.59) than in group 2 (6.07 ± 0.86), and in group 3 (5.13 ± 0.36) than in group 4 (6.14 ± 0.74) (both P=0.001). Numbers of nuclei were higher in group 1 (11.29 ± 2.47) than in group 2 (9.03 ± 1.53) (P=0.04), and in group 3 (12.43 ± 3.32) than in group 4 (9.08 ± 1.58) (P=0.001). Fibres and nuclei with HBOT were similar to those of controls. HBOT decreased the inflammatory cell infiltrate for group 1 (19.8 ± 8.54) vs. group 2 (4.2 ± 2.53) and group 3 (36.54 ± 11.29) vs. group 4 (21.5 ± 9.23) (both P=0.001). HBOT improves the adaptation of distracted muscle by increasing fibres and antioxidants while decreasing inflammation.