Autologous nanofat harvested from donor site of full-thickness skin or skin flap grafting for the treatment of early postburn scarring: a case series

Introduction

Postburn scarring often presents a specific reconstructive challenge from both functional and cosmetic perspectives. The purpose of this study was to investigate whether autologous nanofat harvested from the donor site of full skin or a skin flap can be reused for the treatment of early postburn scaring.

Methods

From July 2018 to April 2022, patients with early postburn scarring underwent scar reconstruction surgery with full-thickness skin or a skin flap for a contour deformity and/or scar contracture, and autologous nanofat grafting was performed during the same operation. The Vancouver Scar Score (VSS) and the itch and pain scores were evaluated at the preoperation time point as well as at 2-3 weeks and 3-months postoperation. A comparison was made among the same patients at different time points.

Results

A total of 17 patients, aged from 18 months to 62 years old were included in this analysis. The VSS was reduced from 10.00 ± 2.12 to 7.41 ± 1.277 at the 2-3-week postoperation time point, and to 5.53 ± 1.37 at the 3-month postoperation time point. The pain and itch score were reduced from 4.65 ± 1.37 and 6.35 ± 1.27, to 3.70 ± 1.10 and 4.94 ± 1.30 at the 2-3-week postoperation time point, and to 3.00 ± 1.28 and 3.94 ± 0.97 at the 3-month postoperation time point respectively. The VSS and pain and itch scores showed a statistically significant reduction (P < 0.05) at the 2-3-week and 3-month postoperative follow-ups compared with the preoperation time point.

Conclusion

Autologous nanofat grafting from donor sites of full thickness skin or skin flap may be a promising treatment for an early postburn scaring as it promotes scar softening, improves itching and pain within the scar. However, this is a small case series with only 17 patients. Further conclusions need to be drawn through expanded samples for randomized controlled clinical trials.

Lay Summary

Hypertrophic scarring is the most common complication after partial thickness burn injury, and the complex pathogenesis and prolonged dynamic process render treatments only marginally effective. In the past few decades, with the technological advances of liposuction and fat grafting, nanofat grafting has been used in a variety of surgical fields, including wound healing, scleroderma, facial rejuvenation, and neuralgia. However, the role of nanofat grafting is not well documented in the prevention and treatment of early postburn scarring. Full-thickness skin grafting or skin flap transplantation is the most common method for the reconstruction of a hypertrophic scaring until now. In the current study, we harvested subcutaneous fat during the preparation of the full-thickness skin or skin flap, prepared nanofat and injected it in the scar located at a nonsurgical site. Comparison of the pre- and postoperation scores for scar color, scar thickness, scar stiffness, and scar regularity showed that the postoperation scores were decreased significantly and that there was a significant improvement in scar pigmentation and thickness as well astheaesthetic outcome after treatment. Most importantly, reductions in the scores for pain and itching could be assessed objectively. It seems that the nanofat grafting is a potential method for prevention and treatment for early postburn scaring.

The Tensile Strength of Full-Thickness Skin: A Laboratory Study Prior to Its Use as Reinforcement in Parastomal Hernia Repair

Purpose: Parastomal hernia is a common complication of an enterostoma. Current methods of repair have high recurrence rates and are associated with severe complications. Autologous full-thickness skin as reinforcement may reduce the recurrence and complication rates. This study aims to investigates the tensile strength of full-thickness skin; information that is essential if we are to proceed with clinical trials on humans.

Methods: Full-thickness skin samples from 12 donors were tested for tensile strength, as well as the load tolerated by a suture through the skin. Strips of skin were cut out and stretched until breaking point. Sutures were made through skin samples and traction applied until either the tissue or the suture gave way. All done while recording the forces applied using a dynamometer. Identical tests were carried out on commercially available synthetic and biologic graft material for comparison.

Results: The full-thickness skin strips had a median tensile strength of 604 N/cm. This tensile strength was significantly higher than that of the compared materials evaluated in this study. In full-thickness skin, the suture, or tissue endured a median force of 67 N before giving way, which was as high as, or higher than similar sutures through the compared materials.

Conclusions: The tensile strength of full-thickness skin vastly exceeds the physiological forces affecting the abdominal wall, and sutures through skin endure high loads before giving way. The tensile strength of a full-thickness skin graft and the strength of sutures through this material will not limit its use for reinforcement in parastomal hernia repair.

Characterization of a New Reconstructed Full Thickness Skin Model, T-Skin™, and its Application for Investigations of Anti-Aging Compounds

BACKGROUND

We have characterized a new reconstructed full-thickness skin model, T-Skin™, compared to normal human skin (NHS) and evaluated its use in testing anti-aging compounds.

METHODS

The structure and layer-specific markers were compared with NHS using histological and immunohistological staining. In anti-aging experiments, T-SkinTM was exposed to retinol (10 µM) or vitamin C (200 µM) for 5 days, followed by immunohistological staining evaluation.

RESULTS

T-Skin™ exhibits a well stratified, differentiated and self-renewing epidermis with a dermal compartment of functional fibroblasts. Epidermal (cytokeratin 10, transglutaminase 1), dermo-epidermal junction (DEJ) (laminin 5, collagen-IV, collagen VII) and dermally-located (fibrillin 1, procollagen I) biomarkers were similar to those in NHS. Treatment of T-Skin™ with retinol decreased the expression of differentiation markers, cytokeratin 10 and transglutaminase 1 and increased the proliferation marker, Ki67, in epidermis basal-layer cells. Vitamin C increased the expression of DEJ components, collagen IV and VII and dermal procollagen 1.

CONCLUSIONS

T-Skin™ exhibits structural and biomarker location characteristics similar to NHS. Responses of T-Skin™ to retinol and vitamin C treatment were consistent with those of their known anti-aging effects. T-Skin™ is a promising model to investigate responses of epidermal, DEJ and dermal regions to new skin anti-ageing compounds.