Cryosurgery to remove perichondrium for the rabbit ear hypertrophic scar model: a simplified method

Abstract

The rabbit ear hypertrophic scar model is a preferred animal model of excessive scarring for investigating the scarring process and novel treatment modalities. In this model, surgical removal of perichondrium can be challenging, and it is often insufficient or damages the underlying cartilage. It is hypothesized that cryosurgery would offer a more efficient alternative to conventional surgery. The objective of this study was to compare structural changes in scar tissues in two groups of the hypertrophic scar model: cryosurgery compared to standard conventional surgery. We introduced a novel technique to remove perichondrium using cryosurgery. Hypertrophic scars obtained with conventional surgery and cryosurgery were studied in a left-right comparison method. Comparative parameters included the histological structure of the scars and structural changes in the cartilage just beneath the scarring. Cryosurgery produced similar scars in comparison to conventional surgery. Although statistically not significant (p = 0.16), the histological findings of cartilage damage were lower in the cryosurgery group (six out of 21) compared to the established model (10 out of 20). This study suggests that cryotherapy can be used for removal of perichondrium.