Hypothesis: Autologous epidermal sheets obtained by cultivating keratinocytes of the external auditory meatus can be used to repair cutaneous defects of the ear canal. The Rheinwald and Green method has been used to know whether the produced epidermal layer preserves its specificities after the culture.
Background: Using a split-thickness skin graft during a functional ear atresia surgery does not allow for the restitution of external auditory canal self-cleaning. Some authors cultivated external auditory meatus keratinocytes and showed migration capacities of these colonies.
Methods: Samples of preauricular skin and of the bony part of the external auditory canal were harvested from 10 patients. Keratinocytes were extracted and cultured until an epidermal sheet was obtained. The output, the keratinocyte plating efficiency, and the production delay were measured during the culture. Culture product sections and biopsy sections were examined using optical microscopy after standard coloration and indirect immunohistochemistry.
Results: Nine epidermal layers from 10 biopsies were obtained in each group. A significant difference between external auditory meatus and preauricular keratinocyte plating efficiency was highlighted. The average production delay of 23 cm2 external auditory canal and preauricular epidermal layers was 21 days. There was no difference in the cytokeratine expression between external auditory canal and preauricular skin, nor between external auditory canal and preauricular culture products. All cultures expressed the cytokeratine 5 characteristic of stratifying epithelium.
Conclusion: The Rheinwald and Green keratinocyte culture method allows the production of ear canal-stratified epidermal sheets, which can be used for external ear reconstruction.