Pathology Epithelial migration: the edge of a peripheral perforation Inward growth of the surface epithelium follows papillary proliferation of the germinative layer of the pars flaccida o Metaplasia from pseudostratified ciliated columnar epitheliumPathology ◼ Epithelial migration: the edge of a peripheral perforation ◼ Inward growth of the surface epithelium follows papillary proliferation of the germinative layer of the pars flaccida. ◼ Metaplasia from pseudostratified ciliated columnar epithelium