The Healing Pattern of Experimental Pars Flaccida Perforations

Abstract

The aim of this investigation was to ascertain how a traumatic perforation of the pars flaccida heals and whether this could explain the way in which the retraction pocket develops. In rats, traumatic pars flaccida perforations were performed on both ears and the healing pattern was registered after various intervals. The perforations healed in 7–10 days, forming in the first instance an in-drawing of the pars flaccida and after 12–14 days an adhesive retraction, i.e., the pars flaccida adhered to the neck of malleus. The retraction pocket was filled with wax, keratin and detritus. At the base of the retraction, epithelial inclusions could be found, which could explain why these retractions were not self-cleaning.