Tierexperimentelle untersuchung von einheilungsvorgängen heterologer trommelfellimplantate

Summary

Tympanic membranes of guinea pigs were replaced by human tympanic membranes preserved in Cialit solutions. The implanted tissues were removed after various time intervals (5 days to 5 months) and prepared for histological and/or histochemical examinations. Normal tympanic membranes, both from guinea pig and man, were subjected to the same examinations.

These studies showed that the re-vitalization of the heterological implants occurred in several distinct phases. After the fiftht day already, granulation tissues were found in the border areas. Eosinophils and lymphocytes were present indicative of immunological reactions. However, their presence did not affect the repair process. After the second week, there was an intact epithelial layer and also a mucous-membrane lining on the tympanic side. Enzymatic reactions in these epithelia was much stronger than those found in normal tympanic membranes. The fibrous layers of the implants were gradually incorporated beginning at their own borders. After 5 months, this process was not completed, the most likely reason being that the dimensions of the guinea pig's middle ear are too small compared to the thickness of the implant. Thus, even after 5 months, the enzyme complement of the implant was still deficient when compared to that of a normal tympanic membrane. Enzyme-histochemical methods permitted to delineate clearly the dead foreign tissues from the life and actively-regenerating host tissues. Tympanic membranes preserved in Cialit are tolerated by the host tissues and act as their plates.

Zusammenfassung

Meerschweinchen-Trommelfelle wurden durch menschliche, in Cialit konservierte Trommelfellanteile ersetzt. Die Implantate wurden nach verschiedenen Zeitintervallen — nach 5 Tagen his maximal 5 Monaten — wieder entnommen und histologisch Bowie enzymhistochemisch aufgearbeitet. Dieselben Untersuchungen erfolgten gleichzeitig zu Vergleichszwecken an normalen menschlichen und Meerschweinchen-Trommelfellen.

Mit Hilfe der versehiedenen Untersuchungsmethoden konnte gezeigt wurden, daß die Revitalisierung der heterologen Implantate zeitlich in versehiedenen Phasen abläuft.