Homograft replacement of the tympanic membrane

Abstract

This paper presents the authors' experiences with one method of reconstruction of the tympanic membrane when it is totally absent or when there is a fixed, retracted, defective, or absent malleus. Ten patients undergoing surgery for chronic suppurative otitis media between April, 1971, and January, 1973, had homograft tympanic membranes and/or ossicles used to reconstruct the defect in the tympanic membrane or ossicular mechanism. The patients had certain clinical and surgical characteristics in common: 1. all had either an absent tympanic membrane or almost total perforation of it; 2. all were operated upon in the absence of acute infection or active drainage; cholesteatoma, if present, was totally removed; 3. all had patent eustachian tubes; 4. all had intact middle ear mucosa at the time of utilization of the homograft; 5. all patients were operated upon by the same surgeon; 6. all of the homografts were obtained within 24 hours and were used within one month after the death of the donor; 7. all of the homografts used had been preserved in 70 percent ethyl alcohol; 8. all of the homograft materials came from donors who were under 40 years of age at the time of death and who died of accidental causes. (None of the donors was known to have any pre-existing disease); 9. all homografts, after being placed in proper position in the recipient, were covered with ear canal skin; 10. all patients received homografts that were from the corresponding ear of the donor. (In other words, right ear homografts were used in the patient's right ear, etc.); 11. whenever the tympanic ring was greater than the size of the homograft, the patient's temporalis fascia was used in conjunction with the homograft tympanic membrane to bridge the defect; 12. all patients had the middle ear packed with gelfoam prior to inserting the homograft (compressed gelfoam was used also for the outer packing); 13. none of the patients had tissue-typing procedures carried out in an effort to match the donor and the recipient, nor was any attempt made to match the sex of the donor and the recipient; and 14. all patients received antibiotics postoperatively; however, none received immunosuppressive therapy postoperatively. In 3 of 10 patients receiving homografts, the malleus was normal, and only the tympanic membrane was reconstructed. In seven others there was a fixed, retracted, defective or absent malleus in addition to the tympanic membrane defect.(ABSTRACT TRUNCATED AT 400 WORDS)

Panel 3: Genetics and Precision Medicine of Otitis Media

“…Clinically, the middle ear is considered an immune‐privileged area 76 . Homografts of the tympanic member usually survive for a long time without administration of any immunosuppressive drugs after surgery 77 . For this reason, the middle ear is tolerant to the invading upper respiratory commensals that reside and thrive, frequently causing OM.…”

“…76 Homografts of the tympanic member usually survive for a long time without administration of any immunosuppressive drugs after surgery. 77 For this reason, the middle ear is tolerant to the invading upper respiratory commensals that reside and thrive, frequently causing OM. Consistent with this, immune- and inflammatory-related cytokines, such as TNFa and interferon gamma, 78,79 are induced, which regulate the immunity of the middle ear mucosa against infectious agents.…”

Role of Growth factors (HB-EGF, VEGF-A) and Immunotolerance Mediators (TNF-αIFN-γ,PD-L1 and IL-10) in Acute and Chronic Otitis Media

“…One of the proposed hypothesis for the chronic or recurrent OM is immunotolerance or compromised innate or adaptive immunity (Alford et al, 1976). Duringthe acute condition, the middle ear epithelial cells starts producing first level cytokines in response to pathogenic infection via the NF-κBsignalingpathway (Li, et al, 2002; Rhodus et al, 2005).…”

Adaptive Immunity in the Middle Ear Mucosa with Chronic Otitis Media

“…It has long been recognized that there is immunotolerance towards ossicular grafts and tympanic membrane implants. Homografts of the tympanic member are able to exist for a long time without administration of any immunosuppressive drugs after surgery [10]. This suggests that immunotolerance does occur in the middle ear to a certain degree, not fully but sufficient enough to allow homografts to survive.…”