Mohammad farhadi - ENT and Head & Neck Research Center and Department, Hazrat Rasoul Akram Hospital, Iran University of Medical Sciences, Tehran, Iran

Chronic tympanic membrane (TM) perforation as the most common complication of ontological diseases may cause hearing loss and worsen middle ear infection.several studies used various graft materials, paper patches, cell-seeded and tissue engineered grafts to have been used for TM grafting. In this study Polydimethyl siloxane (PDMS) that is biomaterial patch modified surface to improve biocompatibility, hydrophilicity and cell adhesion.ObjectivesThis aim achieved by creating acrylic acid (AAc) grafting that was used to chemically immobilize collagen type I. The potential of this biologically modified collagen-immobilized PDMS (CI-PDMS) as a tympanic patch was evaluated both in vitro and in vivo.ResultsResult indicated present of collagen increase significantly biocompatibility and cell attachment on the PDMS patches and its suitability as a substrate for cell growth. An in vivo assay of the patch forinitiating repair of TM perforations also was investigated. In in vivo study, the overall complete closure of small TM perforations in seven out of 10 cases (70%) and an average gain of 15.75 6 4.29 dB in air-bone gap were observed. It shows that CI-PDMS can serve allowing the patient’s fibroblasts to grow and proliferate on the graft and confirmed the in vitro study. This in vivo evaluation of a modified patch in humans had promising results and is comparable to existing biomaterial patches in TM perforations.ConclusionOther than adhesion, growth and proliferation of cells toward our patch, its good manipulationproperties, easy adhesion to TM surfaces, full transparency, which could let surgeons observe the edges of the margins during surgery and allowing the possibility of following up the healing processes of the perforations were other advantages of CI-PDMS patches.

Chronic tympanic membrane, Perforation, PDMS, Biocompatibility