title: Tissue-engineered calcium alginate patches in the repair of chronic chinchilla tympanic membrane perforations.
abstract: OBJECTIVE
  Chronic tympanic membrane perforations are a common problem in the United States. A high number of these cases results from placement of pressure equalization tubes. These perforations may initially be treated with paper patch techniques and although safe and well tolerated, the procedure demonstrates poor efficacy. The ideal treatment for small perforations should be rapid, minimally invasive, and efficacious. Calcium alginate-based tissue engineered tympanic membrane patches represent an attractive option, but in vivo data are required.
  
  
  METHODS
  A controlled prospective study of tympanic membrane perforation repair using a well-known chinchilla model of chronic tympanic membrane perforation was performed. Calcium alginate-based tympanic membrane patches were created using computer-aided design techniques. A previously described chinchilla model of chronic tympanic membrane perforations was used to create stable perforations ranging from 2 to 5 mm. Ears with chronic perforations were divided into three groups: control (no patch), paper patch, and calcium alginate plugs. At 10 weeks postimplantation, all animals were killed and inspected both grossly and histologically for healing.
  
  
  RESULTS
  In the chinchilla model, the alginate grafts demonstrated significantly improved healing rates over both the untreated control group (spontaneous repair) and the paper patch group; nine of 13 healed in the alginate group versus two of nine healed in the paper patch group (P < .05) versus one of 11 healed in the control group (P < .05).
  
  
  CONCLUSIONS
  Calcium alginate tympanic membrane perforation patches offer a significant advantage in the repair of chronic perforations over traditional techniques in the chinchilla perforation model and may offer attractive opportunities in the clinical setting.
authors.affiliation: Department of Otolaryngology and Head and Neck Surgery, University Hospitals of Cleveland, Case Western Reserve University, Cleveland, Ohio 44106, USA.
authors.forename: David E
authors.initials: DE
authors.lastname: Weber
authors.forename: Maroun T
authors.initials: MT
authors.lastname: Semaan
authors.forename: Jay K
authors.initials: JK
authors.lastname: Wasman
authors.forename: Richard
authors.initials: R
authors.lastname: Beane
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Bonassar
authors.forename: Cliff A
authors.initials: CA
authors.lastname: Megerian
mesh_terms: D000464:Alginates / Q000494:pharmacology*; D000818:Animals; D001707:Biopsy, Needle; D002682:Chinchilla; D002908:Chronic Disease; D004195:Disease Models, Animal; D005260:Female; D020723:Glucuronic Acid / Q000494:pharmacology; D006084:Graft Rejection; D006085:Graft Survival; D006320:Hearing Tests; D006603:Hexuronic Acids / Q000494:pharmacology; D007150:Immunohistochemistry; D011897:Random Allocation; D012307:Risk Factors; D023822:Tissue Engineering; D016378:Tissue Transplantation / Q000379:methods*; D016896:Treatment Outcome; D018058:Tympanic Membrane Perforation / Q000473:pathology / Q000601:surgery*
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D020723:Glucuronic Acid