title: Use of small intestinal submucosal and acellular dermal matrix grafts in giant omphaloceles in neonates and a rabbit abdominal wall defect model.
abstract: BACKGROUND
  The described surgical strategies for the management of omphalocele include primary closure, staged closure, and delayed closure. A primary repair is not suitable for all giant omphaloceles. We implanted two grafts, small intestinal submucosal (SIS) and acellular dermal matrix (ADM) onto abdominal wall defects in neonates to study the safety and efficacy of SIS and ADM graft techniques for initial closure of giant omphaloceles in infants, and we also implanted these grafts onto abdominal wall defects in an animal model.
  
  
  METHODS
  Twenty-four patients with giant omphaloceles were divided into two groups (ADM group, 12 patients; SIS group, 12 patients). The operative time, skin healing time postoperatively, and the incidence of skin infections, and abdominal wall hernias were observed. In the rabbit animal model, bilateral full-thickness incisions were made through the rabbit rectus abdominus muscles and a 2×4cm longitudinal whole layer defect was created on either the left or right lateral anterior abdominal wall. A four-layered variant of the SIS graft was used to repair the right abdominal defect; ADM was used to repair the left. Tensile strength was measured using an Instron tensiometer. Electron scanning and light microscopy were used to evaluate neovascularization, collagen deposition, and muscle fibers at 2, 4, 8, and 16weeks postimplantation.
  
  
  RESULTS
  In the neonatal patients, there was no statistically significant difference between the two groups with respect to operative time, skin healing time postoperatively, the incidence of skin infections, or abdominal wall hernias. In the SIS group, only one patient developed a skin infection, which led to skin necrosis and sloughing. In the ADM group, four patients developed skin infection postoperatively, and the patch was gradually removed. In the animal study, there was no significant difference between the mean breaking strength of ADM versus SIS repairs. Scanning electron and light microscopy showed collagen deposition, increased vascularization, fibroblasts, and muscular regeneration in both SIS and ADM repairs. SEM showed that the SIS graft was absorbed, while ADM was not. Light microscopy showed foreign body macrophages in ADM, but not in the SIS repairs.
  
  
  CONCLUSIONS
  SIS and ADM grafts adequately enhance healing with a low complication rate. Compared with ADM grafts, SIS is absorbable, induces less inflammation, and is more biocompatible, and therefore might be more useful and suitable for closure of abdominal wall defects.
authors.affiliation: Department of Neonatal Surgery, Nanjing Children's Hospital Affiliated to Nanjing Medical University, Nanjing, 210008, China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Jiang
authors.affiliation: Department of Neonatal Surgery, Nanjing Children's Hospital Affiliated to Nanjing Medical University, Nanjing, 210008, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Neonatal Surgery, Nanjing Children's Hospital Affiliated to Nanjing Medical University, Nanjing, 210008, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Lv
authors.affiliation: Department of Neonatal Surgery, Nanjing Children's Hospital Affiliated to Nanjing Medical University, Nanjing, 210008, China.
authors.forename: Changgui
authors.initials: C
authors.lastname: Lu
authors.affiliation: Department of Neonatal Surgery, Nanjing Children's Hospital Affiliated to Nanjing Medical University, Nanjing, 210008, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Chen
authors.affiliation: Department of Neonatal Surgery, Nanjing Children's Hospital Affiliated to Nanjing Medical University, Nanjing, 210008, China.
authors.forename: Xiaoqun
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Neonatal Surgery, Nanjing Children's Hospital Affiliated to Nanjing Medical University, Nanjing, 210008, China. Electronic address: tangweibingcn@163.com.
authors.forename: Weibing
authors.initials: W
authors.lastname: Tang
mesh_terms: D034861:Abdominal Wall / Q000601:surgery; D062088:Acellular Dermis; D000818:Animals; D005260:Female; D006554:Hernia, Umbilical / Q000601:surgery*; D059685:Herniorrhaphy / Q000379:methods*; D006801:Humans; D007231:Infant, Newborn; D007413:Intestinal Mucosa / Q000637:transplantation*; D007421:Intestine, Small / Q000637:transplantation*; D008297:Male; D011817:Rabbits; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: Small intestinal submucosa; acellular dermal matrix; omphaloceles