title: Extraluminal helicoidal stretch (Helixtretch): a novel method of intestinal lengthening.
abstract: OBJECTIVE
  We sought to test a novel, extraluminal method of intestinal lengthening that precludes violation of the intestinal wall.
  
  
  METHODS
  Sprague-Dawley rats (n=45) with size-matched bowel segments isolated by Roux-en-Y reconstruction were divided into three groups. Group 1 (n=14) had no further manipulations. In Groups 2 (n=12) and 3 (n=19), the isolated segment was wrapped around a length-matched device in a helicoidal fashion. In Group 2, the device consisted of plain polyurethane tubing. In Group 3, it consisted of a gradually expanding hygroscopic hydrogel (12.5mm final diameter). Euthanasia was performed at 8-21 days. Statistical analysis was by two-way ANOVA (P<0.05).
  
  
  RESULTS
  Overall survival was 87% (39/45). There was a statistically significant increase in bowel length in Group 3 compared to the other two groups (P<0.001). This increase correlated with the number of helicoidal coils (P=0.018), but not with post-operative time (P>0.50). There were no significant differences in total DNA/protein ratio across the groups (P=0.65). Histologically, there was an apparent increase in the goblet cell density in Group 3.
  
  
  CONCLUSIONS
  Measured extraluminal helicoidal stretch (Helixtretch) is tolerated by the intestine. Helixtretch induces bowel lengthening in a rodent model. Further analysis of this novel, minimally invasive alternative for intestinal augmentation is warranted.
authors.affiliation: Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Beatrice
authors.initials: B
authors.lastname: Dionigi
authors.affiliation: Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Joseph
authors.initials: J
authors.lastname: Brazzo
authors.affiliation: Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: John Patrick
authors.initials: JP
authors.lastname: Connors
authors.affiliation: Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Azra
authors.initials: A
authors.lastname: Ahmed
authors.affiliation: Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: Jeremy G
authors.initials: JG
authors.lastname: Fisher
authors.affiliation: Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts.
authors.forename: David
authors.initials: D
authors.lastname: Zurakowski
authors.affiliation: Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts. Electronic address: dario.fauza@childrens.harvard.edu.
authors.forename: Dario O
authors.initials: DO
authors.lastname: Fauza
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000008:administration & dosage*; D007267:Injections; D007422:Intestines / Q000601:surgery*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012778:Short Bowel Syndrome / Q000601:surgery*; D015626:Tissue Expansion / Q000379:methods*
chemical_list: D020136:Hydrogel, Polyethylene Glycol Dimethacrylate
keywords: Helicoidal stretch; Helix; Intestinal lengthening; Intestinal stretch; Short bowel syndrome