title: Choledochojejunostomy with an innovative magnetic compressive anastomosis: How to determine optimal pressure?
abstract: OBJECTIVE
  To investigate the optimal magnetic pressure and provide a theoretical basis for choledochojejunostomy magnetic compressive anastomosis (magnamosis).
  
  
  METHODS
  Four groups of neodymium-iron-boron magnets with different magnetic pressures of 0.1, 0.2, 0.3 and 0.4 MPa were used to complete the choledochojejunostomy magnamosis. Twenty-six young mongrel dogs were randomly divided into five groups: four groups with different magnetic pressures and 1 group with a hand-suture anastomosis. Serum bilirubin levels were measured in all groups before and 1 wk, 2 wk, 3 wk, 1 mo and 3 mo after surgery. Daily abdominal X-ray fluoroscopy was carried out postoperatively to detect the path and the excretion of the magnet. The animals were euthanized at 1 or 3 mo after the operation, the burst pressure was detected in each anastomosis, and the gross appearance and histology were compared according to the observation.
  
  
  RESULTS
  The surgical procedures were all successfully performed in animals. However, animals of group D (magnetic pressure of 0.4 MPa) all experienced complications with bile leakage (4/4), whereas half of animals in group A (magnetic pressure of 0.1 MPa) experienced complications (3/6), 1 animal in the manual group E developed anastomotic stenosis, and animals in group B and group C (magnetic pressure of 0.2 MPa and 0.3 MPa, respectively) all healed well without complications. These results also suggested that the time required to form the stoma was inversely proportional to the magnetic pressure; however, the burst pressure of group A was smaller than those of the other groups at 1 mo (187.5 ± 17.7 vs 290 ± 10/296.7 ± 5.7/287.5 ± 3.5, P < 0.05); the remaining groups did not differ significantly. A histologic examination demonstrated obvious differences between the magnamosis groups and the hand-sewn group.
  
  
  CONCLUSIONS
  We proved that the optimal range for choledochojejunostomy magnamosis is 0.2 MPa to 0.3 MPa, which will help to improve the clinical application of this technique in the future.
authors.affiliation: Fei Xue, Jian-Peng Li, Jian-Wen Lu, Yi Lv, Department of Hepatobiliary Surgery, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Xue
authors.affiliation: Fei Xue, Jian-Peng Li, Jian-Wen Lu, Yi Lv, Department of Hepatobiliary Surgery, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China.
authors.forename: Hong-Chang
authors.initials: HC
authors.lastname: Guo
authors.affiliation: Fei Xue, Jian-Peng Li, Jian-Wen Lu, Yi Lv, Department of Hepatobiliary Surgery, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China.
authors.forename: Jian-Peng
authors.initials: JP
authors.lastname: Li
authors.affiliation: Fei Xue, Jian-Peng Li, Jian-Wen Lu, Yi Lv, Department of Hepatobiliary Surgery, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China.
authors.forename: Jian-Wen
authors.initials: JW
authors.lastname: Lu
authors.affiliation: Fei Xue, Jian-Peng Li, Jian-Wen Lu, Yi Lv, Department of Hepatobiliary Surgery, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China.
authors.forename: Hao-Hua
authors.initials: HH
authors.lastname: Wang
authors.affiliation: Fei Xue, Jian-Peng Li, Jian-Wen Lu, Yi Lv, Department of Hepatobiliary Surgery, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Ma
authors.affiliation: Fei Xue, Jian-Peng Li, Jian-Wen Lu, Yi Lv, Department of Hepatobiliary Surgery, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China.
authors.forename: Ya-Xiong
authors.initials: YX
authors.lastname: Liu
authors.affiliation: Fei Xue, Jian-Peng Li, Jian-Wen Lu, Yi Lv, Department of Hepatobiliary Surgery, First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Lv
mesh_terms: D057868:Anastomotic Leak / Q000097:blood / Q000209:etiology; D000818:Animals; D001663:Bilirubin / Q000097:blood; D015415:Biomarkers / Q000097:blood; D002768:Choledochostomy / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D002779:Cholestasis / Q000097:blood / Q000601:surgery*; D004195:Disease Models, Animal; D004285:Dogs; D004867:Equipment Design; D005240:Feasibility Studies; D008280:Magnetics / Q000295:instrumentation*; D059346:Magnets / Q000009:adverse effects; D008297:Male; D011312:Pressure; D013536:Suture Techniques; D013997:Time Factors
chemical_list: D015415:Biomarkers; D001663:Bilirubin
keywords: Choledochojejunostomy; Magnetic compressive anastomosis; Magnetic pressure; Optimal range; Pressure intensity