Magnetic recanalization technique for the treatment of alimentray tract stricture: A clinical study

Y. Li
M. Su
X. Sun
L. Yu
C. Liu
S. He
R. Wu, Zucker School of Medicine at Hofstra/Northwell
H. Sun


© 2020, Science Press. All right reserved. Magnetic compression anastomosis or magnetic recanalization technique is a revolutionary minimally invasive method to perform re-anastomosis in patients with alimentary strictures. We conduct magnetic recanalization for the treatment of severe alimentary strictures that cannot be treated by conventional methods. Data are analysed retrospectively in order to investigate the safety and efficiency of this method. From 2012 January to 2019 October, 17 patients with alimentary stricture after operation were enrolled in the first affiliated hospital of Xi'an Jiaotong University and the Chinese PLA General Hospital. The ages were 47±16.8 years, and 11 cases were men. 17 cases include 14 benign biliary strictures, two esophageal strictures and one colorectal anastomosis strictures. 14 cases are complete strictures, and the others are refractory one. Strictures are found 0-120 months after the last operation. All the patients have undergone 2-8 times unsuccessful standard treatments, including endoscopic retrograde cholangiopancreatography (ERCP), percutaneous transhepatic cholangial drainage (PTCD) or endoscopic balloon dilation. Magnetic recanalization technique (MRT) is proposed. The MRT device consists of two identical, nickel-plated NdFeB magnets (rating, N45) termed the parent magnet and the daughter magnet. Each magnet shapes like a cylinder or annular. The daughter and parent magnet are delivered to the proximal and distal end of stricture respectively via different routes. The attraction force between the two magnets leads to necrosis of the fibrotic stricture tissue and the creation of a new transmural anastomosis. Thereafter, stent deployment or balloon dilation is performed to the new anastomosis. Data about stricture length, recanalization time, side effects in 30 days, time to remove the biliary stent and stricture recurrence are collected. All the patients are followed-up to 2019 December by telephone or outpatients service. After the MRT, 1 case fails. Magnets can couple stably in 16 patients (successful rate 94.1%), including 10 cases of choledocho-choledochostomy, 3 cases of bilio-enteric anastomosis, 1 case of esophago-esophagostomy, 1 case of esophago-gastrostomy and 1 case of colo-proctostomy. The delivery routes are per-PTCD/per-ERCP, per-PTCD or drainage tube sinus/per-gastroscope, per-gastroscope/per-gastroscope, per-gastroscope/per-operation and per-enterostomy/per-anus respectively. The daughter and parent magnets detach from each other in 3 patients after days post-MRT. The magnets couple automatically in 2 patients without any interventions. In the other patient, another daughter magnet is added through PTCD, and the magnets are again tightly approximated. Three adverse events are found (cholangitis, 1 patient; biliary bleeding, 1 patient; colon leakage, 1 patient), but are resolved with conservative treatment. The stricture length is 2-7.1(4±1.9) mm in successful cases, and recanalization occurs after 7-50 (15.5±10.6) days. Biliary multiple plastic stents (4 patients), biliary fully covered self-expandable metallic stent (5 patients), percutaneous trans-hepatic cholangiodrainage catheter (4 patients), balloon dilation plus metallic stent (2 patients), or balloon dilation alone (1 patient) is used after recanalization. Stents are retrieved after 6.9±4.0 months in 14 patients, and 1 patient is still in stent period. During 3-70 months of stent-free follow-up, no stenosis is found in 13 biliary stricture patients, but 2 cases are found biliary stones and cured by endoscopic treatment. Two of three patients with esophageal or colorectal anastomosis stricture experience recurrence in follow up, and are still managed by endoscopic ways. In conclusion, magnetic recanalization technique is a minimally invasive, effective and safe method to complicated alimentary stricture, and can serve as a remedial method when conventional ways fail.