• Journal of Digestive Cancer Research
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• v.10 no.2
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• pp.92-98
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• 2022

Self-expandable metal stent (SEMS) is effective for biliary drainage, especially in pancreaticobiliary cancer. The mechanical properties, material, and design of SEMS are important in preventing recurrent biliary obstruction and complication. Radial and chronic expansion forces play roles in preventing stent migration and collapse. Complications, such as stent impaction, cholecystitis, and pancreatitis, were related to the axial force. The nickel-titanium alloy shows more flexibility, conformability, and optimal axial force compared to previously used stainless steel. Additionally, the stent structure affected the mechanical properties of SEMS. Therefore, understanding the mechanical properties, material, and design of SEMS will provide the best outcome for biliary drainage, as well as better SEMS development.

• Clinical Endoscopy
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• v.56 no.2
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• pp.135-142
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• 2023

Endoscopic biliary drainage strategies for managing unresectable malignant hilar biliary obstruction differ in terms of stent type, drainage area, and deployment method. However, the optimal endoscopic drainage strategy remains unclear. Uncovered self-expandable metal stents (SEMS) are the preferred type because of their higher functional success rate, longer time to recurrent biliary obstruction (RBO), and fewer cases of reintervention than plastic stents (PS). Other PS subtypes and covered SEMS, which feature a longer time to RBO than PS, can be removed during reintervention for RBO. Bilateral SEMS placement is associated with a longer time to RBO and a longer survival time than unilateral SEMS placement. Unilateral drainage is acceptable if a drainage volume of greater than 50% of the total liver volume can be achieved. In terms of deployment method, no differences were observed in clinical outcomes between side-by-side (SBS) and stent-in-stent deployment. Simultaneous SBS boasts a shorter procedure time and higher technical success rate than sequential SBS. This review of previous studies aimed to clarify the optimal endoscopic biliary drainage strategy for unresectable malignant hilar biliary obstruction.

• Journal of Gastric Cancer
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• v.18 no.1
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• pp.37-47
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• 2018

Purpose: The endoscopic management of a fully covered self-expandable metal stent (SEMS) has been suggested for the primary treatment of patients with anastomotic leaks after total gastrectomy. Embedded stents due to tissue ingrowth and migration are the main obstacles in endoscopic stent management. Materials and Methods: The effectiveness and safety of endoscopic management were evaluated for anastomotic leaks when using a benign fully covered SEMS with an anchoring thread and thick silicone covering the membrane to prevent stent embedding and migration. We retrospectively reviewed the data of 14 consecutive patients with gastric cancer and anastomotic leaks after total gastrectomy treated from January 2009 to December 2016. Results: The technical success rate of endoscopic stent replacement was 100%, and the rate of complete leaks closure was 85.7% (n=12). The mean size of leaks was 13.1 mm (range, 3-30 mm). The time interval from operation to stent replacement was 10.7 days (range, 3-35 days) and the interval from stent replacement to extraction was 32.3 days (range, 18-49 days). The complication rate was 14.1%, and included a single jejunal ulcer and delayed stricture at the site of leakage. No embedded stent or migration occurred. Two patients died due to progression of pneumonia and septic shock 2 weeks after stent replacement. Conclusions: A benign fully covered SEMS with an anchoring thread and thick membrane is an effective and safe stent in patients with anastomotic leaks after total gastrectomy. The novelty of this stent is that it provides complete prevention of stent migration and embedding, compared with conventional fully covered SEMS.

• Tuberculosis and Respiratory Diseases
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• v.39 no.4
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• pp.318-324
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• 1992

Acquired tracheobronchial stenosis has resulted from vehicular accidents, prolonged tracheal intubation, sleeve resection, tuberculosis and sarcodosis. Various modalities of therapy for the relief of such stenosis included surgery, cryotherapy, laser photoresection, and sometimes balloon dilatation. Several recent reports have described the use of self-expandable metal stents for the dilatation of stenotic areas in the tracheobronchial tree. Three patients of benign acquired tracheobronchial stenosis were treated with self-expandable metal stents, who had shown little response to several times of balloon dilatations; One patient had a tracheal stenosis caused by intubation, one a right main bronchial stenosis developed after reconstructive surgery of traumatic bronchial rupture, and the other a left main bronchial stenosis caused by longstanding endobronchial tuberculosis. We found that the using stent in benign acquired tracheobronchial stenosis can be effectively performed with alleviation of clinical symptoms and lung function. And even in longstanding localized stenosis of main bronchus without distal bronchial destruction, lung perfusion also improved.

• Journal of Chest Surgery
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• v.33 no.1
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• pp.107-111
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• 2000

Although a tracheal stent can be an option for inoperable tracheal stenoses there still are some troublesome side effects including overgranulation from foreign body irritation restenosis and patient's discomfort associated with the procedure. We report a successful case of a retrievable stent made of self-expandable 'shape memory' metal and polyurethane in a 24 year old female patient with respiratory distress and tight stenosis in the trachea and left main bronchus, The stent was inserted following a balloon dilatation and was successfully removed on the 7th days after the procedure. She regained a normal active life without any repiratory symptoms and a follow-up of 8 months showed satisfactory results.

• Journal of Hospice and Palliative Care
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• v.12 no.2
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• pp.49-55
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• 2009

Self expandable metal stent (stent) implantation of upper gastrointestinal (UGI) tract is now widely accepted for the palliation of obstructive symptoms caused by inoperable malignant UGI obstruction. With the technical progress and accumulation of clinical experiences, it became possible to perform the procedure easily, safely and effectively. However, clinicians should pay attention to the post-procedural care, because early or late complications such as ulceration, pain, bleeding, food impaction, perforation, migration or in-stent tumor growth could occur. In this review, several topics about stent placement in the UGI tract are discussed, such as major indications for stenting, kinds of stents, and post-procedural management.

• Korean Journal of Radiology
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• v.22 no.5
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• pp.742-750
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• 2021

Objective: To assess the safety and clinical efficacy of percutaneous transhepatic enteral stent placement for recurrent malignant obstruction in patients with surgically altered bowel anatomy. Materials and Methods: Between July 2009 and May 2019, 36 patients (27 men and 9 women; mean age, 62.7 ± 12.0 years) underwent percutaneous transhepatic stent placement for recurrent malignant bowel obstruction after surgery. In all patients, conventional endoscopic peroral stent placement failed due to altered bowel anatomy. The stent was placed with a transhepatic approach for an afferent loop obstruction (n = 27) with a combined transhepatic and peroral approach for simultaneous stent placement in afferent and efferent loop obstruction (n = 9). Technical and clinical success, complications, stent patency, and patient survival were retrospectively evaluated. Results: The stent placement was technically successful in all patients. Clinical success was achieved in 30 patients (83.3%). Three patients required re-intervention (balloon dilatation [n = 1] and additional stent placement [n = 2] for insufficient stent expansion). Major complications included transhepatic access-related perihepatic biloma (n = 2), hepatic artery bleeding (n = 2), bowel perforation (n = 1), and sepsis (n = 1). The 3- and 12-months stent patency and patient survival rates were 91.2%, 66.5% and 78.9%, 47.9%, respectively. Conclusion: Percutaneous enteral stent placement using transhepatic access for recurrent malignant obstruction in patients with surgically altered bowel anatomy is safe and clinically efficacious. Transhepatic access is a good alternative route for afferent loop obstruction and can be combined with a peroral approach for simultaneous afferent and efferent loop obstruction.