nitinol and Cholecystitis

Covered self-expandable metal stents (SEMSs) are increasingly used as alternatives to uncovered SEMSs for the palliation of inoperable malignant distal biliary obstruction to counteract tumor ingrowth. We aimed to compare the outcomes of partially covered and uncovered SEMSs with identical mesh structures and anti-migration properties, such as low axial force and flared ends.. One hundred and three patients who were diagnosed with inoperable malignant distal biliary obstruction between January 2006 and August 2013 were randomly assigned to either the partially covered (n = 51) or uncovered (n = 52) SEMS group.. There were no significant differences in the cumulative stent patency, overall patient survival, stent dysfunction-free survival and overall adverse events, including pancreatitis and cholecystitis, between the two groups. Compared to the uncovered group, stent migration (5.9% vs. 0%, p = 0.118) and tumor overgrowth (7.8% vs. 1.9%, p = 0.205) were non-significantly more frequent in the partially covered group, whereas tumor ingrowth showed a significantly higher incidence in the uncovered group (5.9% vs. 19.2%, p = 0.041). Stent migration in the partially covered group occurred only in patients with short stenosis of the utmost distal bile duct (two in ampullary cancer, one in bile duct cancer), and did not occur in any patients with pancreatic cancer.. For the palliation of malignant distal biliary obstruction, endoscopic placement of partially covered SEMSs with anti-migration designs and identical mesh structures to uncovered SEMSs failed to prolong cumulative stent patency or reduce stent migration.

Topics: Aged; Alloys; Bile Duct Neoplasms; Cholecystitis; Endoscopes, Gastrointestinal; Female; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Palliative Care; Pancreatitis; Postoperative Complications; Proportional Hazards Models; Prospective Studies; Republic of Korea; Stents; Treatment Outcome

The usefulness of bilateral stent placement for malignant hilar obstruction is still under debate. Nevertheless, many endoscopists advocate the placement of an endoscopic bilateral metal stent using various new devices and techniques.. We compared the technical and clinical efficacy, and the short-term and long-term complications of the 'stent-in-stent' method using a Y-stent for malignant hilar obstruction between the early and the late period of this study.. Ninety-seven patients treated with Y-stent implantation for malignant hilar obstruction were enrolled retrospectively. In 31 patients treated during the early period, bilateral Y-configured metal stents were placed for malignant hilar obstruction using the older designed Y-stent and a closed-cell second stent. The newly designed Y-stent and a slimmer open-cell second stent were introduced in 66 patients treated during the late period. New techniques learned through experience were gradually applied throughout the entire study period.. The rate of successful placement of bilateral stents was significantly higher in patients treated during the late period than those treated during the early period (58.1 vs. 87%; P=0.001). The functional success rate was 97.3%, with no difference between the early and the late periods. Cholangitis occurred as an early complication more frequently during the early period than during the late period (16.1 vs. 1.5%; P=0.012). Cholecystitis as a late complication occurred in 21 of 76 patients (27.6%). The incidence of late complications was similar between the early and the late periods.. With the development of new devices and increased technical experience, there were better outcomes during the late period compared with the early period. Endoscopic bilateral metal stenting using a Y-stent is an attractive option for the palliative treatment of malignant hilar obstruction.

Topics: Adult; Aged; Aged, 80 and over; Alloys; Chi-Square Distribution; Cholangiopancreatography, Endoscopic Retrograde; Cholangitis; Cholecystitis; Cholestasis; Digestive System Neoplasms; Drainage; Female; Humans; Incidence; Kaplan-Meier Estimate; Male; Middle Aged; Palliative Care; Prosthesis Design; Republic of Korea; Retrospective Studies; Sphincterotomy, Endoscopic; Stents; Time Factors; Treatment Outcome