Gut Liver.  2013 Nov;7(6):725-730.

A Novel, Fully Covered Laser-Cut Nitinol Stent with Antimigration Properties for Nonresectable Distal Malignant Biliary Obstruction: A Multicenter Feasibility Study

• Isayama H
• Kawakubo K
• Nakai Y
• Inoue K
• Gon C
• Matsubara
• Kogure H
• Ito Y
• Tsujino T
• Mizuno S
• Hamada T
• Uchino R
• Miyabayashi K
• Yamamoto K
• Sasaki T
• Yamamoto N
• Hirano K
• Sasahira N
• Tada M
• Koike K

Abstract

BACKGROUND/AIMS
Stent migration occurs frequently, but the prevention of complications resulting from covered self-expandable metal stents (C-SEMSs) remains unresolved. We prospectively assessed a newly developed C-SEMS, a modified covered Zeo stent (m-CZS), in terms of its antimigration effect.
METHODS
Between February 2010 and January 2011, an m-CZS was inserted into 42 patients (31 initial drainage cases and 11 reintervention cases) at a tertiary referral center and three affiliated hospitals. The laser-cut stent was flared for 1.5 cm at both ends, with a 1 cm raised bank located 1 cm in from each flared end. The main outcome of this study was the rate of stent migration, and secondary outcomes were the rate of recurrent biliary obstruction (RBO), the time to RBO, the frequencies of complications, and overall survival.
RESULTS
Of the 31 patients with initial drainage, stent migration occurred in four (12.9%, 95% confidence interval, 5.1% to 29.0%), with a mean time of 131 days. RBO occurred in 18 (58%), with a median time to RBO of 107 days. Following previous C-SEMS migration, seven of 10 patients (70%) did not experience m-CZS migration until death.
CONCLUSIONS
m-CZSs with antimigration properties effectively, although not completely, prevented stent migration after stent insertion.

Keyword

Cholestasis, extrahepatic; Stents; Cholangiography; Endoscopic retrograde

MeSH Terms

Aged
Aged, 80 and over
Alloys
Carcinoma/*complications
Cholestasis/etiology/*therapy
Digestive System Neoplasms/*complications
Drainage
Equipment Design
Feasibility Studies
Female
Humans
Kaplan-Meier Estimate
Lymphatic Metastasis
Male
Middle Aged
*Prosthesis Failure
Recurrence
Reoperation
*Stents/adverse effects
Time Factors
Alloys