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

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.

Percutaneous Transhepatic Biliary Drainage Using a Ligated Catheter for Recurrent Catheter Obstruction: Antireflux Technique

Percutaneous transhepatic biliary drainage (PTBD) is an established procedure for biliary obstruction. However, duodenobiliary or jejunobiliary reflux of the intestinal contents through a PTBD catheter sometimes causes recurrent catheter obstruction or cholangitis. A 64-year-old female patient with a history of choledochojejunostomy was referred to our department with acute cholangitis due to choledochojejunal anastomotic obstruction. Emergent PTBD was performed, but frequent obstructions of the catheter due to the reflux of intestinal contents complicated the post-PTBD course. We therefore introduced a catheter with an antireflux mechanism to prevent jejunobiliary reflux. A commercially available catheter was modified; side holes were made at 1 cm and 5 to 10 cm (1 cm apart) from the tip of the catheter, and the catheter was ligated with a nylon thread just proximal to the first side hole. Using this novel "antireflux PTBD technique," jejunobiliary reflux was prevented successfully, resulting in a longer patency of the catheter.