Endoscopic Ultrasound-guided Drainage of Walled Off Necrosis (WON)

Study Overview
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Brief Summary
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The purpose of this study is to compare the effect of lumen-apposing metal stent (LAMS) and double pigtail plastic stents (DPPSs) on the drainage of pancreatic walled-off necrosis (WON), mainly to observe the efficacy and safety of LAMS for WON.

Detailed Description
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Patient with pancreatic walled-off necrosis (WON) would be treated randomized with lumen-apposing metal stent (LAMS) or double pigtail plastic stents (DPPSs) under the guidance of Endoscopic Ultrasonography. The investigators compare the effect of the two stents, including technical success, clinical success, adverse event, recurrence, and so on.

Official Title
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Endoscopic Ultrasound-guided Drainage of Walled Off Necrosis (WON)

Conditions
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Pancreatic Pseudocyst

Intervention / Treatment
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* Device: Lumen-apposing metal stent (LAMS)
* Device: Double pigtail plastic stent (DPPS)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject with ages from 18-80 years old Subject with pancreatic pseudocysts confirmed by CT Subject with a history of MSAP or SAP, the pseudocysts were formed more than 3 months The size of pseudocyst is more than 6 cm, and the cyst adjacent to the gastric wall Subject has the symptoms related with the pseudocyst The consent form has been signed Exclusion Criteria: Subject is younger than 18 years or older than 80 years Pancreatic pseudocyst communicate with the main pancreatic duct Subject can't accept the endoscopic procedure Pancreatic pseudocyst with infection or subject diagnosed with pancreatic abscess The distance between gastric and the wall of the pseudocyst is more than 1 cm Subject with 2 or more than 2 cysts Subject has blood coagulation dysfunction Pregnant or subject has mental disorders

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Lumen-apposing metal stent(LAMS)<br>Lumen-apposing metal stent(LAMS) will be deployed by endoscopist under the guidance of EUS | Device: Lumen-apposing metal stent (LAMS)<br>* Endoscopic Ultrasound-guided Drainage of WON with LAMS<br>|
| Active Comparator: Double pigtail plastic stent(DPPS)<br>Double pigtail plastic stent(DPPS) will be deployed by endoscopist under the guidance of EUS | Device: Double pigtail plastic stent (DPPS)<br>* Endoscopic Ultrasound-guided Drainage of WON with DPPS<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| clinical success | The cysts completely disappeared, or diameter ≤ 2cm in the imaging follow-up symptoms have eased | uo to 1 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| adverse event | any adverse event occured after stent inserted | up to 2months/ stent remove | 
| recurrence rate | After the clinical success, imaging examination show cyst again and accompanied by symptoms | up to 12 months | 
| technical success | Stent placed through the wall bracket and pancreatic pseudocyst successfully | up to 48 hours |