Interventional endoscopy allows the endoscopist to use an endoscope to perform surgical-type procedures from the inside. A channel within the endoscope provides a conduit to introduce miniature instruments to perform a variety of therapies. Utilizing multiple imaging modalities and a collection of advanced endoscopic tools, the Paul May and Frank Stein Interventional Endoscopy Center’s specialized team at California Pacific Medical Center in San Francisco is able to diagnose conditions and treat disease using techniques not available in most medical facilities. The IES team utilizes and has developed many innovative endoscopic procedures that replace the need for surgery, including the AXIOS™ lumen-apposing stent and delivery system, invented by Dr. Kenneth Binmoeller. Depending on your diagnosis, your doctor will explain your treatment options and develop a treatment plan with you that may include the following procedures.

Interventional Endoscopic Ultrasound (EUS) Procedures

• EUS-Guided Drainage of Pancreatic Fluid Collections — Pseudocysts and walled-off necroses can complicate severe attacks of pancreatitis. Drainage of the pancreatic fluid collection is accomplished through the bowel wall (transmural) under endoscopic ultrasound guidance. The AXIOS™ lumen-apposing metal stent is utilized in this procedure.
• EUS-Guided Bile Duct and Gallbladder Bypass Procedures — Internal endoscopic bypass procedures are performed to treat blockages and resultant infections of the gallbladder (cholecystoenterostomy) or the bile duct (choledochoenterostomy) using the AXIOS™ lumen-apposing metal stent.
• EUS-Guided Enteric Bypass — Blockage of the stomach or intestine can be treated by an internal endoscopic bypass procedure using the AXIOS™ lumen-apposing metal stent. The procedure involves the creation of a new connection between healthy segments of the bowel thereby “bypassing” the obstruction.

Complex Endoscopic Retrograde Cholangiopancreatography (ERCP) Procedures

• Ductoscopy — A miniature flexible endoscope is inserted into the bile and pancreatic ducts for evaluation. Ductoscopy is performed to clarify indeterminate findings and to guide interventional procedures such as tissue sampling and a treatment for stones called lithotripsy.
• Intraductal Shock-Wave Lithotripsy — Ductoscopy is performed to visually guide the fragmentation of impacted stones with electrohydraulic-generated shock waves.
• Sphincter of Oddi Manometry — During this test, a special type of catheter called a manometry catheter is introduced into the bile and pancreatic ducts to measure pressure and contractions of the sphincter of Oddi — a muscular valve that controls the flow of digestive fluids from the liver and pancreas to the first part of the small intestine. A "dysfunctional" sphincter may be the cause of biliary-type pain or recurrent attacks of pancreatitis.
• EUS-Guided Duct Access — Complex bile duct and pancreatic duct strictures may be caused by inflammatory diseases and cancers and result in ducts that are inaccessible using traditional techniques. With EUS-guided access, a needle is used to puncture the desired duct and a wire is used facilitate drainage procedures.

Complex Gastrointestinal Tract Procedures

• Coil and Cyanoacrylate Glue Treatment of Bleeding Varices — A devastating complication of portal hypertension is bleeding of dilated blood vessels in the gastrointestinal tract (called variceal bleeding) that can be fatal. The implantation of a coil followed by cyanoacrylate glue injection under EUS-guidance is a safe and effective treatment pioneered at the Paul May and Frank Stein Interventional Endoscopy Center.
• Endoscopic Mucosal Resection (EMR) and Submucosal Dissection (ESD) — EMR and ESD are different techniques used to curatively remove the mucosal layer of the gastrointestinal tract (esophagus, stomach and colon) that contains a precancerous or cancerous growth. EMR is used for the removal of large and/or flat polyps in the colon.
• Resection of Large or Flat Colorectal Polyps — Polyps that cannot be removed using conventional techniques require advanced EMR and ESD techniques. The precancerous growth is dissected out of the bowel wall using highly discriminating optics and instruments (referred to as “partial thickness resection”). 
• Zenker's Diverticulum Septomyotomy — A Zenker’s diverticulum is an abnormal pouch that can develop above the upper sphincter of the esophagus, interfering with swallowing and placing patients at risk of aspirating food into their airway. Septomyotomy involves creating a submucosal tunnel in the upper pharynx with special dissecting knives to safely reach and incise the cricopharyngeal muscle that causes swallowing problems.
• Peroral Endoscopic Myotomy (POEM) — The POEM procedure involves creating a submucosal tunnel in the wall of the esophagus with special dissecting knives to safely reach and incise the abnormal lower esophageal sphincter and muscle layers that cause swallowing problems.

Ongoing Clinical Research

The team at the Paul May and Frank Stein Interventional Endoscopy Center at CPMC continues to innovate new procedures and have published multiple papers on their extensive contributions to Interventional Endoscopy.