THERAPEUTIC ENDOSCOPY Your GI docs can turn their endoscopes into therapeutic devices with the latest add-on devices.

New devices that attach to endoscopes and let your GI docs not just diagnose but also treat disorders under direct visualization has spawned a new term: therapeutic endoscopy. From mapping tumors to draining cysts, these add-on devices are turning endoscopy into therapeutic care. Here's a look at a few of them.

Pancreatic Cyst Drainage
Axios Stent and Delivery System
Boston Scientific
The Axios system from Boston Scientific provides ideal treatment for patients suffering from pancreatitis, with attention to 2 pancreatic fluid collections in particular: pancreatic pseudocysts and walled-off pancreatic necrosis. The fluid that builds from an inflamed pancreas can lead to enlarged, sometimes life-threatening cysts. Surgical treatments that are available to treat these cysts include cystogastrostomy, by which a surgeon can open a connection between the pancreas and the stomach wall to drain the fluid directly through the GI tract, along with similar procedures through the small intestine or duodenum. These procedures, however, are costly and invasive and they require longer recovery times than endoscopic treatment.

The beauty of the Axios system is that the cautery-enabled catheter and the self-expanding metal stent are both combined into one device on the scope. Under direct visualization via endoscopic ultrasound (EUS), the scope is guided into the stomach and along the lumen until it reaches the target structure — in this case, the pancreas. Once there, the GI provider uses a generator and pump to charge the catheter with a high-density currency that creates a clean and precise cut in the tissue through which the catheter passes. Once the incision is made and the catheter has gained access, the metal stent is planted in the channel and self-expands to hold it open for proper drainage. Ideally, the procedure more or less creates a plumbing system without leakage.

Self-expanding metal stents have recently become more preferable to plastic stents which, although providing the same mechanism, are more limited in diameter and encourage the buildup of bacterial microfilm as a result. Metal stents boast a larger diameter, and they can be left in place for up to 6 months in some cases. The other benefit of being able to leave a metal stent in place for a longer period of time is that it allows for re-entry to treat necrosis with necrosectomy.

Enhanced ERCP
SpyGlass Direct Visualization System
Boston Scientific
This single-use piece of equipment enhances any endoscopic retrograde cholangiopancreatography (ERCP) procedure. ERCP joins endoscopy with the imaging of fluoroscopy, a combination that is best suited for viewing pancreatic and bile ducts, and the advantage of this procedure is that it allows for further therapeutic treatment. Being single-use, Boston Scientific's SpyGlass has no need for sterile reprocessing. Plus, it reduces the risk of image quality declining after continued usage, and with 4-way deflection, the SpyGlass renders high-resolution imaging that makes it simple to detect stones and strictures. These structures can then be diagnosed and treated with additional equipment under the guidance of imaging from the SpyGlass.

Since ERCP is more invasive than endoscopic ultrasound, it is typically performed exclusively with therapeutic intent. However, tools like SpyGlass and its partner devices make ERCP an appealing and effective procedure, especially with the 2nd generation of SpyGlass, which, in the last couple of years, has moved from fiber-optic imaging to clearer digital imaging. SpyGlass has 2 partner devices:

SpyBite forceps. As the name suggests, the SpyBite forceps is a device best paired with the SpyGlass during ERCP. Used as a diagnostic tool, namely for cholangiocarcinoma and pancreatic cancer, the SpyBite attaches to the endoscope along with the SpyGlass, which provides direct visualization. Once indeterminate strictures are detected, the SpyBite can retrieve tissue to take a direct biopsy. This device brings the diagnostic yield to 90% versus a 30% yield via traditional diagnostic measures, such as a wire-guided cytology brush that uses fluoroscopic imaging to conduct the biopsy. This traditional method is done under fluoroscopic guidance only and the brushings are done without direct visualization of the stricture. The digital imaging of the SpyGlass reduces room for error.

EHL and Holmium Laser. While the SpyBite is best suited to diagnose indeterminate strictures, electrohydraulic lithotripsy (EHL) and Holmium Laser lithotripsy are ideal for managing large (>1cm) stones, impacted stones that are stuck on bile walls or intrahepatic stones caught in difficult areas. Both of these technologies provide the same efficiency in breaking up and gathering stones. The only difference is that the Holmium Laser features a pointing device to aim before it executes the procedure. Here's how it works: a tiny probe, plugged into a generator, is passed down through the SpyGlass to align itself with the stone. Using the generator and pump, the provider activates the device to fragment the stones into more manageable bits to gather. At this point, traditional devices like extraction balloons and retrieval baskets are then passed down to gather the remaining pieces. With the initial help of EHL or the Holmium Laser, Boston Scientific boasts a 75% success rate in removing all stones from bile ducts.

Barrett's Esophagus
Barrx 360 Express RFA Balloon Catheter
Medtronic
This device is used to ablate Barrett's esophagus to prevent it from progressing to esophageal cancer. Guided by an endoscope, this deflated, electrode-wrapped balloon is guided by endoscopy into the esophagus along nondysplastic, eroded tissue. The balloon then self-inflates to the appropriate diameter of the esophagus, and once inflated, the attached generator provides a charge to ablate the tissue and prevent it from becoming cancerous. Without risk of physician error, the generator can control the depth of ablation up to 1,000 microns.

Before this device is deployed, however, a biopsy is conducted via upper endoscopy. This pre-exam provides a diagnosis as to where the tissue falls in terms of risk of progression to esophageal cancer. The ablation balloon is used for patients who have dysplasia (pre-cancerous cells) in the setting of Barrett's esophagus. Facilities without access to this equipment, though, may be more likely to recommend that patients who test positive for potentially cancerous cells in their esophagus undergo esophagectomy, a procedure with a high morbidity and mortality rate. The goal of radiofrequency ablation with or without endoscopic mucosal resection is to treat cases in a much less invasive manner than surgery. The procedure that this device provides is less invasive, less traumatic, less costly and less time-consuming. The entire procedure takes no more than 20 minutes and it saves lives.

Mapping Tumors
EchoTip Ultra Fiducial Needle
Cook Medical
The fiducial needle turns your endoscope into a tracking device, marking potentially malignant masses in the GI tract with fiducials, tiny gold pegs used to mark potentially cancerous masses, so that they can be easily located during radiation therapy afterward. The EchoTip is used in conjunction with cyberknife radiation oncology. Using an endoscopic ultrasound (EUS) as a guide, the fiducial needle is guided through the GI tract with up to 4 preloaded fiducials. When potentially malignant masses are identified through the endoscopic ultrasound, the physician can activate the needle to plant a fiducial within the mass. Once the masses have been marked and identified, the patient is ready to undergo cyberknife radiation that can pinpoint the fiducials to within centimeters.

Without this technology, traditional methods might also use EUS to map out tumors in the gastrointestinal system, but marking their locations is done on the outside of the body with much less precision than the fiducial needle provides. Another benefit of the fiducials is that they are made of gold, a highly non-reactive metal. Gold won't pose any threats to tissue before, during or after radiation treatment, and because of the small size of the fiducials, they can be left within the patient's body and passed naturally. OSM