A: Endoscopic treatment from the “inside” is inherently less invasive than surgery from the “outside” (through the abdomen or chest). Recovery is rapid and nearly all patients go home after the procedure and return to their normal activities and routine the following day. However, endoscopic therapy is not just about avoiding skin incisions (and scars), avoiding hospitalization, and avoiding surgical complications. Endoscopic therapy is not endoscopic surgery (duplication of what is done from the outside, but from the inside); endoscopists seek smarter solutions that restore and maximally preserve normal tissue and physiology.
Q: What is Diagnostic Endoscopy?
A: Diagnostic endoscopy is the inspection of the lining of the gastrointestinal tract utilizing an endoscope. An endoscope is a fully flexible tube with 4-way directional control of the tip. About the thickness of an ink pen, it has a tiny light and camera at the tip that allows the endoscopist to guide it under direct vision into the gastrointestinal tract, either from above (through the mouth) or below (through the anus). Advanced digital video chip technology projects high definition color images of the intestinal tract onto a monitor.
Q: What is Therapeutic Endoscopy?
A: A channel within the endoscope provides a conduit to introduce miniature instruments to the inside of the body for therapeutic procedures. Therapy can be delivered not only directly to the gastrointestinal (GI) tract itself under direct endoscopic visualization, but also to organs that surround the GI tract under ultrasound guidance. A spectrum of treatments using conventional cautery, laser, radio-frequency ablation, and argon plasma coagulation are available to accomplish the therapeutic mission. Novel treatments in development include high frequency ultrasound and gene therapy. A list of miniature instruments that enable therapeutic endoscopic procedures is shown below.
Basket, balloon, net--> Extraction
Snare --> Polypectomy
Bougie, balloon --> Dilation
Needle catheter --> Injection, cutting
Sphincterotome --> Sphincterotomy
Thermal probes--> Ablation
Bands, loops, clips--> Ligation
Stent (lwithin the lumen)---> Restore the lumen
Stemt (across lumens) —> Create an anastomosis
Q: What is Endoscopic Ultrasonography (EUS)?
A: EUS is ultrasound imaging performed from inside of the body using a specialized endoscope (“echoendoscope”) that incorporates a miniaturized ultrasound transducer at the tip. This allows the endoscopist to see beyond the lining of the gastrointestinal tract, both inside and outside the wall. Organs adjacent to the gastrointestinal tract such as the pancreas, gallbladder, bile duct, and liver are visualized with high resolution in exquisite detail. The echoendoscope has all the standard functions for diagnostic and therapeutic endoscopy. Miniature instruments can be inserted through the working channel for diagnostic and therapeutic procedures.
Q: Why Endoscopic Screening?
A: Digestive system organs include the esophagus, stomach, colon, pancreas, bile duct, gallbladder, and liver. Cancers of these organs account for more cancer deaths than any other part of the body. Colon cancer leads as the second deadliest and third most common cancer today. The incidence of esophageal cancer is growing faster than any other cancer (this is related to the rising incidence of gastrointestinal reflux disease). Pancreatic cancer - now the fourth most common cancer - is also on the rise. The cause is unknown, but exposure to a growing number of carcinogens in our food and environment are no doubt contributory.
As with most cancers, digestive system cancers are usually detected at an advanced stage when symptoms arise, such as bleeding (anemia), pain, and weight loss. Cure of cancer when advanced stage is unlikely; conventional treatments including surgery, chemotherapy, and radiation therapy may prolong survival, but come at the trade-off of burdensome side-effects that can significantly impact quality of life.
These depressing statistics can be dramatically changed with endoscopic cancer screening. In fact, if everyone underwent endoscopic screening, most digestive system cancers would be detected with the endoscope at a sufficiently early stage for cure – often delivered with the endoscope. Polypectomy of a precancerous growth in the colon is such an example of how detection at a “precancerous” stage during screening is curative, before the growth starts to invades into the colon wall and spreads to other sites (“precancerous” growth are technically cancer since they will become cancers with time). For screening of organs outside the gastrointestinal tract, such as the pancreas, bile duct and gallbladder, endoscopists use endoscopic ultrasonography (EUS) from inside the body. A tumor can be seen with EUS long before it is seen on other imaging studies such as CT or MRI scan, and long before it produces any symptoms.
Q: Is Anesthesia necessary for endoscopy?
A: The lining of the bowel has no pain receptors, hence endoscopic treatment is painless and - in theory - anesthesia is not required. However, introduction of the endoscope into the esophagus can provoke a gag reflex, and advancement through the colon can be uncomfortable. Most patients therefore chose to have anesthesia. Endoscopy is performed under deep sedation, in contrast to general anesthesia required for surgery. Deep sedation is safer with fewer side effects and quickly wears off.