Endoscopy is a procedure in which an instrument (the endoscope) is introduced into the body through a natural orifice (like mouth or anus). The endoscope is a flexible tube with a video system that transmits and captures images and videos to a screen for viewing. This allows the specialist to see a clear detailed view of the digestive tract from the inside. The doctor that specializes in endoscopy is a gastroenterologist. Endoscopy is usually performed in a dedicated purpose built Endoscopy Center, or in an operating theater.


Purpose of Endoscopy

The purpose of the endoscopy to examine the inside of our digestive tract and to perform biopsy. This allows the doctor to diagnose the cause of symptoms and hence to recommend the appropriate treatment Endoscopy can also be used to directly carry out treatment, avoiding the need for unnecessary surgery.

Types Of Digestive Endoscopy

There are many types of endoscopy, which cater to all parts of the digestive tract. The types of digestive endoscopy can be divided into 2 groups: general or standard endoscopy, and advanced endoscopy

General endoscopy constitutes the majority of endoscopic procedures, and comprises of endoscopy of the upper gastrointestinal tract and the colon. Gastroenterologist are trained in general endoscopy, which helps them to evaluate most digestive symptoms and recommend treatment. Gastroscopy and colonoscopy are also used to screen for common digestive cancers such as stomach and colorectal cancer. If any polyps are found, they can usually be removed with standard polypectomy techniques. Some specialist would also be able to would also perform piles ligation and foreign body removal. Only the more seasoned gastroenterologist are comfortable with dealing with emergency bleeding in the digestive system using techniques like thermocoagulation, clip application, injection and ligation with bands.

1. Gastroscopy

Gastroscopy is used to examine the inside the esophagus, stomach and first part of the small intestine (duodenum). It is sometimes referred to as an upper gastrointestinal (GI) endoscopy or oesophagogastroduodenoscopy (OGD). It is used to investigate upper gastrointestinal symptoms such as epigastric pain and heartburn.

2. Colonoscopy

Colonoscopy is used to examine the inside of the colon or large intestine. It can also reach the last part of the small intestine. It is used to investigate lower gastrointestinal symptoms such abdominal pain, change of bowel habit and blood in stool. It is also the most important tool for colorectal cancer screening and prevention, where it can detect and remove precancerous polyps.

3. Polypectomy

During gastroscopy and colonoscopy, sometimes polyps are found. Polyps are benign growths that sometimes have potential to become cancer with time. The removal of polyps through endoscopy using specialized tool is called polypectomy. Special techniques may be needed to remove the polyps properly and to prevent complications.

4. Feeding Tubes

Supplemental tube feeding may be essential to provide nutrition to patients in patients who cannot swallow. The most commonly used feeding tube is a standard nasogastric tube, which can be easily inserted by the bedside and is suitable for short term feeding. Endoscopically placed feeding tubes may be helpful in the following situations:

  • Gastroscopy placed nasogastric tube: A gastroscope may be required to insert a nasogastric tube in situations where bedside placement is not possible; for example in patients with narrowing or blockage of the esophagus.
  • Percutaneous gastrostomy (PEG): A large calibre feeding tube that is placed through the abdominal wall into the stomach to allow direct feeding. The PEG tube is placed with the aid of a gastroscope, but can subsequently be changed easily at the bedside.
  • Nasojejunal feeding tube (NJFT): A long tube which passes from the nose into the small intestine, bypassing the stomach altogether. This tube is useful in patients with stomach outlet obstruction, or problems with stomach emptying.
  • Percutaneous gastrostomy with jejunal feeding tube (PEG-J): This technique combines a PEG tube together with a jejunal tube that goes through the PEG tube.

5. Piles Ligation

Not an endoscopic procedure per se, this often is done after proper assessment with colonoscopy. Piles ligation is a safe and effective treatment for small to moderate sized internal piles (hemorrhoids) that are causing symptoms and do not respond to medical treatment.

6. Emergency Endoscopy

Vomiting blood or passing out large amount of fresh blood or black stool can be an emergency. This may be associated with dizziness and weakness. It can be life threatening.. The patient should be kept fasted and go to the hospital as soon as possible. Emergency endoscopy may be necessary to stop the bleeding. Endoscopic control of bleeding is highly effective, and can avoid the need for surgery.

7. Foreign Body Removal

Sometimes foreign body may be inadvertently swallowed or inserted into the anus. The removal of these foreign body is usually done through endoscopy. This can sometimes be an emergency.

8. Anesthesia & Sedation For Endoscopy

Effective sedation is essential to ensure that the patient have a good experience undergoing endoscopic examination. You will not feel or remember the endoscopy process. We also ensure that it is carried out in a safe manner with adequate monitoring.

Advanced endoscopy refers to more complicated types of endoscopy, and are associated with higher risks of complications. Oftentimes, these procedures help patients to avoid more invasive surgery. Advanced endoscopy includes endoscopy of the bile ducts and pancreatic ducts (ERCP), endoscopic ultrasound (EUS), small intestine endoscopy, complex polyp removal, endoscopic ablation, stenting and dilation. Advanced endoscopy is particularly in the management of digestive cancers, pancreatobiliary disorders, and surgical complications. It takes additional years of focused training in a high volume centre to become competent in each advanced endoscopic procedure, and quality standards are crucial to ensure safety in these higher risk procedures.

1.  Endoscopic Retrograde Cholangiopancreatograpy (ERCP)

ERCP is an advanced technique used to treat problems of the biliary and pancreatic ducts. It utilizes a special endoscope with a side mounted camera to facilitate the passage of instruments into the bile and pancreatic ducts. X-rays are then used to guide these instruments within the ducts. ERCP is most commonly used to remove bile duct stones, and to bypass blockages.

2. Endoscopic Ultrasound (EUS)

EUS is an advanced technique the combines endoscopy with ultrasound. This can obtained highly detailed images of the intestinal wall itself, as well as the adjacent organs. It is particularly useful to diagnose disorders in the intestine wall, pancreas and bile ducts. It provides a minimally invasive method to obtain tissues samples from hard to reach internal organs such as the pancreas in order to allow a diagnosis. It can also be used for nerve blocks and fluid drainage.

3. Image Enhanced Endoscopy (IEE)

These comprise of various techniques to enhance the images captured during standard endoscopy. This helps to detect and characterize certain problems which are hard to see with standard endoscopy. The techniques include: chromoendoscopy, which uses dyes to look for specific features, and equipment based IEE, which uses technology to enhance the images in multiple different ways.

4. Complex Polyp Removal Or Advanced Polypectomy

The majority of polyps found during endoscopy are simple to remove using standard polypectomy techniques. Occasional, ‘complex’ polyps may be found which are larger, flatter or located in difficult to reach areas. These polyps cannot be safely removed using standard techniques, and require more advanced techniques for safe and complete removal. These include Endoscopic Mucosal Resection (EMR) and Endoscopic Submucosal Dissection (ESD).

5. Small Intestine Endoscopy Or Enteroscopy

Enteroscopy is used to examine the inside of the small intestine, and to apply endoscopic treatment as necessary. The small intestine is long, measuring about 6 metres in length. It is also located deep from the mouth or anus, and is highly mobile. Hence, special techniques are required to examine this area. The 2 main methods are: capsule endoscopy and device assisted deep enteroscopy.

6. Dilation And Stenting

The digestive tract may be blocked or leaking due to various reasons. This can occur anywhere, from the esophagus, stomach outlet, small intestine, bile duct through to the colon. Dilation is used to ‘stretch’ a narrow segment to make it wider. Stenting is used to insert a metal tube to bypass a blockage or cover a leak. X-rays are sometimes used to help with visualizing beyond the blockage.

7. Endoscopic Ablation

Endoscopic ablation refers to various techniques to destroy the inner lining of the digestive tract through endoscopy. It can be used in various parts of the digestive tract for treatment of several conditions, including bleeding areas and precancerous areas. The more common techniques include argon plasma coagulation, and radiofrequency ablation.

8. Endoscopy In Post Surgical Anatomy And Surgical Complications

Endoscopy in surgically altered anatomy has a lower success rate and high complication rate. It should only be performed by endoscopy experts with the proper training and exposure. Almost any endoscopic procedure can be performed in any patient with a surgically altered anatomy, including advanced endoscopic procedures. Similarly, endoscopic solutions to surgical complications are a highly niche area, which can help a patient avoid repeat surgery.


Safety in Endoscopy is paramount. The specialist will normally identify the potential complications and its risk factors, and will explain how to minimize the risk. Nonetheless, complications are inherent in any medical procedure. The overall complication rate for general endoscopy is low (< 1%). Advanced endoscopic procedures may have a higher complication rate, but this is usually lower than the alternative, which is usually surgery. For patients concerned about complications, they should ask their doctor about how their complication rates compare to the industry standard, and about what they would do if they encountered each complication. Be wary of those who say they have zero complications. Such doctors may not have done sufficient numbers of endoscopy or have been selecting only simple cases to do. They may not be able to recognize or manage a complication if encountering it for the first time.

Quality Endoscopy

The biggest limitation of endoscopy is that it is highly operator dependent. This means that the quality of endoscopy varies greatly depending on the training and expertise of the doctor performing it. It is often difficult for patients to know the standard of a doctor’s endoscopy. Yet this is the most important determinant of Quality Endoscopy. The endoscopic community recognizes this, and there are several international recommendations on how patients can infer the quality of their doctor’s endoscopy.

The quality of the endoscopy may be inferred by the following:

  • Overall number of procedures performed, and number performed per year
  • Adequacy of bowel preparation (for colonoscopy)
  • Polyp or adenoma detection rate (for colonoscopy)
  • Average time to reach caecum (for colonoscopy)
  • Quality of picture/documentation
  • Complication rate of the doctor

A simple question to determine if your doctor is good: how many endoscopies has the doctor performed for his fellow doctors and nurses? Like in any industry, health care professionals usually have a better idea who to choose to perform endoscopy for themselves.

Many doctors claim to be experts. True endoscopy experts are few in number, and are highly sought after by the industry as Key Opinion Leaders, to help advance endoscopy equipment and techniques for the future, and to push the boundaries of what endoscopy can do. To determine whether a doctor is truly an expert, ask simple questions like:

  • How many live demonstrations and endoscopic workshops has the doctor performed in?
  • How many new equipment or devices has the industry invited the doctor to introduce to the country? The doctor should be able to describe the novel techniques he has pioneered.
  • How many high level complex cases has the doctor done? The doctor should be able to describe some of these complex cases.

Endoscopy benefits patients greatly in the investigation, confirmation, and treatment of various GI conditions and raise patient outcomes. Visit a clinic and consult with your doctor regarding endoscopy. A specialist in gastroenterology will also provide expert consultation and recommendation of the endoscopy procedures appropriate for your condition.

These endoscopy procedures are also available in GUTCARE in Singapore, carried out by a trained team of specialists in gastroenterology. You can contact us to find out more about endoscopy and the costs involved.