Endoscopy is the insertion of a long, thin tube directly into the body to observe an internal organ or tissue in detail. It can also be used to carry out other tasks including imaging and minor surgery.
Endoscopes are minimally invasive and can be inserted into the openings of the body such as the mouth or anus.
Alternatively, they can be inserted into small incisions, for instance, in the knee or abdomen. Surgery completed through a small incision and assisted with special instruments, such as the endoscope, is called keyhole surgery.
Because modern endoscopy has relatively few risks, delivers detailed images, and is quick to carry out, it has proven incredibly useful in many areas of medicine. Today, tens of millions of endoscopies are carried out each year.
In this article, we will explain some of the types of endoscopy, why and how they are performed, the general procedure, and any potential risks.
Fast facts on endoscopy
Here are some key points about endoscopy. More detail and supporting information is in the main article.
- Endoscopies are quick and relatively safe procedures.
- The first endoscope was designed in 1806.
- The main reasons for endoscopy are investigation, confirmation, and treatment.
- Endoscopy can be used to remove tumors or polyps from the digestive tract.
Endoscopy is useful for investigating many systems within the human body; these areas include:
- Gastrointestinal tract: esophagus, stomach, and duodenum (esophagogastroduodenoscopy), small intestine (enteroscopy), large intestine/colon (colonoscopy, sigmoidoscopy), bile duct, rectum (rectoscopy), and anus (anoscopy).
- Respiratory tract: Nose (rhinoscopy), lower respiratory tract (bronchoscopy).
- Ear: Otoscopy
- Urinary tract: Cystoscopy
- Female reproductive tract (gynoscopy): Cervix (colposcopy), uterus (hysteroscopy), fallopian tubes (falloposcopy).
- Through a small incision: Abdominal or pelvic cavity (laparoscopy), interior of a joint (arthroscopy), organs of the chest (thoracoscopy and mediastinoscopy).
What is a capsule endoscopy?
Capsule endoscopy was developed in the mid-1990s and involves a wireless camera. The camera is small enough to fit into a capsule (roughly the size of a vitamin tablet) and can, therefore, be swallowed.
As the capsule travels through the digestive tract, it takes thousands of pictures, which are transmitted to a device attached to a wearable belt.
Capsule endoscopy is used to image the small intestine, a region that is difficult to image using standard endoscopy. It is also very useful for examining the small intestinal mucosa and diagnosing Crohn's disease. The capsule usually passes through the digestive system within 24-48 hours.
This is a relatively new technique and was given FDA approval for use in the United States in 2001. To date, more than 500,000 capsule endoscopy procedures have been carried out, and nearly 1,000 articles have been published covering its clinical use.
The procedure does not require an overnight stay in the hospital and usually only takes around 1 hour to complete. The doctor will provide instructions about the preparation for the procedure.
For many types of endoscopy, the individual needs to fast for around 12 hours, though this varies based on the type.
For procedures investigating the gut, laxatives may be taken the night before to clear the system.
A doctor will carry out an examination before the endoscopy. It is important to mention all current medications (including supplements) and any previous procedures.
The procedure will depend to some extent on the reason for the endoscopy.
There are three main reasons for carrying out an endoscopy:
- Investigation: If an individual is experiencing vomiting, abdominal pain, breathing disorders, stomach ulcers, difficulty swallowing, or gastrointestinal bleeding, for example an endoscope can be used to search for a cause.
- Confirmation of a diagnosis: Endoscopy can be used to carry out a biopsy to confirm a diagnosis of cancer or other diseases.
- Treatment: an endoscope can be used to treat an illness directly; for instance, endoscopy can be used to cauterize (seal using heat) a bleeding vessel or remove a polyp.
Sometimes, endoscopy will be combined with another procedure such as an ultrasound scan. It can be used to place the ultrasound probe close to organs that can be difficult to image, such as the pancreas.
Modern endoscopes are sometimes fitted with sensitive lights that use narrow band imaging. This type of imaging uses specific blue and green wavelengths that allow the doctor to spot precancerous conditions more easily.
An endoscopy is typically performed while the patient is conscious, although sometimes the patient will receive local anesthetic (commonly an anesthetic spray to the back of the throat); often, the patient is sedated.
For endoscopy procedures involving entry through the mouth, a mouth guard will be used to protect the teeth and lips as the tube is inserted.
Endoscope use in surgery
Endoscopy has advanced in recent years, enabling some forms of surgery to be conducted using a modified endoscope; this makes the surgery less invasive.
Procedures such as the removal of the gallbladder, sealing and tying the fallopian tubes and the removal of small tumors from the digestive system or lungs are now commonplace.
A laparoscope is a modified endoscope used for keyhole surgery (also referred to as laparoscopic surgery).
Laparoscopic surgery requires only a small incision and can be used for appendectomies (removal of the appendix), hysterectomies (removal of the uterus) and prostatectomies (removal of prostate tissue).
Using this technique, patients lose less blood during and after surgery and can recover much faster compared with standard surgical procedures.
Endoscopy is a relatively safe procedure, but there are certain risks involved. Risks depend on the area that is being examined.
Risks of endoscopy may include:
- over-sedation, although sedation is not always necessary
- feeling bloated for a short time after the procedure
- mild cramping
- a numb throat for a few hours due to the use of local anesthetic
- infection of the area of investigation: this most commonly occurs when additional procedures are carried out at the same time. The infections are normally minor and treatable with a course of antibiotics
- persistent pain in the area of the endoscopy
- perforation or tear of the lining of the stomach or esophagus occurs in 1 in every 2,500-11,000 cases
- internal bleeding, usually minor and sometimes treatable by endoscopic cauterization
- complications related to preexisting conditions
Any of the following symptoms should be reported to a doctor:
- dark colored stool
- shortness of breath
- severe and persistent abdominal pain
- chest pain
- vomiting blood
Recovery will depend on the type of procedure. For an upper endoscopy, which is used to enable a doctor to examine the upper gastrointestinal tract, the patient will be observed for some time after the procedure, usually around one hour, while any sedative medication wears off.
The person should not usually work or drive for the rest of the day, because of the sedative effect of the medication used to prevent the pain.
There may be some soreness. With this type of endoscopy, there may be bloating and a sore throat, but these usually resolve quickly.