What is a colonoscopy?
Colonoscopy is a frequently performed examination in internal medicine, during which the physician examines the inside of the intestine. A distinction is made between small bowel endoscopy (enteroscopy) and large bowel endoscopy (colonoscopy). Endoscopic examination of the rectum alone (rectoscopy) is also possible.
Further information: Rectoscopy
You can read about how endoscopy of the rectum works and when it is performed in the article Rectoscopy.
While the large intestine can be easily viewed with a tube-shaped instrument, an endoscope (also called a colonoscope), the small intestine is more difficult to reach. The physician can assess the upper small intestine behind the stomach outlet, the duodenum, in the course of an extended gastroscopy (gastroduodenoscopy); for deeper sections, he now uses the so-called capsule endoscopy.
When is a colonoscopy performed?
- Colorectal cancer and its precursors (e.g. polyps)
- Protrusions of the intestinal wall (diverticula) or inflamed diverticula (diverticulitis)
- Chronic inflammatory bowel diseases (for example Crohn’s disease or ulcerative colitis)
- acute inflammation or circulatory disorders of the intestinal wall
In case of intestinal obstruction, known acute diverticulitis or peritonitis, colonoscopy must not be performed!
Colonoscopy: Screening in Germany
Early detection of colorectal cancer is a common and particularly important reason for a colonoscopy: the earlier a tumor is detected in the intestine, the better the chances of cure. Even without symptoms, patients with health insurance are entitled to a preventive colonoscopy: women from the age of 55, men from the age of 50. The costs are covered by statutory or private health insurance.
Experts recommend that everyone over the age of 50 be screened for colorectal cancer. What women, for example, can do before their first colonoscopy, you can read in our article “Colorectal cancer screening”.
Screening colonoscopy: How often is it necessary?
Experts recommend the first colonoscopy for men at age 50 and women at age 55, provided there is no known increased risk of colorectal cancer. If the findings are unremarkable, a repeat colonoscopy after ten years is sufficient. If the doctor finds abnormalities such as polyps during the colonoscopy, closer monitoring is often necessary.
What is done during a colonoscopy?
In order for the doctor to see something during the colonoscopy, some preparations are necessary the day before. This includes, among other things, cleaning the intestines. Immediately before the procedure, anxious patients can be given a sedative if they wish.
Further information: Colonoscopy: preparation
You can read about the measures the patient should take to prepare for the colonoscopy in the article Colonoscopy: Preparation.
Colonoscopy (coloscopy)
- Ileocolonoscopy (additional assessment of the ileum)
- high colonoscopy (assessment of the entire colon up to the appendix)
- sigmoidoscopy (assessment of the sigmoid colon, a part of the large intestine)
- partial colonoscopy (assessment of the lower colon)
If necessary, he or she will use the instrument to take small samples, known as biopsies, from the intestinal wall, which are then examined in the laboratory.
As an alternative to the classic colonoscopy with an endoscope, virtual colonoscopy, also known as CT colonoscopy, is also available. In this examination, a computer tomograph produces images of the intestine. The colon is inflated with air so that it can be seen clearly.
Small intestine endoscopy (capsule endoscopy and balloon endoscopy)
Because of its length and many coils, it is difficult to assess the entire small intestine with an endoscope. A relatively new procedure that solves this problem is called capsule endoscopy. In this, the patient swallows a tiny video capsule that passes through the intestine via the stomach and takes pictures of its inner workings. It transmits the images live by radio to a receiver that the patient carries with him.
Further information: Colonoscopy: Procedure
You can read about the exact procedure for colonoscopy of the small intestine and large intestine in the article Colonoscopy: Procedure.
For colonoscopy in children, the gastroenterologist uses a special pediatric endoscope. This comes in different sizes with diameters ranging from five to thirteen millimeters, depending on the child’s body size. In addition, children usually receive general anesthesia or a strong sedative medication for the colonoscopy.
What are the risks of a colonoscopy?
Risks that the doctor must inform the patient about are bleeding and the rare puncture of the intestinal wall with the endoscope. Due to the short anesthesia, there may also be intolerance reactions and cardiovascular problems. In general, however, it is a very safe examination method in which complications rarely occur.
Fear of colonoscopy: What to do?
What do I need to be aware of after a colonoscopy?
If you were given a sedative during the examination, your ability to react will usually be significantly impaired for some time after the colonoscopy. Therefore, you must not actively participate in traffic on the day of the examination – neither by car nor by bicycle or on foot.
After a colonoscopy during which you have received sleeping pills, painkillers or sedatives, have an escort or cab service take you home!
As a rule, you must inform the practice before the examination who will pick you up. If you are going to be picked up by a taxi service, it is best to contact your health insurance company to find out if they will cover the costs.
Also, operating machinery or performing similar potentially dangerous activities is off-limits. You will probably still feel somewhat exhausted after a colonoscopy without short anesthesia. So it is best to have an escort pick you up in these cases as well.
Eating after colonoscopy: What is allowed?
Complaints after colonoscopy: What should I watch out for?
Diarrhea after colonoscopy is a common side effect, as the laxatives previously taken can continue to have an effect for several days. Because a lot of air enters the intestine during the examination, flatulence and increased air leakage may also occur. This is normal and no cause for alarm.
Severe pain after colonoscopy of the large or small intestine, on the other hand, is a warning signal that you should not ignore. Also, if you experience fever, sweating, severe dizziness, nausea, bleeding from the bowel or abdominal pain after colonoscopy, consult your doctor so that he or she can react quickly.
