Colonoscopy is the most reliable screening test to highlight possible lesions in the colon. Another advantage is that the detected lesions can be partially or removed during the examination for analysis.
Colonoscopy consists of the exploration of the colon and rectum to detect abnormalities of the cancerous origin or not. Commonly practiced, it can be prescribed in case of unexplained intestinal symptoms (pain, diarrhea), intestinal bleeding (traces of blood in the stool), family or personal history of colorectal cancer, as well as for all people over 50 years without any particular predisposition.
Abnormalities detected during a colonoscopy may be an overgrowth of tissue called polyps, diverticula (hernias), the presence of abnormal-looking smooth tissue, or inflammation. The analysis of the samples under the microscope will make it possible to make the diagnosis. The presence of abnormalities does not necessarily indicate that it is cancer, the majority of polyps being benign; nevertheless, their elimination helps to prevent the onset of the disease.
What is a colonoscopy?
Colonoscopy is a medical imaging examination that visualizes the inner lining of the colon using an instrument called a “colonoscopy”.
This consists of a thin and flexible tube 1.5 to 2 m long connected to optical fibers or a miniature camera, and a light source. The assembly is connected to a monitor allowing direct and precise visualization during the examination. In addition, it is possible to insert instruments, forceps, or electrocautery, into the endoscope; this makes it possible to take samples (biopsies) or even total removal of the lesions or polyps (polypectomy). The tissues removed will then be analyzed under a microscope in the laboratory.
How to prepare for a colonoscopy?
Colonoscopy is an examination that in most cases takes place under general anesthesia. Also, it is imperative to consult an anesthesiologist at least 3 days before the examination.
To perform the examination, the colon, normally filled with stool, must be cleaned so that the walls can be visualized. The preparation will begin with an adapted diet to be put in place 3 days before the examination.
It will consist of a diet without fruits or vegetables (a diet without fiber or residue). To empty the colon, a laxative in liquid form should be taken the day before the examination. It is advisable to drink it very cold to reduce the salty taste.
On the day itself, due to the general anesthesia, you must be fasting. From midnight the day before the exam, do not eat or drink and do not smoke.
In addition, before the examination, you must take a shower, carefully soaping your entire body with an antiseptic solution. Colonoscopy is the most reliable screening test to highlight possible lesions in the colon. Another advantage is that the detected lesions can be partially or removed during the examination for analysis.
It should be known that the laxative can modify the action and/or the absorption of certain medicinal treatments, in particular the contraceptive pill. It is, therefore, necessary to inform your doctor of any treatment in progress before examining by colonoscopy, in particular aspirin or anticoagulants.
Good preparation before the colonoscopy is essential for the smooth running of the examination. Indeed, if the colon is not sufficiently clean, the examination can be interrupted and postponed.
How is a colonoscopy examination performed?
Colonoscopy is a generally quick examination of about 30 minutes. It is usually painless, nevertheless sometimes uncomfortable. For these reasons, it is performed in 95% of cases under general anesthesia. It can also be practiced only under painkillers according to the patient’s requests or medical contraindications.
Once under general anesthesia, the colonoscope is introduced through the anus and then gradually brought to the colon. To smooth out the tissues, the colon is inflated with air, thus allowing good visualization of all the walls. As the colonoscope progresses, images are directly transmitted and analyzed by the gastroenterologist. If abnormalities are detected, a tissue sample is taken for further analysis (biopsy). It is also possible that all of the abnormal tissue will be removed ( ablation ).
And after the exam?
When you wake up, the exam is over. The gastroenterologist then makes a report of what has been observed. The results of the analyzes performed on any biopsies will be sent to the attending physician as soon as possible.
Most of the time, after a short observation period of a few hours, it is possible to return home. Due to the use of painkillers or general anesthesia, it is recommended to be accompanied (by a relative, by public transport, or by taxi).
In some cases, a short hospital stay may be necessary, especially in the event of difficult examinations or the removal of large polyps.
It is possible to resume a normal diet and activity after the examination.
Colonoscopy can cause some side effects. Mild abdominal cramps are commonly felt. It is also normal to pass gas which corresponds to the air blown into the bowel during the examination.
What are the results of a colonoscopy?
The results of the analysis are communicated by the attending physician.
- If the colonoscopy revealed the presence of benign polyps and these could not be completely removed, further surgery will be necessary. It may be a removal of the portion of the intestine where these polyps are located ( partial resection of the intestine ). The frequency of control colonoscopies is then increased.
- If the results indicate the presence of pathology (diverticulosis, inflammatory diseases, cancer of the colon or rectum, bleeding, etc.), other examinations may be prescribed. A more complete therapeutic management is then put in place.
- If no anomaly is detected, it is then advisable to carry out a new check-up after 10 years following a discussion with your doctor.