Colonoscopy is an endoscopic examination, ie an examination that allows you to see the inside of the body. Specifically, colonoscopy allows you to view the inside of the colon and rectum, to identify any abnormalities, such as inflamed tracts, polyps or tumors. To visualize the inside of the body, a suitable instrument is clearly needed. In the case of colonoscopy, this instrument is called a colonoscope; it is a probe, a thin long and flexible tube, equipped with a light at the end and an optical system to transmit the images on a special monitor. The colonoscope is inserted gently through the anus and progressively advanced along the rectum and the large intestine. I remind you briefly that the large intestine is the last part of the digestive system. Its appearance is that of a tube that starts from the cecum, continues in the colon, ends in the rectum and opens to the "external through the anus. The main function of the large intestine is to reabsorb mineral salts and water from the stool, in addition to the vitamins produced by the local bacterial flora. Large intestine and colon are therefore not exactly synonymous, even if the latter occupies most of the large intestine. . Colonoscopy is first of all a diagnostic test, because it allows to clarify the nature of symptoms attributable to diseases of the colon and rectum. At the same time, however, colonoscopy also allows to perform biopsies, that is to take small fragments of tissue to be sent to the laboratory for microscopic analysis. In addition, colonoscopy allows you to perform minor surgical interventions, such as the removal of an intestinal polyp. Intestinal polyps are growths, similar to small cauliflowers, which develop on the bowel wall, especially in the colorectal. Although these lesions are mostly benign in nature, some of them can slowly evolve into a malignant tumor. Colonoscopy, being able to identify many of these precancerous lesions, is particularly useful in a preventive perspective; in particular, together with rectosigmoidoscopy and the search for occult blood in the faeces, it is one of the possible screening tests for colorectal cancer.
Colonoscopy therefore consists in the introduction of a thin flexible instrument, called a "colonoscope", through the anus. At its end, this instrument is equipped with a light source and a micro camera, which shows the inside of the colon in real time. The colonoscope is slowly moved up the colon, starting from the rectum, and the advancement can be manual or robotic in the most recent models. During the examination, air is blown through the instrument, in order to stretch the colon walls and better explore the intestine. The colonoscopy usually lasts 15-45 minutes and takes place with a minimum of sedation, which allows the patient to withstand the examination better while remaining conscious Any discomfort can be determined above all by the introduction of air through the colonoscope, which can cause abdominal cramps and the need to "evacuate".
But what exactly is colonoscopy for? By looking at the images provided by the microcamera, the doctor can ascertain the true nature of suspected intestinal disorders, such as, for example, abdominal pain not otherwise explained, sudden constipation, long-lasting diarrhea, significant weight loss and visible blood loss in the stool. Colonoscopy makes it possible to appreciate inflammation, ulceration, diverticula, vascular anomalies, narrowing, polyps and neoplasms. If necessary, it also allows you to take biopsy samples of the mucosa, thanks to small forceps introduced through the endoscope. The samples thus taken will then be sent to the laboratory to be studied under the microscope; in this way they will help the doctor in the diagnosis of inflammatory bowel diseases and in ascertaining the benign or malignant nature of a suspected lesion. In addition to this important diagnostic role, colonoscopy can also become therapeutic. removal of any intestinal polyps using a technique called polypectomy. Typically, a special electric scalpel, in the shape of a loop, is passed through the polyp, in order to burn it at the base. The polyp will then be examined in the laboratory to determine if it is benign or malignant. In some cases, colonoscopy is therefore able to avoid a subsequent surgery; other times it allows instead to establish, with greater precision, the therapeutic path to follow. Colonoscopy is therefore an extremely useful test in the prevention of colon cancer. In fact, as a rule, it is recommended to perform a colonoscopy as a form of prevention after the age of 50. blems, it is possible to repeat the exam every 5-10 years. Alternatively, again from the age of 50, the search for occult blood in the faeces can be performed once a year, performing a colonoscopy only in the case of positivity.
For many people, the most annoying part of the colonoscopy is not so much the examination itself, but the preparation. For the result of the examination to be reliable, the intestine must be completely empty and clean. Since any faecal residues would cover the mucosa hiding its alterations, colon cleansing is nothing short of essential. In this regard, there is a specific preparation, which is indicated when booking the exam. First of all, a diet is suggested to be followed generally in the 2/3 days preceding the colonoscopy; this diet provides above all the removal of foods rich in fiber, such as fruit, vegetables and whole foods. The day before, only liquids should be taken, to be associated with the purgative. The latter generally consists of a liquid preparation that stimulates bowel movement and allows colon cleansing of stool residues. In some cases, the intake of other laxative preparations or an enema may be required.
After the end of the examination, the patient is discharged within an hour. If polyps have been removed, however, an observation period of a few hours may be necessary. After discharge, if the colonoscopy was performed under sedation, it is clearly not recommended to drive the car back to your home; better to be accompanied or use public transport. In addition, the patient should avoid performing other potentially dangerous activities in the following hours, such as driving machinery or other activities that require special attention. Minor discomforts may also persist after colonoscopy, such as gas or mild intestinal spasms.
Although colonoscopy is a fairly safe procedure, it is not immune to complications and it is right to be aware of the risks involved. The most serious complication, fortunately very rare, concerns intestinal perforation. In practice, the doctor can accidentally break the intestinal wall with the colonoscope; in these cases, immediate repair surgery is required. Another less serious complication is linked to biopsies or polypectomies. These procedures can in fact cause bleeding, which can be stopped already during colonoscopy. There is also the risk of unwanted reactions to drugs administered for sedation. For this reason, any allergies or pharmacological treatments in progress should be reported to the doctor before starting the examination Finally, some predisposed patients may have cardio-respiratory or infectious complications.
In this video we talked about traditional colonoscopy, but there is no shortage of more modern alternatives. The best known is the so-called virtual colonoscopy. This exam uses low doses of X-rays to reproduce three-dimensional images of the colon, representing its interior. Compared to the traditional method, the accuracy of the virtual colonoscopy is slightly lower.However, it has the advantage that no endoscopic probe is introduced into the rectum, but only a small cannula to insufflate the air; the examination is therefore better accepted by the patient. The main disadvantage of this technique is that it can only be used as a diagnostic tool; therefore it does not allow to perform biopsies or remove intestinal polyps, for which it is necessary to resort to the traditional technique.
