Colonoscopy is the standard investigation that explores the rectum and colon directly and in real time with the help of a colonoscope, a flexible instrument equipped with a video camera and light source, connected to a video system provided with a screen on which the images are viewed. The instrument has a working channel through which it can be inserted various endoscopic accessories necessary for the special diagnostic manoeuvres (biopsies) and therapeutic (polypectomies), submucosal injections of certain substances, applications of haemostatic clips, dilation of stenosed anastomoses.
Nowadays a routine procedure, colonoscopy is part of the package of investigations for colon disorders: polyps, tumours, haemorrhagic lesions, diverticula, inflammatory diseases.
Colonoscopy can be performed for diagnostic purposes (with or without tissue biopsy sampling), or for interventional purposes (for example, in the case of polypectomy or dilation of anastomoses). The screening for early detection of rectal cancer is made after the age of 50 or earlier in the case of patients with a family history of colon cancer; in the case of patients with colon cancer, during the periodic oncological checks, the colonoscopy allows for the early identification of a relapse or the tumours appearing on the remaining colon.
Identification and removal of colonic polyps known as preneoplastic lesions represents a method of colon cancer prophylaxis and is one of the goals of colonoscopy.
In special situations, colonoscopy (for diagnostic, but especially therapeutically) can be performed in the operating room (only colonoscopy or colonoscopy as a stage in a complex surgery).
The main symptoms that will indicate the necessity of the colonoscopy examination are constipation (chronic or recently installed), chronic diarrhoea, abdominal pain, lower digestive bleeding, both obvious (blood-stained faeces - haematochezia) as well as occult bleeding (detected by specific faeces sample). Haemorrhoids and anal fissures, common disorders, require, besides the local proctologic examination, a colonoscopy for a complete diagnosis and detection of any associated lesions. Colonoscopy is also part of the investigations group indicated in patients with iron-deficiency anaemia (iron deficiency).
For an optimum colonoscopy, it is mandatory the complete evacuation of the colon one day before the procedure. The correct preparation allows for a good visualization of the entire colonic mucosa with the detection of all the lesions, even if they are of small size and offer favourable local conditions for the therapeutic manoeuvres. At the same time, a good preparation increases the patient's comfort during the examination.
Getting ready for colonoscopy involves certain dietary restrictions and the consumption of purgative solutions that result in complete evacuation of the colon until the removal of aqueous and clear faeces. There are several formulas for getting ready for colonoscopy and the instructions of the endoscopy physician who will perform the procedure must be strictly followed. The cardiology medication will not be interrupted, it will be administered with a small amount of water; treatment with antiaggregants (Aspirin / Aspenter, Clopidogrel / Plavix) or with anticoagulants (Sintrom, Thrombostop) will be indicated during the appointment for colonoscopy because some modifications of this treatment may be necessary, according to the advice of the cardiologist. The diabetic patient (undergoing oral antidiabetic treatment or insulin treatment) should be advised that the lack of food intake during preparation for colonoscopy requires dose adjustment or temporary discontinuation of antidiabetic medication in order to prevent hypoglycaemia.
Before the procedure, the endoscopy physician explains the investigation technique to the patient, responds to any questions and concerns and the patient signs the information consent.
The result of the exploration can be communicated to the patient immediately after the investigation, while the result of the biopsy can be found at different time intervals depending on the working technique in the pathological anatomy laboratory.
With a patient who understood investigation technique, with a good collaboration between the patient- and the endoscopy team and with an adequate colon preparation, colonoscopy becomes a common, well tolerated and accepted procedure.
There is a great variability of the individual tolerance related to distension and pain, large variations of the colon anatomy, history of abdominal surgery that can change the position of the colon and there are also very anxious patients. In many of these situations, the colonoscopy with sedation can be performed, with intravenous injection of a sedative that causes tranquillity, calms anxiety, diminishes the sensations produced by colonoscopy, induces drowsiness, but which prevents the doctor-patient communication and makes it difficult to change the position. After sedation, the patient comes to his/her sense completely within 30-60 minutes, he/she is not allowed to drive the car or make important decisions and he/she must come attended as a degree of drowsiness persists after the procedure.
With or without sedation, colonoscopy with its specific indications has become a routine and absolutely necessary investigation in many situations.
