1. Endoscopic examinations of the digestive tract
Endoscopic methods are based on the use of devices equipped with fiber-optic systems. This technology ensures the transmission of a clear image from the lumen of the digestive tube. The physician gains the ability to conduct a detailed visual examination of the mucous membrane at various levels of the gastrointestinal tract.
Endoscopy possesses not only diagnostic potential (including the collection of material from altered areas for histological confirmation of the diagnosis via targeted biopsy), but also broad therapeutic capabilities. Right during the examination, a specialist can remove small pathological formations, such as polyps.
Depending on the level of examination, different techniques are used:
- EGD (esophagogastroduodenoscopy): aimed at assessing the condition of the upper divisions. The flexible endoscope passes through the esophagus, stomach, and reaches the duodenum.
- Colonoscopy: allows examination of the entire colon, including the cecum. The procedure is performed using a flexible fiberscope and requires mandatory preliminary preparation (cleansing enemas).
- Sigmoidoscopy (rectosigmoidoscopy): a method for visualizing the distal sections — the rectum and sigmoid colon. Its main technical feature is the use of a rigid endoscope, which is inserted through the anus.
2. Emergency endoscopy and laparoscopy
Examinations can be performed on both a scheduled and emergency basis. Emergency endoscopy is critical in gastrointestinal bleeding: it helps to quickly locate the source (ulcer, erosion, or tumor) and immediately perform hemostasis (stopping the bleeding).
Diagnostic laparoscopy — the introduction of an endoscope directly into the abdominal cavity — is singled out separately. This allows visual inspection of internal organs from the outside and targeted biopsy of parenchymal structures (liver, spleen) or lymph nodes.
3. X-ray diagnostics
X-ray methods are divided into two main categories: non-contrast (plain) and using contrast agents.
Plain abdominal radiography This basic method typically initiates the primary examination. On a plain radiograph, the physician can visualize the contours of the kidneys (less often — the spleen), and detect calculi (stones) in the kidneys or gallbladder. The method also shows calcifications in the pancreatic tissues and phleboliths in the pelvic veins.
Plain radiography is of particular importance for diagnosing conditions grouped under the concept of "acute abdomen" (primarily intestinal obstruction). For this, radiographs are taken in standing and lying positions. The main sign of pathology is the appearance of dilated bowel segments containing gas bubbles with horizontal fluid levels.
Contrast radiography Contrast enhancement with a barium sulfate suspension is used to evaluate the internal contour of organs.
- During the examination of the upper divisions and the small intestine, barium is taken per os. The method allows the detection of narrowing or widening of the esophagus, identification of filling defects in the stomach (characteristic of a tumor), noticing mucosal ulcerations (the "niche" sign), and evaluation of changes in the relief of the small intestine.
- To study the colon, contrast is administered per rectum. This technique is called irrigoscopy (barium enema). Barium is administered using an enema.
4. Preparation for radiological examination methods
The quality of X-ray visualization directly depends on proper patient preparation. The presence of gas accumulations (flatulence) can significantly interfere with visualization and obstruct the view.
2–3 days before the contrast study, a diet excluding gas-producing foods is prescribed. The following are completely removed from the diet:
- fresh milk;
- legumes;
- cabbage and other fresh vegetables.
5. Other instrumental methods (ultrasound and CT)
To clarify the topography and structure of organs, additional visualization methods are used:
- Ultrasound examination (ultrasound). The main goal is the visualization of solid (parenchymal) organs. It allows viewing the liver, spleen, kidneys, and, less commonly, abdominal lymph nodes.
- Computed tomography (CT). Used for the most accurate assessment of the size and localization of any pathological formations in the abdominal cavity.
Briefly: answers to topical questions
What therapeutic manipulations can be performed during gastrointestinal endoscopy?
During gastrointestinal endoscopy, the following therapeutic manipulations can be performed:
- Bleeding arrest — performance of hemostasis; laser coagulation, glue application, coagulation or clipping of the bleeding vessel, endoscopic ligation, or sclerotherapy of varices are possible.
- Polyp removal — in the stomach and intestines; in early colorectal cancer, endoscopic polypectomy and endoscopic mucosal resection of the colon are possible.
- Stone removal — from the bile ducts.
- Foreign body extraction — for example, from the esophagus.
Which specific radiological sign indicates intestinal obstruction?
A specific radiological sign of intestinal obstruction is the appearance of Klauber's cups (air-fluid levels). During plain abdominal radiography, this sign is visualized as dilated loops of the intestine containing gas bubbles and characteristic horizontal fluid levels.
What are the possible complications during colonoscopy?
During colonoscopy and endoscopic interventions on the colon, the following complications are possible:
- Bowel perforation — the risk is particularly noted in acute inflammatory complications, during the coagulation of a bleeding vessel, and when minimizing air insufflation is necessary to prevent iatrogenic perforation.
- Bleeding — listed as one of the most frequent complications of endoscopic interventions.
- Pain syndrome — also refers to the most frequent complications of endoscopic interventions.
To memorize radiological signs: an ulcer destroys the wall, forming a depression (barium flows into the defect — the "niche" sign), whereas a tumor grows into the organ lumen, displacing the contrast (forming a "filling defect").
Class and exam questions
What is the main difference between colonoscopy and sigmoidoscopy?
Colonoscopy is performed with a flexible endoscope (fiberscope) and allows inspection of the entire colon up to the cecum. Sigmoidoscopy is performed with a rigid apparatus and evaluates only the rectum and sigmoid colon.
Why is a barium suspension needed in gastric radiography?
Hollow organs merge with surrounding tissues on conventional radiographs. Barium coats the mucosa, making it possible to see ulcers ("niches"), tumors (filling defects), and assess the mucosal pattern.
Which abdominal organs is ultrasound most informative for?
Ultrasound is used predominantly for examining solid parenchymal organs: the liver, spleen, and kidneys, whereas it is used less frequently for hollow structures containing gas.
What else to study on this topic
- Technique of targeted biopsy of the GI mucosa
- Methods of endoscopic hemostasis in ulcer bleeding
- Radiological signs of intestinal obstruction
- Complications and contraindications to EGD
- Differential diagnostics of filling defects and the "niche" sign
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