Computed tomography (CT) of the abdominal organs

Computed tomography of the abdominal organs is a method of examining internal organs, often used in modern medicine. CT examination appeared in the diagnostic field relatively recently, in the 70s of the 20th century. It is based on the principle of the penetrating power of X-rays. The discovery of X-ray radiation occurred at the end of the 19th century, after which mathematical and technical research gradually led scientists to develop the possibility of scanning the human body with X-rays, and converting the information received into material carriers. The first commercial tomography machines were developed in 1971. Since that time, the technique of computed tomography has been improved every year.

What is a CT scan of the abdominal cavity, what is it prescribed for?

Timely diagnosis of the disease works as one of the main factors in the success of the fight against it. To do this, doctors have a whole range of different examination tools and techniques in their arsenal, for example, ultrasound, magnetic resonance and computed tomography. The latter is considered more accurate and deeper than ultrasound, and at the same time it costs less than MRI, so doctors usually prefer it when it is necessary to obtain data not only on the size and location of the organ, but also on the internal structure of deep tissues, cavities, formations.

The essence of the survey is that X-rays, penetrating the human body, allow you to get a layered image of the tissues of the organ in increments of 0,5 to 10 millimeters. The information displayed on the tomograph monitor makes it possible to display a three-dimensional picture of a particular organ.

In some cases, the doctor prescribes a CT scan with contrast – for this, a special preparation is injected into the patient after the scan, a re-scan is performed, after which the structure and structure of organs is visualized on the monitor and in the pictures in great detail.

CT scan of the abdominal cavity provides an image of each organ in the section, while the picture is not superimposed on one another. A computed tomogram shows the presence of diseases of the gastrointestinal tract and retroperitoneal space, such as: cancerous tumors, stones, foreign bodies, injuries, cystic formations.

Indications and prohibitions for computed tomography

Considering that the implementation of tomography is directly related to the need to irradiate the body, such a procedure is carried out only as directed by a doctor in cases where there is an objective need for this.

Indications for CT scan of the abdominal cavity are:

• determination of the need for surgical intervention or an already scheduled operation: this is how the doctor receives the most accurate data on the degree of organ changes and the localization of such changes;
• the appearance of acute pain, jaundice, sudden weight loss of unknown etiology;
• disruption of the urinary system;
• disorder of the digestive process;
• suspicion of the presence of neoplasms;
• manifestation of liver disease;
• suspicion of vascular disorders;
• control over the prescribed treatment;
• the appearance of symptoms of damage to the lymph nodes.

Some conditions and pathologies in humans completely exclude the possibility of examining the abdominal organs using a computed tomograph. For example, during pregnancy and during breastfeeding, X-ray exposure is categorically not recommended – it can harm the child.

Some tomographs have a patient weight limit of up to 140-180 kilograms. If the body weight exceeds this mark, the implementation of the procedure may be in question.

Conducting CT of the abdominal organs, however, as well as other parts of the body and organs, is prohibited for patients whose age has not reached 3 years. Children of primary school age can be scanned using a tomograph, however, if possible, it is better to replace this research method with more harmless ones, such as MRI.

Diseases such as diabetes mellitus, acute inflammation of the kidneys, heart, liver, blood are considered relative contraindications when conducting a study with a contrast agent – if they are present, the doctor at his own discretion decides whether the procedure is possible.

As for computed tomography with contrast, its contraindications, also associated with the introduction of a contrast agent, are:

• diagnosed in the patient intolerance to iodine and iodine-containing drugs;
• a history of allergies or severe bronchial asthma;
• hyperthyroidism;
• diagnosed renal or hepatic insufficiency in any form.

Preparing for an Abdominal CT Scan

For this type of examination, doctors put forward a number of special requirements regarding nutrition, since the organs of the digestive tract are scanned in the process.

Already a few days before the planned tomography, it is necessary to completely exclude from the diet foods that increase gas formation in the intestines:

• bread, buns, muffins;
• dairy and sour-milk products;
• carbonated drinks;
• foods rich in fiber.

In addition, alcohol is prohibited.

On the day of computed tomography of the abdominal cavity, you can not eat or drink at least 3-4 hours before the procedure, so it is recommended to prescribe it in the morning or in the first half of the day so that the patient does not have to go hungry all day.

Failure to comply with these rules can distort the results of the study – the images may show blackouts and spots that are not related to the presence of diseases.

The night before, a cleansing enema or laxative is recommended to cleanse the intestines. At this time, you should drink plenty of non-carbonated mineral water.

When planning an examination with contrast, it is first necessary to pass an analysis for creatinine.

If medications are taken, the doctor should be warned about this. In some cases, the doctor prescribes drugs that block x-rays – they, in some way, act as a contrast agent, if the contrast itself is not planned during the CT scan.

If you have with you to the procedure, you need to take:

• doctor’s referral;
• an extract from the medical record;
• the results of previously made examinations and analyzes (they may be prescribed by a doctor in preparation for a CT scan, or as part of a general diagnosis of the body).

What does a non-contrast abdominal CT scan show?

This type of tomography is used more often than CT with contrast, as it is more harmless, costs somewhat less and is easier to perform, without double scans and manipulations with the introduction of a contrast agent with special syringes or catheters.

CT without contrast makes it possible to assess the condition of the abdominal cavity and each organ separately, check for developmental anomalies, and identify the presence of stones in the kidneys, gallbladder, biliary tract and ureter, an increase or decrease in the size of organs, changes in their tissues.

This type of study helps to establish the presence and number of calcifications in the arteries or pancreas, to determine aneurysm, cirrhosis, the development of malignant tumors, the spread of metastases.

Why is contrast needed?

The contrast agent contains iodine. Distributed over the tissues of organs, it makes it possible to most clearly visualize the internal structures of these tissues. The drug is administered intravenously, and spreads through the vessels, staining them, after which it accumulates in the tissues, improving their display on the pictures. Since it is transported in the blood, its highest concentration is found in tissues and organs that are richly supplied with blood. For this reason, the method with contrast is used to identify pathological foci with increased blood flow. The method is effective for detecting and studying the texture of neoplasms in the organs of the abdominal cavity, it can even reveal those that are not able to detect CT without contrast. As a result of the introduction of contrast, the state of the vessels, the presence of pathological constrictions and functional pathologies in them will be displayed on the picture or monitor.

During the day, the substance is completely excreted from the body through the kidneys.

How is the procedure of computed tomography of the abdominal organs

CT can usually be performed both in a hospital setting and in a clinic.

If a CT scan of the abdomen with contrast is planned, a venous catheter is inserted into the patient’s cubital vein before the scan begins. This mechanism, with the help of an automatic injector, gradually delivers a contrast agent into the body. In this case, we are talking about CT with bolus contrast. It is also possible to use a syringe to inject contrast. To examine the upper gastrointestinal tract, contrast is administered orally, if you need to examine the pancreas, kidneys or liver in detail, the contrast is injected parenterally – into a vein.

The patient is placed on the tomograph table, asked to take the most comfortable position. It is especially important that the person does not move during the process, so sometimes it is necessary to fix it with straps. The doctor may ask you to hold your breath for a short time.

The duration of the tomography is no more than 30 minutes. All this time the patient will be under the supervision of medical personnel. The radiologist and the radiologist are in the next room, but they can see and hear the subject, and communicate with him. After the procedure, the patient may be given plenty of fluids to speed up the process of removing the contrast.

For those people who suffer from claustrophobia, it is recommended to undergo an examination on an open-type tomograph.

Examination of the results of CT scan of the abdominal organs

After the end of the examination, the patient is given pictures of the abdominal cavity, a digital media with saved tomography results, as well as the conclusion of a radiologist. It is necessary to take into account the fact that the quality of the images directly depends on the sensitivity of the tomograph, on the patient’s careful compliance with the preparation rules, on whether he was able to remain motionless in the process.

If all the requirements have been met, the doctor will be able to detect the location, size and number of foci of inflammation, stones, neoplasms, thrombosis, and other disorders, and the degree of their spread in the picture.

Advantages of computed tomography over other types of examinations

When prescribing a CT scan of the abdominal cavity, doctors focus on the fact that the procedure provides a high quality image of the organs, reveals even the smallest changes in the internal organs with the smallest details. In the process, the subject does not experience pain or discomfort. The tomography itself is carried out quickly, and gives a very small radiation load on the body. The procedure is considered more informative than, for example, ultrasound.

Computed tomography of the abdominal organs is a progressive method for examining internal organs and retroperitoneal space, which allows you to get layered images of tissue structures. It is distinguished by high accuracy, painlessness and informativeness of the results. As a result of CT, it is possible to detect primary and secondary volumetric formations, abscesses, lesions of the retroperitoneal nodes, injuries and aneurysms, and the spread of metastases. The value of the information obtained lies in the fact that it can be used to identify pathologies at the earliest stages, develop a treatment strategy, and monitor the effectiveness of its implementation.