Computed tomography

Computed tomography (CT)) - an imaging method for obtaining an image using digital reconstruction, which is based on X-ray radiation. The study is carried out using an apparatus - a computer tomograph consisting of a detector and an X-ray tube. The X-ray tube creates radiation that passes through the patient's body, which is perceived by detectors and converted by a computer.The result is two-or three-dimensional images.

A person is placed on a special table, inside a CT scanner, to improve the image quality, rest and immobility are necessary during the scan. The doctor or laboratory assistant gives instructions for holding your breath, if necessary.

Indications for computed tomography.

To date, computed tomography is considered the main X-ray method of research, and is necessary for the diagnosis of various diseases of the organs, such as:

• developmental abnormalities;
• oncological diseases (neoplasms of the head, neck, abdominal cavity and pelvis, chest organs,);
• vascular diseases (stroke, atherosclerosis, various malformations, aneurysms);
• foreign bodies, cysts (including parasitic ones);
• inflammatory processes of various localization (cholecystitis, pancreatitis, pyelonephritis);
• diseases caused by a specific pathogen (tuberculosis);
• enlarged lymph nodes (including oncological diseases, such as lymphomas);
• liquid accumulations, purulent foci, blood;

With this method, doctors plan the volume of surgical intervention, determine the result of treatment, and check the correct location of shunts or stents.

Contraindications to computed tomography.

Relative contraindications:

 Without contrast:

• Pregnancy;
• The patient's weight is the highest maximum for the tomograph.

With contrast:

• The presence of allergic reactions to the contrast agent;
• Kidney failure (need to consult a nephrologist);
• Severe diabetes mellitus (it is necessary to consult an endocrinologist);
• The body weight is more than the maximum for the device;
• Pregnancy (teratogenic exposure to X-rays);
• Diseases of the thyroid gland (it is necessary to consult with an endocrinologist);
• Myeloma disease.

There are no absolute contraindications, the method can be used in patients in any condition. When examining pregnant women and children, you should weigh the risks and benefits (need) of CT in each specific case.

The possibility of introducing iodine-containing contrast agents is discussed separately. Due to the risk of allergic reactions, each administration should be justified.

Preparation for the study.

The patient's preparation for computed tomography will vary depending on the type of study being performed, the purpose of the study, and the need for the administration of a contrast agent:

• standard study ("Native", without the introduction of a contrast agent). It is used to detect pathologicities of the skull, thoracic cavity, spine, brain, etc. This study does not require special training.
• examination of the abdominal cavity (without contrast agents). When examining the gastrointestinal tract, 2-3 days before the study, it is recommended to exclude from food products that contribute to increased gas formation. The study is carried out on an empty stomach, 30 minutes before the study, you need to pour 0.5-1 liter of water.
• in a CT study with intravenous administration of a contrast agent, it is necessary to prepare the patient, including the collection of anamnesis, including the identification of allergic reactions of the patient, assessment of the function of the kidneys and urinary tract, thyroid gland, using laboratory methods of blood testing.
• Duration of the computed tomography study.

As a rule, the study takes 15-30 minutes (depending on the specific diagnostic tasks). 

Recovery period after the procedure.

Computed tomography involves the use of X-rays, all doses are biologically determined and can not harm the patient's health. After a CT scan without intravenous contrast, there is no need for recovery. After a CT scan with the introduction of a contrast agent, it is recommended to increase the fluid intake. With proper nutrition and a competent increase in the water balance, 90% of the contrast agent is excreted by the body in the first day.

Note: : Do not overdo it with an increase in water load, if there are diseases of the kidneys and urinary tract.