CT of kidneys with or without contrast: preparation rules and procedure procedure
Computed tomography( CT) of kidneys is a diagnostic procedure that combines x-ray layer-by-layer examination of tissues and processing of acquired images with the help of specialized computer programs.
The result of the examination is a layered image of the kidneys, adrenal glands, other organs and structures that make up the urinary system, retroperitoneal space.Table of contents: Advantages of CT and the essence of the method Indications for the appointment of CT of the kidneys Contraindications to the procedure Preparation for examination How is the examination Interpretation of results Possible complications
Advantages of CT and the essence of the method
During the examination through the patient's body X-Different planes. The receiving device of the tomograph catches the rays reflected from the tissues.Information is processed using a computer program.At the exit, the doctor receives a three-dimensional image of the organ or system being examined.
There are 2 research methods - simple and using contrast agents.Usually iodine
Advantages of the CT study :
- accuracy and reliability;
- painless and non-invasive;
- does not require specialized training, except for CT with contrast agents;
- can be repeated several times during the year;
- high survey speed.
The procedure can be termed irradiation with X-rays. But in therapeutic dosages it will not cause significant harm to the body.
Modern devices - MSCT and SKT - use a spiral method of supplying X-rays during the survey.This increases the speed of the procedure and reduces the radiation load on the body.
Indications for the appointment of CT of the kidneys
Computed tomography allows you to obtain reliable information about the state of the urinary system, monitor the treatment process in dynamics.
The study is shown in the following cases:
- suspected or diagnosed kidney injury;
- hemorrhages in the cavity of the peritoneum, retroperitoneal space;
- pathology of the kidneys of inflammatory genesis, nearby organs;
- tuberculosis, abscess;
- pathology of the development of the urinary system, examination of vessels using contrast agents;
- carcinomas and adenomas of the kidneys and nearby organs, the search for secondary tumors with oncological pathology of the peritoneum, pelvis, lungs;
- cysts, hydronephrosis of the kidneys;
- alteration of lymphatic reservoirs in peritoneum and retroperitoneal space;
- presence of concrements;
- after installation of drainage, control during biopsy;
- control of treatment, including operative.
CT, as a method of monitoring treatment, is used extremely rarely, since research is expensive.And with positive dynamics in the patient of new information for the doctor, tomography will not give.
CT is non-invasive manipulation, so there is little contraindication to the study.If tomography with contrast agents is indicated, the number of contraindications increases.
When CT is not performed:
- Pregnancy.Radiation load during the procedure is negligible, but without acute CT indications, especially planned, it is better not to conduct. The estimated benefit from research for a woman should be greater than the estimated harm for the child. In this case, an alternative to CT scan will be MRI without contrast.
- Lactation - the first day after a CT scan, do not breast-feed your baby.Milk in this case is expressed.Then you can go back to feeding.
- Diabetes mellitus in severe forms.In a compensated state, the decision to conduct the study should be taken by the attending physician in conjunction with the endocrinologist.
- Myeloma is a malignant tumor of the lymphatic system.
- Excess weight of the subject.
The standard lifting capacity of the tomograph table with excess weight of the patient is 200 kg.The tunnel also has certain dimensions.Closed tomograph in these cases is not used, since it is problematic to place the patient in the device.
Indications for examination in open models are:
- Claustrophobia and panic disorders, epilepsy.
- Severe mental illness.
- A pronounced pain syndrome.
- High body temperature, signs of an infectious or respiratory disease.
- Pathologies in which a patient can not remain stationary for a long time.
The list of contraindications for CT with contrast agents has been extended.In addition to the main list, it includes the following items:
- allergic reactions to iodine or gadolinium;
- kidney failure.In this condition, the contrast agent will not be excreted by the kidneys in full;
- thyroid disease, in which iodine should not enter the body from the outside.
If the patient has contraindications to the procedure, then he must inform the attending physician or the radiologist conducting the examination.Also, it should be advised of previous CT, MRI or ultrasound examinations.
Preparation for examination
If CT is shown without contrast, special preparation for the procedure does not require .For several days it is recommended not to eat foods that cause fermentation in the intestines.It is also not advisable to take alcoholic beverages.
The test should be performed on an empty stomach.The last meal is not earlier than 5 hours before the tomography.
If CT scan with contrast is indicated, you should find out which preparation will be used. Some contrast agents are administered intravenously during the study, others - orally.In this case, the first dose of the drug is taken 12 hours before the tomography, the second - just before the study.CT with contrast is also performed on an empty stomach.It is forbidden to take liquids on the day of the procedure.
In the office of the scanner, you should remove all metal jewelry - chains, earrings, piercings.Warn doctor about the presence of implants in the body, devices to maintain the rhythm of the heart, metal joint prostheses.
You need to come to the procedure in a free, not embarrassing movement of clothes.In some clinics, the patient is given a one-time kit before the test.In this case, change your clothes.
How is the
screened? The patient is placed on the tomograph table.The examination is carried out in the supine position. To ensure immobility, use soft straps.Radiologist is in the next room with an observation window.
The table automatically enters the machine.The scanning part of the scanner starts moving and conducts a series of images in various projections.The duration of the procedure is from 10 to 20 minutes.This depends on whether a contrast agent is administered or CT is performed without the use of iodine or gadolinium.
If a contrast is indicated, the patient must first sign an agreement to use .Initially, a series of images are taken without using contrast, then the nurse introduces a contrast agent into the vein.After a certain time, a series of pictures is taken again.This allows you to evaluate the data before and after the introduction of contrast medium.
The presence of metallic taste in the mouth is not a sign of an allergic reaction.But if there are itching, nausea, dizziness, tachycardia or bradycardia, then it develops an intolerance of contrast medium.Immediately tell the radiologist!
Interpretation of results
Within an hour after the examination, the patient receives a written radiologist conclusion and a series of layered photographs. Interpretation of results is carried out by the attending physician, independent conclusions are undesirable and inexpedient.
In difficult cases, the attending physician may be present during the procedure in the tomography room to clarify the details of the examination.
The study is non-invasive and painless.Therefore, the probability of developing unpleasant symptoms after CT of the kidneys is extremely low.
What you can expect:
- feeling of discomfort from a prolonged immovable state;
- is an allergy to contrast agents;
- tenderness at the injection site;
- fear of loneliness, the development of other phobias.
CT of kidneys is an informative study.But it should be done only according to the doctor's prescription and only in those cases when other methods did not give a reliable answer to the doctor's questions.The purpose of such a procedure is inappropriate!
Chumachenko Olga, doctor, medical reviewer