CT urogram is a layer-by-layer scanning of the kidneys and urinary tract with X-rays with computer processing of the obtained tomographic sections. CT urogram can be performed natively (without contrast) and with intravenous administration of a contrast agent. The scanning area includes the kidneys, renal arteries and veins, ureters, and bladder. According to the cross-sections obtained during the scan, it is possible to get a clear idea of the morphological features of the urinary tract (location, size, structure of organs) and tissue density. By means of CT urogram, anomalies of structure, concretions, neoplasms and metastases, cysts and abscesses of the kidney, ureterohydronephrosis and other pathology can be diagnosed.
Indications
- detection of radiopaque concretions in the projection of the kidneys, ureters and bladder.
- a study with an assessment of the structure of concretions of the urinary system
- renal colic, a history of urolithiasis
- inflammatory damage to the kidneys and paranephral tissue
- suspected adrenal tumor
- identification of concomitant changes in the pelvic organs and in the upper urinary tract, complications on their part, as well as the exclusion of various developmental anomalies
- injuries of the urinary system organs
Preparation
Before the appointment of a tomography, the patient informs the doctor about all possible allergic reactions that may be caused by the introduction of an iodine-containing contrast agent. The night before – a light dinner, no breakfast on the day of the study. The night before, a cleansing enema, or intestinal cleansing with a Fortrance solution. Examination of the abdominal cavity is performed on an empty stomach. If a CT scan is scheduled in the afternoon, you can easily have breakfast in the morning, not lunch. If the patient underwent an X-ray examination of the digestive tract (esophagus, stomach, irrigoscopy) with barium suspension, computed tomography can be performed no earlier than 7 days. To get informative results CT in the diagnosis of pelvic organs is a prerequisite – a filled bladder. Do not urinate for 1 hour, and also drink 1 liter of water an hour before the tomography. It is necessary to come to the study with an “empty bowel”. 3 hours before the examination, it is necessary to empty the intestines with a cleansing enema or a drug Microlax
General requirements for CT with contrast:
To perform the study, you must have the result of a creatinine blood test with you, the limitation period is no more than the 30th day from the date of delivery of the biomaterial. Be sure to inform the radiologist before the examination with contrast:
- do you have an allergy to iodine, medicines and food
- do you suffer from diabetes, asthma, heart or thyroid disease
Methodology of conduction
The study is carried out lying on your back (if necessary, it can be supplemented with a position on your stomach or on your side), clothing should be without metal objects. A body scan is being performed. CT urogram without contrast agent lasts up to 1 minute. If necessary, the doctor may ask the patient to hold his breath for a few seconds.
The dose load is about 12 mSv (depends on the patient’s body weight)
Volumetric constructions (reconstructions):
After the end of the study, volumetric reconstructions of the urinary system and bone structures are carried out at the level of the study (images in 3D or 4D, MPR (multi-plane reconstructions)) with color selection of concretions.
Advantages
- CT examination by the Dual Energy method (using two X-ray tubes) allows you to assess the chemical composition of urinary tract concretions, which affects the further tactics of attending physicians.
- speed of research execution
- three-dimensional and four-dimensional modeling of the organs of the urinary system allows for a more visual assessment of the organs of the urinary system
- the ability to diagnose radiopaque concretions, their density
- CT examinations of patients with metal implants (joints, internal and external fixation devices, etc.), including with the presence of an electrocardiostimulator, are performed in full
Disadvantages of the study for the diagnosis of a specific pathology and localization of pathological changes
- the study is not carried out for pregnant women
Additional research if necessary:
- Ultrasound of the retroperitoneal space, abdomen and bladder.
- Urethrography, retrograde cystography.
- For clinical indications, supplement with radiography of the pelvic bones (excluding fracture) or CT of the pelvic bones.
