Intravenous urography is a method of studying the urinary system, in which the contrasting substance evaluates the excretory capacity of the kidneys and the state of all organs responsible for urination.
Such a detailed analysis of the urinary tract and kidney becomes possible due to the contrast agent that is administered to the patient. The contrast passes through the urinary tract and is displayed on X-rays. This makes it possible to pinpoint the cause of many diseases, especially those associated with impaired urine outflow from the kidneys.
The essence of the study
The study is based on the filtration capacity of the kidneys. With intravenous urography of the kidneys with the introduction of contrast, it becomes possible to determine the condition of the cup-pelvis structures, which are not visible on an ordinary roentgenogram.
Contrast substance is selected in each case individually. In this study, it is important to contrast:
- did not have the opportunity to accumulate in tissues;
- characterized by good X-ray contrast;
- had a low nephrotoxicity;
- not metabolized;
- did not participate in metabolic processes of the body.
To conduct an x-ray study begin after 5-6 minutes, when the contrast only enters the kidneys. Further pictures are taken at the 15th and 21st minutes. If the contrast is completely displayed during this time, no more pictures are taken. And if the contrast is still present, then take a picture also in 40 minutes.
In this survey, it is the rate of intravenous contrast withdrawal that is important, and the degree of impairment of the excretory function of the kidneys is determined from it.
Indications for analysis
All indications for the use of intravenous excretory urography are divided into absolute and recommended.
Such an analysis is mandatory in the following cases:
- presence of urinary tract anomalies;
- chronic kidney disease;
- presence of kidney tumors;
- stones;
- omission of the kidneys;
- detection of changes in the bladder.
It is also possible to conduct studies with a decrease in the excretory function of the kidneys or anomalies of the ureters.
There are also contraindications to intravenous urography:
- The procedure is strictly prohibited for patients with hyperthyroidism .
- Also, do not perform urography in patients who have an allergic reaction to iodine.
- Analysis can not be done during a period of fever.
It is not an absolute prohibition, but, nevertheless, experts do not recommend doing research for women during the menstrual cycle and during pregnancy.
Preparing for the procedure
Preliminary preparation of the patient for the procedure of intravenous urography begins with the study of the anamnesis of the disease. It is also recommended to clean the bowels before the test. This will facilitate a more detailed visualization of the kidneys on X-rays.
During preparation for intravenous urography of the kidneys, the patient should adhere to the dietary regime several days before the study. It consists in the following:
- Eliminate products that cause gassing (black bread, milk, legumes and other products).
- Before starting the study itself, do not drink a lot of water.
- After three hours after the evening meal, do a cleansing enema .
- For breakfast, before the test, you should drink tea with cheese.
All the advice of doctors on how to prepare for intravenous urography is that you need to clear the bowels of excess gases and stool. Therefore, it is recommended to adhere to the diet and perform cleansing with enemas.
Correctly performed procedure helps to diagnose the causes of many diseases associated with the excretory function of the kidneys.