Pyelography

One of the X-ray methods for diagnosing diseases of the urinary system is pyelography (pyeloureterography, ureteropyelography), in which the study of the kidneys and ureters is carried out using special contrast agents. [1]

Indications for the procedure

When  examining the kidneys, the  need for pyelography is determined by the doctor, especially when patients complain of intense  pain in the kidney area , problems with urination, and also in the presence of  hematuria  (blood in the urine). And when other imaging methods do not allow to find out the state of such structures as the renal pelvis (Pelvis renalis), cups (Calices renales) and ureters (Ureter), they resort to pyelography - an  X-ray of the kidneys  with the introduction of a contrast agent. [2]

Dysfunction of the listed structures of the urine storage and excretion system is possible in various pathologies and  diseases of the kidneys , and the diagnostic task is to find their possible causes. In addition, pyelography can be used to detect abnormalities in the development of the kidneys (hyper- and hypoplasia, medullary spongiform kidney, renal cups diverticulum, etc.) and to check the location of the catheter or ureteral stent. [3]

For better visualization (image enhancement), water-soluble non-ionic contrast agents containing iodine are used for pyelography, for example, Iopamidol,  Pamiri , Optiray,  Ultravist 300  , etc. [4]

Preparation

Preparation for this examination of the kidneys includes stopping the intake (in a few days) of analgesics, neuroleptics, antidepressants, beta-blockers; in the evening on the eve of the procedure - stopping food intake after 18-19 hours and cleansing the intestines with a laxative.

On the day of the study, in the morning they also do not eat (and do not drink liquids) and re-cleanse the intestines by doing an enema.

In the hospital, you should change into loose indoor clothing, jewelry and any metal objects that might interfere with the X-ray image.

Technique of the pyelography

With pyelography, the technique depends only on how the radiopaque contrast agent is injected.

Retrograde pyelography or ascending pyelography involves the introduction of a contrast agent into the orifice of the corresponding ureter through the urethra using a cystoscope, through which a catheter is inserted, and through it a contrast agent. The procedure requires an epidural. [5]

Antegrade pyelography, which is more often used when obstruction of the upper urinary tract is suspected, is performed with the introduction of a contrast agent through a skin puncture (puncture with a needle) into the lateral region of the back - directly into the renal pelvis. In this case, the accuracy of the puncture and the movement of the injected drug from the kidney into the ureter and bladder is monitored by fluoroscopy. The procedure is anesthetized with a local anesthetic. [6]

Also, minimally invasive intravenous pyelography or excretory pyelography is performed, in which a contrast agent is injected into a vein of the arm at regular intervals. Monitoring and control of the procedure is carried out using continuous fluoroscopy converting X-rays into video images. [7]

A series of X-ray images (pictures are also taken at intervals) and video, which is produced by an X-ray machine and a detector (located above the patient lying motionless on the table), allow us to assess the conductivity of the ureters and urinary tract, which can be disturbed due to the presence of renal calculi, tumor formations, congenital anomalies, in men - due to hyperplasia or tumor of the prostate gland. [8]

Contraindications to the procedure

Pyelography is contraindicated in pregnancy, elevated body temperature, exacerbation of any existing diseases, allergy to iodine, hyperthyroidism and thyrotoxicosis, acute or  chronic renal failure  (including chronic diabetic nephropathy), and malignant blood diseases.

Diabetes mellitus, severe arterial hypertension, decreased circulating blood volume (hypovolemia), as well as advanced age (over 70 years) are considered relative contraindications.

Complications after the procedure

Due to the use of radiocontrast substances containing iodine, negative consequences of pyelography are possible in the form of deterioration of renal function (with a decrease in the glomerular filtration rate and an increase in serum creatinine), seizures, tachycardia, shortness of breath, and the development of anaphylactic shock.

Possible complications of retrograde pyelography: nausea and / or vomiting, pain when urinating, bleeding, urinary tract infections, sepsis. And with antegrade pyelography, there is also a risk of urinary cyst formation.

Care after the procedure

The type of pyelography performed determines what kind of care is required for patients and how long their rehabilitation will take after the procedure. On an outpatient basis or in the ward of a medical institution where the patient is inpatient treatment, the medical staff must monitor his condition: monitor the heart rate, respiration, and blood pressure. Also, during the day, diuresis and the presence of blood in the urine are monitored (a small amount of it immediately after antegrade or ascending pyelography is considered normal).

For painful urination, the doctor prescribes pain relievers that do not reduce blood clotting.

If fever begins at home after pyelography; the puncture site is redder, gets wet or hurts; the amount of blood in the urine increases or urination is difficult, you should immediately consult your doctor.

Reviews

The reviews of specialists in the medical literature on this method of visualizing the structures of the urinary system indicate that today, in many cases, ultrasound is used -  ultrasound of the kidneys and ureters  (including with color Doppler mapping), computed  [9]or magnetic resonance imaging.