What is cystography?In urinary tract disorders, it may be necessary to examine the urinary bladder and urinary tract. Cystography allows you to look at these internal organs.
Cystography is an x-ray of the bladder, which uses a contrast agent for better visibility.
Among other things, it is necessary to detect malformations or foreign bodies in the area of the urinary bladder and the urinary tract if malfunctions of the urinary tract occur. As contrast agents are usually iodine-containing agents used. Synonym the term cystogram is used.
Function, effect & goals
Depending on the indication and the objective, different forms are used for the examination. All examinations are performed by filling the empty bladder with a contrast agent. Multiple x-rays capture the path of the contrast agent through the urinary tract.
The different methods differ primarily by the way in which the contrast agent is introduced. In retrograde cystography, the contrast agent is brought into the bladder using a catheter and then sealed. X-rays are taken standing and lying down. This form of examination allows a study of the renal pelvis and the ureters. It is used when there is a suspicion of stones in kidney or ureter or ureteral anomalies.
Likewise, tumors in the renal pelvis or ureter become visible to the physician through this examination method. Also, bladder injuries can be detected or eliminated using this method of examination. Because the contrast agent is not absorbed via the bladder, this procedure is preferable to intravenous fluid testing for contrast agent allergies. Similarly, the conduct of intravenous cystography, which is also referred to as intravenous urography or excretory urography. The main difference here is the administration of the contrast agent.
This is not introduced via a catheter into the bladder but passes through the bloodstream into the excretory organs. This has the advantage that the kidney activity in the X-ray image can be displayed. In addition, the bubble exit is not closed in this method, so that the further path of the contrast agent can be followed. For infants and toddlers there is the possibility of expression urography. This is done similar to retrograde cystography but under general anesthesia. After the evaluation of the urinary bladder by the cystography, the contrast agent is then usually moved into the ureter by manual stimulation, whereby this can also be assessed.
The advantage of this examination method is that it creates less stress for the child than retrograde cystography. In polycystography different degrees of bladder filling are simulated using different amounts of contrast agent. This provides information about the distensibility of the bladder. An ultrasound examination is also possible. In contrast to ultrasound contrast medium cystography, the contrast agent is introduced by means of a catheter similar to retrograde cystography, but the imaging is not done by X-rays but by means of an ultrasound device.
Risks, side effects & dangers
The risks arise from the different examination methods. The main risk is an incompatibility of the contrast agent. however, if it is known in advance, it can be minimized by avoiding intravenous administration. In the case of acute cystitis, however, it is also possible to take up the contrast agent via the inflamed tissue. An acute urinary tract infection should therefore be ruled out in advance.
This also minimizes the risk of false positives. Furthermore, the catheter may cause irritation or injury to the urinary tract. Injuries in treatment by experienced doctors are very rare. More likely is a reaction to the materials used. If incompatibilities are known here, for example with respect to latex, these should be reported in advance to the attending physician.
The risk of urinary tract carryover and subsequent urinary tract infection is low due to the use of sterile materials and disinfection of the surrounding skin areas, but persists. As a rule, this can be combated well by the administration of antibiotics. In immunocompromised individuals, sometimes an antibiotic is also used preventively. Examination under general anesthesia has the usual risks of anesthesia. Again, if incompatibilities are already known or complications have occurred in previously performed anesthetic treatments, this should be reported to the doctor beforehand.
He will react accordingly and may use other medicines. Limited renal function should also be excluded prior to conducting the study. If the kidneys are not working properly, there is the possibility, especially with intravenous administration of contrast medium, that the contrast agent will not be eliminated or not completely eliminated. Another risk is the radiation exposure by X-ray. However, this is relatively low. Nevertheless, pregnancy should be ruled out before any examination.
For the documentation of the radiation dose so-called X-ray passes have been available for some years, in which the physician enters the examined body part as well as the radiation dose. If the known risks are outweighed, other methods of investigation are available. One possibility is ultrasound examination, ultrasound. However, this also carries risks in addition to the advantages of better imaging and lack of radiation exposure. Thus, certain examinations by sonography are not possible. In addition, in this type of examination, the contrast medium must always be introduced by means of a catheter, which can lead to the complications already described, such as injuries or inflammations.