What is the kidney mirroring?Schematic representation of the anatomy and structure of the kidney in kidney stones. Click to enlarge.
A kidney mirror can be done in two ways: either transurethral, that is, through the urethra, or percutaneously, through the skin. In a transurethral reflection (ureterorenoscopy, URS), the ureter and the kidneys are mirrored, with the percutaneous intervention (percutaneous nephrolitholapaxy, PCNL / PNL) concentrating only on the internal cavity of the kidney (the renal pelvis). The latter method is very effective but is much more invasive than the former. Both procedures are done under anesthesia.
Direct kidney mirroring or nephroscopy is a so-called percutaneous procedure, that is, it is through the skin. Because the skin cover is cut open, kidney mirroring is seldom done to make a diagnosis. First of all, the procedure is used to remove kidney stones.
In a ureter and kidney mirror, the instrument is guided through the bladder into the ureter. Ideally, the attending physician can advance the device to the kidney to remove the kidney stones there. In both procedures, the physician works with the continuous control of an ultrasound device or a camera.
Function, effect & goals
Kidney reflection is a therapeutic method. The most important function of percutaneous kidney transplantation is the removal of kidney stones, which can be found in the inner cavity of the kidney and because of their size can not pass through the ureter.
Even the large kidney stones, which can not be smashed, are removed by the percutaneous kidney mirror. Stones with a diameter of 3 cm are removed in this way. Kidney congestion can also help with kidney transfusion by removing urine from the renal pelvis. A kidney congestion occurs when the urine can not flow in the direction of the bladder due to congestion in the ureter.
In a percutaneous kidney mirror, the patient has to lie on his stomach, so that the doctor can make a cut through the skin of the lateral abdominal region. This incision allows the penetration of an endoscope that is advanced to the kidney. Thus, the internal cavity of the kidney, the renal pelvis, is punctured.
The whole process is controlled with an ultrasound machine because it is a very precise procedure and otherwise the doctor would not be able to see exactly where the endoscope is. After the instrument has been inserted, the stone is smashed by a medical "jackhammer", laser or ultrasound, and the fragments are removed directly.
In a ureterorenoscopy, the stones are removed "naturally". The instrument is guided through the bladder into the ureter, eventually to the kidney. The stones are either pulled out or, if they are too large, previously crushed with laser beams or ultrasound. Also in this method, the steps are tracked directly. Thanks to modern technology, very small cameras can be placed at the top of the device.
The ureter is usually prepared for engagement by inserting a splint. This splint serves to relax the ureter, making the procedure less risky.
Risks, side effects & dangers
Like all medical procedures, kidney mirroring carries dangers and complications. These include intraoperative or postoperative bleeding or injuries to the ureter and renal pelvis.
In addition, fever may occur as a result of the procedure. Very rarely it can lead to kidney loss. It can happen that the rinsing fluid, which is needed for the mirroring, comes into the bloodstream. This dilutes the blood.
Neither a transurethral nor a percutaneous surgery may take place in an untreated urinary tract infection. For coagulation disorders, the two methods are recommended only in urgent cases. Percutaneous kidney transplantation is prohibited during pregnancy. This method is also contraindicated for a tumor in the access area.
The likelihood of the above complications depends on the size and location of the stones or previous operations.