A ureteroscopy is a medical procedure performed to remove kidney stones which haven’t been able to pass through the ureter, which is the connection between the kidney and the bladder.
Ureteroscopy involves the passage of a small fiberoptic instrument called a ureteroscope through the urethra and the bladder into the ureter. This 3 mm diameter optical instrument is connected to a light source, sterile water irrigation and a camera. It also contains a working channel through which various instruments are introduced, such as metal guides, laser fibres and basket probes. With this device, our urologists can look into the ureter, find the stone and remove it.
The surgeons can see where the instruments are going inside your body with the help of X-ray technology.
Why do a flexible ureteroscopy for a kidney stone?
A ureteroscopy can be a second attempt to intervene if this first alternative fails. It can also serve in a cancer diagnosis or the treatment of ureteral abnormalities such as stenosis (narrowing of channels or vessels).
The purpose of the procedure is to break the stone into little pieces with a laser fibre. The fragments are left in place or can be removed by a tiny basket probe.
The treatment is usually very effective.
How is a flexible ureteroscopy performed for a high renal stone?
The procedure is performed under spinal anesthesia at the Centre Métropolitain de Chirurgie. The patient is placed in a lithotomy or gynecological position.
It requires using a radiology device to perform fluoroscopy to orient and assess the fragmentation by laser fibre (C-ARM). A radiology technician handles this part of the procedure.
A rigid cystoscope is introduced into the ureter under direct vision using the camera down to the level of the bladder. The ureteral opening is identified and cannulated by a catheter to introduce a first safety metal guide to the renal cavities and pelvis level. A second work guide is introduced using a double-lumen catheter.
A ureteral access sheath is usually introduced until the stone is removed. The ureteroscope is then easily inserted inside this catheter, and then a laser fibre is inserted into the working channel of the ureteroscope. The kidney stone is fragmented progressively under direct vision using the camera. Controlled pressure water irrigation is necessary to ensure proper visibility. If bleeding compromises vision, the surgery is stopped. If this happens, a second session may be scheduled, or other alternatives may be offered because there’s no guarantee that the stone was sufficiently broken up.
After a ureteroscopy procedure, it's common to leave a double-J stent in place to prevent lower back pain caused by obstruction due to swelling, which is unrelated to kidney stone formation.
What are the risks and possible complications of a flexible ureteroscopy?
The most common difficulty (10 percent) is that the stones fail to move because of a narrow ureter. This is why the need for several operating times is always considered in cases where the ureter is not prepared beforehand by a double-J catheter or if the stone is bulky. To avoid the risk of trauma, a double-J is temporarily installed so that the ureter expands. It’s then necessary to postpone the procedure and to re-intervene a few weeks later.
The discomforts of a double-J probe are common. Infection or sepsis is possible despite sterile urine and preoperative antibiotic prophylaxis. They can occur quickly on the same day or later.