Trans Ureteral Lithotripsy
Ureteroscopy is a common procedure whereby a stone can be removed via a special telescope, or in certain instances, a laser can be used to break the stone up into very small bits that can be passed. Ureteroscopy is done under anesthesia in the operating room. It takes between 30 minutes and 2 hours depending on the stone and your anatomy, and can be very simple or quite complex.
The procedure first requires the doctor to look inside your bladder and to put in a special guide wire to allow the ureter to be entered. X-rays may be done prior to the actual procedure to locate the stone, and the procedure is done with the aid of real-time x-ray (called fluoroscopy). Depending on the location of the stone, either a shorter semi-rigid scope, or a longer flexible ureteroscope is then inserted into the ureter until the stone is located.
Occasionally the ureter must be dilated with a special balloon to allow the scope to be inserted.
The ureteroscope is a special, very thin instrument used to look directly at and visualize the inside of the ureter. Some ureteroscopes are flexible like a small, very long straw. Others are more rigid and firm. Overall more than 400 ureteroscopic procedures are performed annually in our center.
Ureteroscopy is a routine procedure performed by urologists. The most common indication is to treat upper urinary tract calculi, particularly those that are either unsuitable for extracorporeal shockwave lithotripsy or are refractory to that form of treatment. Other common indications include evaluation of an abnormal lesion noted on findings from less invasive imaging tools (eg, intravenous pyelography [IVP], MRI, CT scan) or localizing the source of positive urine culture or cytology results. Thus, ureteroscopy is often an essential part of the diagnostic algorithm and can also be employed therapeutically to treat the underlying disorder.
Diagnostic indications for ureteropyeloscopy are as follows:
- Abnormal imaging findings - Filling defect
- Obstruction - Determination of etiology
- Unilateral essential hematuria
- Localizing source of positive urinary cytology results, culture results, or other test results
Therapeutic indications for ureteropyeloscopy are as follows:
- Endoscopic lithotripsy
- Retrograde endopyelotomy
- Incision of ureteral strictures
- Improvement of calyceal drainage
- Treatment of calyceal diverticular lesions
- Treatment of malignant urothelial tumors
- Treatment of benign tumors and bleeding lesions
- Useful preoperative imaging studies depending on the clinical presentation include the following:
- Renal sonography
- CT scan
When therapeutic ureteroscopy is performed, a safety guidewire is essential. This allows for multiple passes of the instrument while maintaining access to the upper urinary tract. An example would be treating a distal ureteral stone, for which a rigid ureteroscope is passed up the ureter beside the safety guidewire and laser energy is delivered through a small quartz fiber to fragment the stone. An accessory such as a wire prong grasper or basket then can be employed to extract fragments with multiple passes of the endoscope. The use of a ureteral sheath minimize trauma to the ureteral meatus and intramural ureter in such situations.
In many situations, a backstop may be useful to prevent proximal migration of distal ureteral stones. The Stone Cone and Parachute kidney-stone baskets are both useful for this purpose.
Once the stone is seen through the ureteroscope, a small basket-like device can be used to grab the smaller stones and remove them. If a stone is too big to remove, a laser fiber can be passed through the ureteroscope and the stone can be fragmented. If the doctor has to do much maneuvering to crush the stone, a stent may be placed to drain the kidney until the swelling due to the procedure resolves. Occasionally, the stent itself can cause some symptoms.
Larger stones may require fragmentation with lithotripsy through the scope. This may be accomplished with the jackhammer effect of a lithoclast or by using electrohydraulic, ultrasonic, or laser lithotripsy.
The risks of cystoscopic-ureteroscopic procedures include infection, bleeding, failure to remove the stone, ureteral injury.