Since the introduction of ureteroscopy in the 1980s, the treatment of ureteral stones has undergone a fundamental change.
The application of new small-diameter rigid, semi-rigid and flexible ureteroscopes, the extensive combination of new lithotripsy equipment such as ultrasound lithotripsy, fluid electrolysis, pneumatic ballistic lithotripsy and laser lithotripsy, and the application of ureteroscopic direct vision lithotripsy basket extraction have greatly improved the success rate of minimally invasive ureteral stone treatment.
The choice of ureteroscopic stone extraction or lithotripsy method should be based on the site, size, composition (density), co-infection, available instruments and equipment, the technical level and clinical experience of the urologist, as well as the patient’s own conditions and wishes.
Indications
(1) Ureteral stones in the lower part of the ureter.
(2) Middle ureteral stones.
(3) Upper ureteral stones after ESWL failure.
(4) “Stone street” after ESWL.
(5) Stones complicated by suspected ureteral epithelial tumor.
(6) Ureteral stones with X-ray.
(7) Embedded stones with long residence time and difficult ESWL.
Contraindications
(1) Uncontrollable systemic hemorrhagic disease.
(2) Severe cardiopulmonary insufficiency that cannot tolerate the procedure.
(3) Uncontrolled urinary tract infection.
(4) Severe urethral stricture that cannot be resolved by endoluminal surgery.
(5) Severe hip deformity with difficulty in osteotomy position.
Pre-operative preparation
(1) Preoperative preparation is approximately the same as that for open surgery. If bacteria are present in the urine culture, choose sensitive antibiotic treatment to make the urine sterile; even if the urine culture is negative, broad-spectrum antibiotics should be chosen to prevent infection on the day of surgery.
(2) Patients and their families must be informed that the surgery is mainly to relieve the obstruction and the damage of stones on kidney function, stone residual is unpredictable before surgery, residual stones can be combined with SWL and Chinese medicine for stone removal, meaningless residual stones can be reviewed regularly.
(3) Preoperative x-ray localization films are taken to confirm the stone location.
(4) The operating room is routinely equipped with x-ray fluoroscopy and B-ultrasound equipment.
Operation method
(1) There are three types of ureteroscopes currently in use: rigid, semi-rigid and flexible. Rigid and semi-rigid ureteroscopes are suitable for lithotripsy and stone extraction of middle and lower ureteral stones.
Soft ureteroscopes are mostly used for lithotripsy and stone extraction of middle and upper ureteral stones, especially upper segment or kidney stones (see 5.3.4).
(2) The patient is placed in a lithotomy position, the bladder is first examined using a ureteroscope, and then a safety wire is introduced under the guidance of a guide
The ureteroscope is introduced under the guidance of a safety wire. Whether the ureteral opening needs to be dilated depends on the thickness of the ureteroscope and the size of the ureteral lumen. Both rigid or semi-rigid ureteroscopes can be inserted retrograde into the upper ureter under fluoroscopic surveillance. A flexible ureteroscope requires insertion into the ureter under its guidance with the aid of a 10-13F ureteroscope sheath or a safety guidewire introduced through a connector (see 5.3.4.4). During the approach, the pressure and flow rate of the irrigating fluid are adjusted using a syringe or a fluid perfusion pump to maintain a clear view of the procedure.
(3) For stones in the middle or upper ureter or stones at the PUJ or larger stone fragments, the following methods can be used to prevent or reduce the stones from slipping back into the renal pelvis or calyces: ① the pressure of the irrigation fluid should be minimized; ② adjust the position such as head-high foot position; ③ reduce the energy and frequency of lithotripsy; ④ fix the stones with lithotripsy blue and then lithotripsy; ⑤ lithotripsy starts from the edge of the stone side and try to break the stones (5) Start from the edge of the stone and try to break the stone into pieces, leaving the ureteral side of the stone until the last stone is broken.
(4) After the stone is seen through the ureteroscope, the stone is crushed into pieces of less than 3 mm using lithotripsy equipment (laser, pneumatic ballistic, ultrasound, liquid electricity, etc.). For those small stones and fragments ≤5 mm in diameter, they can also be removed with a lithotripter or lithotripter.
Postoperative placement of double J tube
It is controversial whether to place a double J tube after ureteroscopic lithotripsy. It is recommended to place a double J tube in the following cases: (1) large embedded stones (>1cm); (2) significant edema or bleeding in the ureteral mucosa; (3) ureteral injury or perforation; (4) polyp formation; (5) ureteral stenosis with/without simultaneous ureteral stenosis endotomy; (6) large stones with significant fragment load after lithotripsy, requiring postoperative stone removal; (7) incomplete lithotripsy or lithotripsy failure, with postoperative stone removal; (8) lithotripsy failure. (7) incomplete lithotripsy or lithotripsy failure, requiring postoperative ESWL treatment; (8) with significant upper urinary tract infection. Generally, the double J tube is placed for 1-2 weeks, or 4-6 weeks if ureteral stenosis is performed at the same time.
Complications and their management
The incidence of complications is significantly related to the equipment used, the skill level of the operator and the condition of the patient. The current literature reports a complication rate of 5-9%, with more serious complications occurring at a rate of 0.6-1%.
6-1%.
(1) Recent complications and their management.
①Infection: apply sensitive antibiotics for active anti-infection treatment.
②Submucosal injury: Placement of double J stent tube for drainage for 1-2 weeks.
③Pseudotract: Placement of double J stent tube for drainage for 4-6 weeks.
④Perforation: one of the major acute complications. Small perforations can be placed with double J stent tubes for drainage for 2-4 weeks, and if the perforation is serious, surgical repair (ureteral end-to-end anastomosis, etc.) should be performed.
⑤ Ureteral mucosal avulsion: It is one of the most serious acute complications. It should be actively surgically reconstructed (autologous kidney transplantation, ureteral bladder anastomosis or ileal substitution ureterization, etc.).
(2) Long-term complications and their management
Ureteral stenosis is one of the major long-term complications, and its incidence is about 0.6-1%. Ureteral mucosal injury, pseudo-channel formation or perforation, ureteral stone impaction with polyp formation, and ureteral mucosal destruction due to multiple ESWL are the main risk factors for ureteral stenosis. Long-term complications and their management are as follows.
①Ureteral stenosis: endotomy of ureteral stenosis or end-to-end anastomosis of stenotic segment excision.
(ii) Ureteral occlusion: stenosis segment resection end-to-end anastomosis or ureteral bladder reimplantation.
③Ureteral reflux: mild: follow up. Severe: ureteral bladder reimplantation.