Nitinol stone retrieval-assisted ureteroscopic management of lower pole renal calculi

Objectives. Current ureteroscopic intracorporeal lithotripsy devices and stone retrieval technology allow for the treatment of calculi located throughout the intrarenal collecting system. Difficulty accessing lower pole calculi, especially when the holmium laser fiber is used, is often encountered. We retrospectively reviewed our experience with cases in which lower pole renal calculi were ureteroscopically managed by holmium laser fragmentation, either in situ or by first displacing the stone into a less dependent position with the aid of a nitinol stone retrieval device.Methods. Thirty-four patients (36 renal units) underwent ureteroscopic treatment of lower pole renal calculi between April 1998 and November 1999. Lower pole stones less than 20 mm were primarily treated by ureteroscopic means in patients who were obese, in patients who had a bleeding diathesis, in patients with stones resistant to shock wave lithotripsy, and in patients with complicated intrarenal anatomy, or as a salvage procedure after failed shock wave lithotripsy. Lower pole calculi were fragmented with a 200-μm holmium laser fiber by way of a 7.5F flexible ureteroscope. For those patients in whom the laser fiber reduced the ureteroscopic deflection, precluding re-entry into the lower pole calix, a 3.2F nitinol basket or a 2.6F nitinol grasper was used to displace the lower pole calculus into a more favorable position, allowing easier fragmentation.Results. In 26 renal units, routine in situ holmium laser fragmentation was successfully performed. In the remaining 10 renal units, a nitinol device was passed into the lower pole, through the ureteroscope, for stone displacement. Only a minimal loss of deflection was seen. Irrigation was significantly reduced by the 3.2F nitinol basket, but improved with the use of the 2.6F nitinol grasper. This factor did not impede stone retrieval in any of the patients. At 3 months, 85% of patients were stone free by intravenous urography or computed tomography.Conclusions. Ureteroscopic management of lower pole calculi is a reasonable alternative to shock wave lithotripsy or percutaneous nephrolithotomy in patients with low-volume stone disease. If the stone cannot be fragmented in situ, nitinol basket or grasper retrieval, through a fully deflected ureteroscope, allows one to reposition the stone into a less dependent position, thus facilitating stone fragmentation.     

Post ureteroscopic stone surgery ureteral strictures management: a retrospective study

International Urology and Nephrology - To share experience in managing ureteral strictures following ureteroscopic lithotripsy. Ninety five patients diagnosed as ureteral strictures after...     

腔镜下处理输尿管结石并息肉

目的　介绍输尿管镜下处理输尿管结石并息肉的经验。　方法　１９９１ 年７ 月至１９９８年１１ 月,对１ ８４７ 例输尿管结石行２ ０５９ 例次输尿管镜检查及治疗,其中１０７ 例检查前曾先后行１ ～５次体外冲击波碎石（ＥＳＷＬ） 未获成功。　结果　１ ８４７ 例输尿管结石中并发息肉５５３ 例（２９ ．９ ％ ） ,其中４５０ 例在输尿管镜下处理成功（８１ ．４ ％ ） 。　结论　输尿管结石并息肉为常见病;输尿管结石嵌顿时间超过３ 个月,肾积水程度与结石大小不相符的患者不宜行ＥＳＷＬ;输尿管镜下行输尿管息肉切除及气压弹道碎石治疗效果满意。     

Ureteral injury from ureteroscopic stone manipulation

A ureteroscopy for stone removal resulted in a tear of the ureter and extensive necrosis requiring ureteroneocystostomy. Urologists are urged to report complications of upper tract endoscopy and to apprise patients of the inherent dangers.     

Perioperative antibiotic prophylaxis in ureteroscopic stone removal

OBJECTIVE: This study shall settle the question whether a perioperative single shot prophylaxis in connection with a ureteroscopic stone removal has an influence on the rate of postoperative urinary tract infections (UTIs) and inflammable complications or not. METHODS: 113 patients were included in this prospective randomized study. In 57 patients 250mg Levofloxacin p. o. was given approximately 60 prior ureteroscopy, 56 patients had no prophylaxis. The evaluation of all data which were processed electronically was carried out with the help of a standardised questionnaire. RESULTS: Postoperatively symptomatic urinary tract infections or inflammable complications of the urogenital tract were found in neither of the two groups. In the group without prophylaxis, the rate of the postoperative significant bacteriurias was significantly higher than in the group with prophylaxis (7 patients [12.5%] vs. 1 patient [1.8%]) (p=0.026). In six cases there was an E. coli bacteriuria; additionally a Kl. pneumoniae and a not specified Staphylococcus bacteriuria were detected in further cases. CONCLUSION: Single shot prophylaxis using 250 mg Levofloxacin p. o. can be considered as cheap, the patient not burdened and regarding the missed selection pressure to nosocomial pathogens the preferred manner of perioperative antibiotic prophylaxis in ureteroscopic stone removal. In addition perioperative single shot prophylaxis may be beneficial in case of an unexpected intraoperative complication like e.g. ureter perforations.     

Pediatric stone disease

Urinary stone disease is less common in children than adults. Although many aspects of pediatric stone disease are similar to that of adults, there are unique concerns regarding the presentation, diagnosis, and management of stone disease in children. We present a review of the increasing prevalence of pediatric stone disease, the diagnostic concerns specific to children, recent results from pediatric series regarding the expectant management and surgical treatment of stones, metabolic evaluation, and current research on the genetics of nephrolithiasis.     

Bare naked baskets: optimizing ureteroscopic stone extraction

Baskets placed through the working channels of flexible ureteroscopes limit mobility and irrigant flow. We describe a new technique to minimize these limitations. An unsheathed "bare naked" basket affords enhanced ureteroscopic efficacy by limiting obstruction of the working channel. We have used the technique clinically to treat stones in difficult locations successfully and to remove fragments of calculi after ureteroscopic lithotripsy.     

Routine postoperative imaging is important after ureteroscopic stone manipulation

PURPOSE: Improved fiber optics and advanced intracorporeal lithotripsy devices have significantly decreased the incidence of complications during ureteroscopic procedures. Despite recent reports suggesting that radiographic imaging may not be necessary in all individuals after routine ureteroscopy silent obstruction may develop in some, ultimately resulting in renal damage. We determined the incidence of postoperative silent obstruction at our institution and assessed the need for routine functional radiographic studies after ureteroscopy. MATERIALS AND METHODS: We retrospectively reviewed the charts of 320 patients who underwent a total of 459 ureteroscopic procedures for renal or ureteral calculi in a 3-year period. Complete followup with imaging was available for 241 patients (75%). Average patient age was 47.2 years. The variables of interest reviewed included preoperative pain, preoperative obstruction, targeted calculous site, stone-free rate, postoperative pain and postoperative obstruction. Mean followup was 5.4 months (range 2 to 43). RESULTS: A total of 241 patients with complete followup were identified in this analysis. Preoperative pain was present in 202 patients (84%) and 168 (70%) had preoperative obstruction. Overall targeted calculous clearance was successful in 73% of the patients and an additional 15.8% had residual fragments less than 4 mm. The renal, proximal or mid and distal ureteral stone-free rate was 32.1%, 81.9% and 90.5%, while in an additional 46.4%, 6.3% and 6.7% of cases, respectively, residual fragments were less than 4 mm. Of the 241 patients 30 (12.3%) had obstruction postoperatively due to residual stone in 25 (83.3%), stricture in 3 (10%), edema of the ureteral orifice in 1 (3.3%) and a retained encrusted stent in 1 (3.3%). Postoperatively obstruction correlated with postoperative pain in 23 of the 30 patients (76.7%). Pain was present postoperatively in 30 of the 211 patients (14%) without evidence of ureteral obstruction postoperatively. However, silent obstruction developed in 7 patients (23.3%) or 2.9% of the total cohort. All 7 patients underwent secondary ureteroscopy to alleviate obstruction. A single patient ultimately received chronic hemodialysis for renal failure, 1 was lost to followup and in 5 there was documented successful resolution of the cause of obstruction. CONCLUSIONS: Our analysis suggests that silent obstruction remains a potentially significant complication after stone management. Relying on postoperative pain to determine the necessity of postoperative imaging places patients at risk for progressive renal failure due to unrecognized obstruction. Therefore, we recommend that imaging of the collecting system should be performed by excretory urography, spiral computerized tomography or ultrasound within 3 months after routine ureteroscopic stone treatment to avoid the potential complications of unrecognized ureteral obstruction.     

Preoperative stenting for ureteroscopic lithotripsy for a large renal stone

A large renal stone can be treated ureteroscopically, but the treatment often requires more than one procedure. The use of stenting before ureteroscopy was recently reported. The present study investigated the effectiveness of preoperative stenting before ureteroscopic lithotripsy for large (>15 mm) renal stones. A ureteral stent was intentionally inserted in 25 patients undergoing ureteroscopic surgery. A group of 36 non‐prestented patients was used as control. Median stone diameter was 21 mm in both groups. Pre‐ureteroscopy stenting significantly improved the stone‐free rate, defined as stones <2 mm and <4 mm (P < 0.05), whereas it did not significantly improve the stone‐free rate defined as 0 mm (P = 0.12). The uretereoscopy success rate was 72.0% in the stented and 55.6% in the control group (P = 0.09). A 14/16‐Fr ureteral access sheath was successfully inserted in 94.7% of the stented patients, and 74.2% of the non‐stented patients (P < 0.05). Our findings showed that preoperative stenting is effective for dilation of the ureter, and also to facilitate the insertion of a ureteral access sheath in patients undergoing ureteroscopic lithotripsy for large renal stones.     

Adjustable electrohydraulic lithotripsy for minimally invasive ureteroscopic stone treatment]

We report on 82 ureteroscopies and electrohydraulic lithotripsies performed with small semirigid ureteroscopes with a minimum outer diameter of 6.5 F and probes of 2.4 F and 3.3 F. Prototypes of new lithotripters were employed, which incorporate infinitely variable energy within a range of 265-1382 mJ per pulse. Increased energy was provided by a rise in voltage, thus modifying the peak pressure and the initial slope of the shock wave. One third of the stones were situated in the upper ureter, 15% in the middle and 46% in the lower ureter. In 54% of these cases previous ESWL (Dornier MFL 5000) had been performed without success. Over 85% of the manipulations were performed under local anesthesia and i.v. sedation. Stone contact was achieved in 99%. Lithotripsy was fully successful in over 90%. The average energy per pulse was 450 mJ. In 7% partial disintegration was achieved and the residual stone was flushed back into the renal pelvis followed by further effective ESWL treatment. One stone had to be removed by open surgery. There were no major complications, such as perforations, due to the electrohydraulic lithotripsy itself. One perforation was caused when the endoscope was advanced into the ureter. No strictures were seen at the 6-month follow-up examination. An indwelling stent was placed in 48% of cases, as the stone burden or an inflamed stone bed suggested this was necessary. We conclude that electrohydraulic lithotripsy with adjustable energy resulting in various peak pressures of the shock wave is a safe and effective method of endoureteral stone treatment.     

Transurethral ureteroscopic extraction of stone from the ureter and renal pelvis

Use of a rigid ureteroscope for extraction of 19 ureteric and 6 renal pelvic stones is reported. One of the 24 patients had bilateral ureteric stone. The extraction was successful in 22 cases, including 9 after ultrasonic disintegration of stone. Surgical removal of stone was required because of failure of the ultrasound apparatus in one case and ureteric perforation in another. One stone was extracted "blind". The method has many advantages over more established procedures. It should be the preferred technique for management of ureteric calculi, and may be an option for some renal pelvic stones.     

改良输尿管硬镜钬激光碎石术治疗输尿管上段结石疗效观察

目的探讨使用改良的输尿管硬镜钬激光碎石术治疗输尿管上段结石的临床疗效。 方法选取2015年5月至2017年5月山西医科大学第一医院泌尿外科进行治疗的115例单侧输尿管上段单发结石（结石具体位置距肾盂输尿管连接部≤5 cm）患者,分别行改良输尿管硬镜碎石治疗（改良组,72例）和传统输尿管硬镜碎石治疗（对照组,43例）。与对照组相比,改良组输尿管硬镜进水阀与出水阀分别经三通连接进水管与负压吸引器,采取改良截石位,在封堵器的引导下置入输尿管硬镜,人工控制进水速度,利用200 μm细光纤碎石,通畅引流后小壶输注呋塞米。两组在年龄、性别、结石侧别、肾积水程度、结石距肾盂输尿管连接部距离和结石大小方面,差异无统计学意义（P>0.05）。比较两组患者的一期清石率及漂移率。 结果清石率方面,改良组为93.06％（67/72）,对照组为62.79％（27/43）,两组间差异有统计学意义（χ²=16.52,P<0.05）,漂移率方面改良组为5.56％（4/72）,对照组为41.86％（18/43）,两组间差异有统计学意义（χ²=22.94,P<0.05）,术中及术后均无输尿管穿孔、输尿管撕脱等严重并发症。 结论改良后的方法处理输尿管上段结石时,结石不易漂移入肾盂,结石一期清除率高,安全方便可行性强,尤其适用于没有输尿管软镜的基层医院。