Extracorporal shock wave lithotripsy in the management of stones in children with oxalosis—still the first choice?

Background

Primary hyperoxaluria (PH) is a recognised cause of nephrolithiasis. The aim of this study was to evaluate the success of extracorporal shock wave lithotripsy (ESWL) in treating nephrolithiasis in children with PH.

Methods

This was a retrospective review of patient characteristics, treatments and outcomes of 36 children with oxalate stones due to PH.

Results

A total of 52 stones were formed in 28 patients, of which 23 stones were treated with ESWL. Of these 23 stones, ten improved and 13 did not; nine were located in the upper pole, nine in the lower pole and four and one in the pelvic and ureteric areas, respectively. All pelvic and ureteric stones improved, while 66.7 % of upper pole stones and 89.9 % of lower pole stones did not; 20 % of PH type 1 stones improved compared to 47 % of PH type 2 stones. The mean pre- and post-eGFR in stone-improvers was 98.82 and 104.7 ml/min/1.73 m², respectively; in the non-improvers, these values were 100.75 and 95.68 ml/min/1.73 m², respectively. Mean pre-ESWL stone size in the improved and non-improved groups was 7.3 mm and 8.5 mm respectively.

Conclusions

Based on our results, ESWL is not the ideal method of stone therapy for patients with PH. ESWL was more effective in treating pelvic and ureteric stones, with upper pole stone response being better than lower pole response. PH2 patients were more than twice as likely to respond to ESWL treatment. Stone size and prior preventive treatment did not affect outcome. eGFR was not affected by ESWL.     

Flexible ureterorenoscopy versus extracorporeal shock wave lithotripsy for treatment of lower pole stones of 10-20 mm

Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Shock wave lithotripsy and flexible ureterorenoscopy are acceptable treatment options for lower pole stones smaller than 10 mm, while percutaneous nephrolithotomy is the favoured treatment for stones larger than 20 mm. For treatment of lower pole stones of 10–20 mm, flexible ureterorenoscopy has a significantly higher stone‐free rate and lower retreatment rate than shock wave lithotripsy.

OBJECTIVE

• ? To compare the outcomes of flexible ureterorenoscopy (F‐URS) and extracorporeal shock wave lithotripsy (ESWL) for treatment of lower pole stones of 10–20 mm.

PATIENTS AND METHODS

• ? The database of patients with a single lower pole stone of 10–20 mm was examined to obtain two matched groups who were treated with F‐URS or ESWL. Matching criteria were stone length, side and patient gender.
• ? Stone‐free rates were evaluated 3 months after the last treatment session by non‐contrast computed tomography. Both groups were compared for retreatment rate, complications and stone‐free rate.

RESULTS

• ? The matched groups included 37 patients who underwent F‐URS and 62 patients who underwent ESWL. Retreatment rate was significantly higher for ESWL (60% vs 8%, P < 0.001).
• ? Complications were more after F‐URS (13.5% vs 4.8%), but the difference was not significant (P= 0.146). All complications were grade II or IIIa on modified Clavien classification.
• ? The stone‐free rate was significantly better after F‐URS (86.5% vs 67.7%, P= 0.038). One failure of F‐URS (2.7%) and five failures (8%) of ESWL were treated with percutaneous nephrolithotomy.
• ? Significant residual fragments in three patients (8%) after F‐URS were treated with ESWL, while significant residual fragments after ESWL in five patients (8%) were treated with F‐URS. Residual fragments (<4 mm) were followed every 3 months in one patient (2.7%) after F‐URS and in 10 patients (16%) after ESWL.

CONCLUSIONS

• ? For treatment of lower pole stones of 10–20 mm, F‐URS provided significantly higher stone‐free rate and lower retreatment rate compared with ESWL.
• ? The incidence of complications after F‐URS was not significantly more than after ESWL.

     

Is extracorporeal shock wave lithotripsy in pediatrics a safe procedure?

Removal of urinary calculi is an essential element in the successful treatment of patients with urinary stone disease. The new generation of lithotriptors allows the treatment without the need for general anesthesia. The patients, often outpatients, have a faster discharge from the hospital with a reduction of hospitalization time and operating costs. Shock wave lithotripsy (SWL) is currently considered a safe technique for treatment of pediatric urinary lithiasias, with a low percentage of complications and subsequent surgical retreatments. But can we define SWL as a safe procedure in pediatrics? Herein, we will review the literature to justify SWL safety in children, focusing on important parameters as the insertion of preoperative stenting, side effects, and complications after the procedure.     

Does a slower treatment rate impact the efficacy of extracorporeal shock wave lithotripsy for solitary kidney or ureteral stones?

PURPOSE: We compared the efficacy of an SR (70 to 80 shocks per minute) and an FR (120 shocks per minute) for ESWL for solitary stones less than 2 cm located in the kidney or proximal ureter. MATERIALS AND METHODS: A total of 349 patients with a solitary, radiopaque kidney or ureteral stone underwent ESWL on a DoLi(R) 50 lithotriptor. Patients were grouped based on stone size, stone location and whether SR or FR treatment was performed. Of the 349 patients 135 had a renal stone between 1and 2 cm, 137 had a renal stone less than 1 cm and 77 had a proximal ureteral stone with a surface area of between 30 and 90 mm. SFRs were determined at approximately 1 month by plain x-ray of the kidneys, ureters and bladder. RESULTS: In comparison to the FR groups SR groups required fewer shocks and had significantly lower power indexes. Of patients with renal stones between 1 and 2 cm 24 of 52 (46%) in the FR group were stone-free compared to 56 of 83 (67%) in the SR group (p <0.05). For stones with a surface area of 30 to 90 mm located in the kidney or proximal ureter there was a trend toward an improved SFR in the SR group but differences between the SR and FR groups were not statistically significant. CONCLUSIONS: For solitary renal stones between 1 and 2 cm an SR results in a better treatment outcome than an FR for ESWL. However, when stone size is less than 1 cm, SFR differences in the SR and FR treatment groups become less significant.     

Is lower pole caliceal anatomy predictive of extracorporeal shock wave lithotripsy success for primary lower pole kidney stones?

PURPOSE: The management of lower pole kidney stones is controversial. We examined whether lower pole caliceal anatomy could predict the success of extracorporeal shock wave lithotripsy of primary lower pole kidney stones 20 mm. or less. MATERIALS AND METHODS: From December 1997 to June 2001, 246 adults with a single, 20 mm. or less radiopaque lower pole renal stone were treated with the Doli 50 lithotriptor (Dornier Medical Systems, Marietta, Georgia) while under general anesthesia. Of the 246 patients 190 (77%) had excretory urography available for review. Lower pole infundibular length and width, lower pole infundibulopelvic angle and caliceal-pelvic height were measurable on 161 (85%), 129 (68%), 128 (67%) and 163 (86%) excretory urograms, respectively. Extracorporeal shock wave lithotripsy was considered a failure if residual stone fragments remained after 1 month, or an auxiliary procedure or re-treatment was required.RESULTS The overall stone-free rate was 78% (32 of 41) for stones 5 mm. or less, 73% (98 of 135) for stones 6 to 10 mm., 43% (22 of 51) for stones 11 to 15 mm. and 30% (7 of 19) for stones 16 to 20 mm. in maximum linear dimension. The stone-free rates grouped according to stone surface area were 76% (48 of 63 stones) for stone surface area 25 mm.2 or less, 69% (97 of 141) for 26 to 100 mm.2 and 33% (14 of 42) for 101 to 400 mm.2. Caliceal anatomy was not predictive of success even with stones grouped as 10 or less or 11 to 20 mm. Grouping patients with favorable (lower pole infundibulopelvic angle 70 degrees or greater, lower pole infundibular length 30 mm. or less and lower pole infundibular width greater than 5 mm.) versus unfavorable (70 degrees or less, greater than 30 mm. and 5 mm. or less, respectively) anatomy was also not predictive of success. CONCLUSIONS: On the Doli 50 machine stone size rather than caliceal anatomy is predictive of treatment outcome. Initial treatment failures with this machine should be managed by alternative endoscopic procedures if necessary rather than by repeat shock wave lithotripsy.     

Removal of ureteral stones with extracorporeal shock wave lithotripsy and ureteroscopic procedures. What can we learn from the literature in terms of results and treatment efforts?

A literature review was made to obtain information on the treatment efforts required for a successful removal of ureteral stones when extracorporeal shock wave lithotripsy (ESWL) or ureteroscopic stone extraction or disintegration (URS) were used as primary procedures. Data were collected from 59 reports on ESWL and 23 on URS. The study thereby comprised 20,659 patients primarily treated with ESWL and 5,520 treated with URS. A treatment index (TI) was formulated from the total number of patients (N(TOT)), the number of stone free patients (N(SF)), the number of patients with retreatment (N(RE)), auxiliary procedures (N(AUX)) and general or regional anaesthesia (N(ANE)). The difference between the TI and the efficiency quotients normally used was the incorporation of the factor N(ANE) that reflected the need for general or regional anaesthesia. TI had the following form: TI = N(SF)/(N(TOT) + N(RE) + N(AUX) + N(ANE). When the groups of treated patients were considered in this way, TI was significantly higher for the patients treated with ESWL than for those treated with URS (P = 0.007). The median (range) for the groups of ESWL-treated patients was 0.50 (0.25-0.90) and for patients treated with URS 0.42 (0.26-0.94). For the combined groups of patients, the TI-values were 0.54 and 0.40, respectively. Although the average retreatment for URS was only 2.2% compared with 12.1 percent for ESWL, the need for general/regional anaesthesia was 94.3% and 28.3% in the two groups, respectively. The advantage of a lower rate of retreatment in patients primarily referred to URS was thus obviously counterbalanced by the much higher need for anaesthesia. For ureteral stones treated with ESWL in the author's department using Dornier HM3, MFL 5000, and Modulith SLX lithotripters, stone free rates of 96%, 97% an 95% were associated with TI-values of 0.61, 0.60 and 0.63, respectively. Both ESWL and URS are excellent procedures for the removal of stones from the ureter. In addition to the different degrees of invasiveness, the need for anaesthesia has to be considered in an objective comparison of the two methods.     

Is the pediatric ureter as efficient as the adult ureter in transporting fragments following extracorporeal shock wave lithotripsy for renal calculi larger than 10 mm.?

PURPOSE: We determined whether the thin ureter of the young child transports stone fragments after extracorporeal shockwave lithotripsy (ESWL) as efficiently as the adult ureter does. This determination was done by comparing the outcome after lithotripsy of renal stones greater than 10 mm. between young children and adults. MATERIALS AND METHODS: Our study group consisted of 38 children 6 months to 6 years old (median 3 years) with renal stones greater than 10 mm. in diameter. This group was further divided into 3 subgroups according to the longest stone diameter on plain abdominal film. There were 21 children with a renal stone diameter of 10 to 15 mm. (subgroup 1), 8, 16 to 20 mm. (subgroup 2) and 9 greater than 20 mm. (subgroup 3). The control group consisted of 38 adults older than 20 years randomly selected from the local ESWL registry. Each adult was matched with a child regarding stone diameter and localization. The control group was similarly divided into subgroups 1a, 2a and 3a. ESWL was performed with the unmodified Dornier HM-3 lithotriptor (Dornier Medical Systems, Inc., Marietta, Georgia). The stone-free rate, complication rate, and need for tubes, including stent or nephrostomy, and greater than 1 ESWL session were compared. RESULTS: The stone-free rate was 95% in the study and 78.9% in the control group (p = 0.086). Stone-free rates were 95%, 100% and 89% in subgroups 1, 2 and 3, and 95%, 65% and 56% in subgroups 1a, 2a and 3a, respectively. There were 10 children and 4 adults who underwent greater than 1 ESWL session (p = 0.14). Then there were 10 children and 6 adults who required a tube before ESWL (p = 0.04), and almost all of them were included in subgroups 3 and 3a. Early complications were rare in both the study and control groups. Late complications had included 2 cases of Steinstrasse in the control and none in the study group. CONCLUSIONS: The stone-free rate after ESWL for large renal stones is higher in young children compared to adults with matching stone size. Renal stones greater than 20 mm. often require more than 1 ESWL session. The pediatric ureter is at least as efficient as the adult for transporting stone fragments after ESWL.     

Is extracorporeal shock wave lithotripsy the preferred treatment option for elderly patients with urinary stone? A multivariate analysis of the effect of patient age on treatment outcome

OBJECTIVES: To investigate the effect of patient age on the stone-free rate (SFR) in patients with urinary calculi treated by extracorporeal shockwave lithotripsy (ESWL). PATIENTS AND METHODS: In all, 2192 solitary radio-opaque urinary stones of 5-15 mm were identified in adult patients receiving primary ESWL. Patients were divided into three age groups, i.e. < or = 40, 41-60 and >60 years (579, 1026 and 587 patients, respectively). Multiple logistic regression was used to assess the effect of age and other possible predicting factors (gender, stone characteristics, e.g. side, site and size, and the type of lithotripter used) on the SFR at 3 months after treatment. RESULTS: The overall adjusted odds ratios (95% confidence interval) for the SFR for those aged 41-60 and >60 years (taking those aged < or= 40 years as the reference) were 0.708 (0.573-0.875; P = 0.001) and 0.643 (0.506-0.818; P < 0.001). However, if the patients were divided into those with renal or ureteric stones, only the SFR of the former was affected by age, and the adjusted odds ratios were 0.665 (0.512-0.864; P = 0.002) and 0.629 (0.470-0.841; P = 0.002), respectively. Ageing had no effect on the SFR for ureteric stones. CONCLUSION: The SFR after ESWL for renal stones, but not ureteric stones, was significantly lower in older patients. Further studies on the effects of ageing on renal stone clearance after ESWL are needed to improve stone management in the elderly population.     

Is quantitative diffusion-weighted MRI a valuable technique for the detection of changes in kidneys after extracorporeal shock wave lithotripsy?

Objective

The aim of this study was to evaluate the capability and the reliability of diffusion-weighted imaging (DWI) in the changes of kidneys occurring after extracorporeal shock wave lithotripsy (ESWL) treatment for renal stones.

Materials and Methods

A total of 32 patients who underwent ESWL treatment for renal stone disease between June and December 2011 were enrolled in this prospective study. Color Doppler ultrasonography (CDUS) and DWI were performed before and within 24 hours after ESWL. DWI was obtained with b factors of 0, 500 and 1000 s/mm² at 1.5 T MRI. Each of Resistive index (RI) and ADC values were calculated from the three regions of renal upper, middle and lower zones for both of the affected and contralateral kidneys. Paired sample t test was used for statistical analyses.

Results

After ESWL, the treated kidneys had statistically significant lower ADC values in all different regions compared with previous renal images. The best discriminative parameter was signal intensity with a b value of 1000 s/mm². The changes of DWI after ESWL were noteworthy in the middle of the treated kidney (p<0.01). There were no significant difference between RI values in all regions of treated and contralateral kidneys before and after treatment with ESWL (p>0.05).

Conclusion

DWI is a valuable technique enables the detection of changes in DWI after ESWL treatment that may provide useful information in prediction of renal damage by shock waves, even CDUS is normal.     

Spiral stent versus standard stent in patients with midsize renal stones treated with extracorporeal shock wave lithotripsy: which stent works better? A prospective randomized trial

PURPOSE: It has been proposed that stone fragment clearance with a new spiral Double-J stent (Medical Engineering Corp., New York, New York) is faster than with a standard Double-J stent. Therefore, we evaluated stent insertion, peri-interventional complications, as well as stone clearance in patients with midsize kidney stones treated with extracorporeal shock wave lithotripsy (3,500 shock waves) in a prospective randomized trial. MATERIALS AND METHODS: A total of 32 patients were randomized for preoperative insertion of a spiral stent (16) or a standard stent (16). Stone volume was measured from an abdominal plain film. Stent inserting time and stent handling problems, as well as perioperative and postoperative complications were evaluated. Clearance of stone fragments was analyzed by abdominal plain films and ultrasound on day 1, and at the end of weeks 1, 2 and 6 after treatment or until stone fragments were completely cleared. RESULTS: Median stone volume was 1.8 ccm (range 0.4 to 5.2) in the spiral stent group and 1.3 ccm (range 0.4 to 2.6) in the standard stent group (p = 0.08). Median stent inserting time was 21 minutes (range 10 to 60) in the spiral stent and 18 minutes (range 5 to 45) in the standard stent group (p = 0.94). Inserting difficulties occurred in 6 of 16 (38%) patients with spiral stents and in none with standard stents (p = 0.005). Spontaneous stent displacement occurred in 4 of 16 patients in the spiral stent group and did not occur in the standard stent group (p = 0.03). The percentage of stone-free patients 1 day, and 1, 2 and 6 weeks after treatment was 0%, 13%, 44% and 81% in the spiral stent group and 6%, 19%, 50% and 88% (p = 0.64) in the standard stent group, respectively. CONCLUSIONS: Spiral stents are more difficult to insert, spontaneously dislocate more often and have no advantage in overall stone clearance compared with standard stents.     

Is ERCP manometry useful in the choice of treatment of stones of the common bile duct?

Summary To verify the appropriateness of sphincterotomy as the treatment of choice of choledocholithiasis, since 1980 we have been using endoscopic retrograde cholangiopancreatographic (ERCP) manometry of the sphincter of Oddi (SO). This method allows direct investigation of SO motor activity and provides useful information regarding the presence of benign papillary stenosis (BPS). Thirty-four patients were investigated because the radiological examination indicated BPS might be present. Of these, 20 had common bile duct (CBD) stones, while the remaining 14 presented with biliarylike pain and one or more of the following: CBD dilation (larger than 12 mm); emptying of the ERCP contrast medium took longer than 45 min; abnormal liver function tests. Moreover, 8 healthy volunteers served as controls. Our results show that the incidence of SO motor anomalies is very low in the presence of choledocholithiasis, while it is substantial in patients with suspected SO dysfunction. These observations would suggest that, unlike the traditional view, BPS is rarely secondary to biliary lithiasis. Therefore, most of the sphincterotomies performed that are based on the assumption of underlying SO pathology should be considered unnecessary. Under these circumstances, the physiological role of a functioning SO has induced us to advocate sphincterotomy, surgical or endoscopic, in selected cases only.     

Can Phyllanthus niruri affect the efficacy of extracorporeal shock wave lithotripsy for renal stones? A randomized, prospective, long-term study

PURPOSE: Phyllanthus niruri is a plant used in Brazilian folk medicine for the treatment of urolithiasis. We assessed the efficacy of P. niruri after extracorporeal shock wave lithotripsy for renal stones. MATERIALS AND METHODS: We prospectively evaluated 150 patients with renal stones that were as large as 25 mm and composed of calcium oxalate. All patients received 1 to 3 extracorporeal shock wave lithotripsy sessions by Dornier Lithotriptor S. After treatment 78 of 150 patients (52%) underwent therapy with Uriston, a P. niruri extract (2 gm daily) for at least 3 months (group 1). Otherwise 72 of 150 patients (48%) were used as a control group (group 2). No significant difference in stone size between the 2 groups was found. Stone clearance was assessed after 30, 60, 90 and 180 days by abdominal x-ray and ultrasound scan. RESULTS: Stone-free rate (stone-free defined as the absence of any stone or residual fragments less than 3 mm) was 93.5% in group 1 and 83.3% in group 2 (p = 0.48) at the end point of the followup (180 days). For lower caliceal stones (56 patients) the stone-free rate was 93.7% in the treatment group and 70.8% in the control group (p = 0.01). Re-treatment need for group 1 was 39.7% and for group 2 it was 43.3% (p = 0.2). No side effects were recorded with extracorporeal shock wave lithotripsy or P. niruri therapy. CONCLUSIONS: Regular self-administration of P. niruri after extracorporeal shock wave lithotripsy for renal stones results in an increased stone-free rate that appears statistically significant for lower caliceal location. Its efficacy and the absolute lack of side effects make this therapy suitable to improve overall outcomes after extracorporeal shock wave lithotripsy for lower pole stones.     

How effective is extracorporeal shock wave lithotripsy of ureteral stones with Dornier Lithotripter S EMSE 220F-XXP? A prospective and preliminary assessment

Aim  

To report our preliminary series with the Doli S EMSE 220F-XXP, the upgraded version of the previous Dornier Lithotripter S EMSE 220, for treatment of ureteral stones.     

Is there a role for tamsulosin in shock wave lithotripsy for renal and ureteral calculi?

PURPOSE: We evaluated the effect of the alpha-blocker tamsulosin on stone clearance, analgesic requirements and steinstrasse in shock wave lithotripsy for solitary renal and ureteral calculus. MATERIALS AND METHODS: A prospective, double-blind, randomized placebo controlled study was performed during 1 year involving 60 patients with a solitary renal or ureteral calculus undergoing shock wave lithotripsy. The control group (30) received 0.4 mg tamsulosin and the study group (30) received placebo daily until stone clearance or for a maximum of 30 days. An oral preparation of dextropropoxyphene hydrochloride and acetaminophen was the analgesic used on an on-demand basis. The parameters assessed were stone size, position, clearance time, effect on steinstrasse and analgesic requirement. RESULTS: The overall clearance rate was 96.6% (28 of 29) in the study group and 79.3% (23 of 29) in the control group (p = 0.04). With larger stones 11 to 24 mm the difference in the clearance rate was significant (p = 0.03) but not so with the smaller stones 6 to 10 mm (p = 0.35). The average dose of analgesic used was lower with tamsulosin than with controls, without statistical significance. Steinstrasse resolved spontaneously in the tamsulosin group whereas 25% (2 of 8) required intervention in the placebo group. There was no difference between the 2 groups with regard to age, stone size or location. CONCLUSIONS: The alpha-blocker tamsulosin seemed to facilitate stone clearance, particularly with larger stones during shock wave lithotripsy for renal and ureteral calculus. It also appeared to improve the outcome of steinstrasse. Tamsulosin may have a potential role in routine shock wave lithotripsy.