Extracorporeal shock wave lithotripsy in the management of pediatric urolithiasis

Experience of high polymer gel pad assisted ultrasound monitoring in the treatment of infant urolithiasis during extracorporeal shock wave lithotripsy

In the extracorporeal shock wave lithotripsy for infants, we used a medical polymer gel pad to assist ultrasonic positioning, so that the ultrasonic probe could be far away from the shock wave energy field. Although not affecting the ultrasonic positioning and monitoring effect, we discussed the protective effect of this method on the ultrasonic probe. A retrospective analysis was made on 21 infants (0-3 years old) who received ESWL in our hospital from June 2021 to February 2023. After the stones were accurately located by B-ultrasound before surgery, a 4 * 5 * 10 cm medical polymer gel pad was placed between the skin and the ultrasonic probe to keep the ultrasonic probe away from the shock wave energy field. The B-ultrasonic wave source locked the target stone through the gel pad, and the lithotripter Dornier Compact Delta II was used for lithotripsy. The extracorporeal shock wave lithotripsy was completed under the whole process of B-ultrasonic monitoring. All patients completed the surgery under ultrasound monitoring, and there were no abnormalities in the ultrasound probe during the surgery. The average stone size was 0.60 ± 0.21 cm, the surgical time was 39.8 ± 13.8 min, and the total energy of lithotripsy was 7.41 ± 4.35 J. There were no obvious complications in all patients after the surgery. After 2 weeks of ultrasound examination, the success rate of lithotripsy in 21 patients reached 85.7%. We believe that the use of the gel pad increases the distance between the ultrasonic probe and the skin, leaving the probe away from the shock wave energy field, avoiding the damage of the shock wave source to the ultrasonic probe, and does not affect the monitoring effect of ultrasound on stones and the success rate of lithotripsy, which is worthy of further promotion in the field of children's urinary stones.

How well do ESWL nomograms predict treatment success in pediatric patients?

Objective:

To study was to identify the variables that influence the outcomes of pediatric SWL patients in our clinic and to compare our findings to previously published nomograms.

Methods:

All children who underwent SWL at a single center between 2005 and 2020 were included in this retrospective study. Depending upon the age and mental state of the children, SWL procedures were performed with or without anesthesia. Data from the hospital information system were obtained on patient characteristics, metabolic evaluation, imaging, SWL details, and post-procedure results, and their correlation with the Onal and Dogan nomograms was evaluated.

Results:

The present study included 112 pediatric patients in total. The average age was 8.22 ± 4.9 (83.3 ± 58.1 months, 4 months–16 years), and the median stone size was 9.5 ± 3.2 mm (4–20 mm). Even though there was quite a significant positive correlation between age and the number of shots and the intensity of shots (intensity and number of shots increased with increasing age), there was no statistical difference in the number of sessions and stone-free rates. The number of shots and sessions was significantly lower in patients with hydronephrosis ( N = 70) than in those without ( N = 42) ( p < 0.001). When the stone-free rates of patients without and with hydronephrosis were compared, it was discovered that they were 69.05% and 92.86%, respectively, which was statistically significant ( p < 0.01).

Conclusions:

It is believed that the nomograms developed for SWL in pediatric patients should be reviewed, and larger, prospective studies should be conducted.

Semirigid Ureteroscopy Therapy against Childhood Kidney Stones

Objective

The purpose of the current study was to assess the effectiveness of semirigid ureterorenoscopy (URS) as first-line therapy for early childhood patients with <20 mm stones in the pelvic, middle, or upper calices.

Methods

In all, 61 pediatric kidney stone patients who had flexible ureteroscopy (fURS) between January 1, 2010, and December 31, 2019, were included in this study. Before fURS, semirigid URS employed the UreTron or holmium: YAG (Ho : YAG) laser was conducted. When semirigid URS was unsuccessful, fURS was used for retrograde intrarenal surgery (RIRS). All participants were monitored clinically for a minimum of three months after each procedure.

Results

The patient's mean age was 4.52 ± 1.53 years, and 52 (83.61%) participants underwent semirigid URS successfully. Mean procedural duration of semirigid URS was 36.49 ± 7.72 min. The stone-free rate after semirigid URS was 92.16% (47/51). During the postprocedural medical observation, there were no serious adverse effects.

Conclusions

Based on the present study's findings, semirigid URS is a low-risk, effective therapy for kidney stones in selected pediatric patients.

Safety and efficacy of minimally invasive percutaneous nephrolithotomy for infantile nephrolithiasis. Single centre experience from Pakistan

OBJECTIVE

To assess the efficacy and safety of mini-percutaneous nephrolithotomy (PCNL) for small renal stones 1-2 cm in size in infants less than one year.

MATERIAL AND METHODS

This descriptive case series was conducted in the department of pediatric urology Institute of Kidney Diseases Peshawar, Pakistan, from March 2019 to March 2022. All the patients underwent mini-PCNL in prone position under GA with 14 Fr access sheath and 10 Fr nephroscope. Stone clearance was assessed by non-contrast CT KUB at 30th postoperative day. Patients with no residual fragments on the non-contrast CT KUB were defined as stone-free. Patients with residual fragments of any size were defined as procedure failure. Safety was determined in terms of intra and postoperative complications.

RESULTS

A total of 51 infants were included in the study. The mean age of patients was 9.6 + 1.8 (5-12 month). The mean stone size was 15.8 + 2.7 (10-21) mm in length and 12.3 + 2.2 (8-17) mm in width. PCNL mean operative time was 51.6 ± 7.1 (40-70) minutes. Complete stone clearance at one month was observed in 46 (90.2%) patients. Residual fragments were seen in 5(9.8%) patients with a mean size of 1.6 + 0.4 (0.9-2.0) mm. None of the patients required any additional procedure for clearance of stones. In 7 (13.7%) patients, some post-operative complications were observe, all were grade I complications, including fever in 5(9.8%) and transient hematuria in 2(3.9%) patients.

CONCLUSION

Mini-PCNL is a safe and effective treatment for renal stones in infants measuring 1-2 cm with high SFR and an acceptable complication rate.

Extracorporeal shock wave lithotripsy in Indian children: Predictors of outcome and validation of pre-treatment nomograms

BACKGROUND

Although multiple variables have been shown to affect outcomes in pediatric lithotripsy (ESWL), there is no consensus on the same. Nomograms combine multiple variables and provide an objective prediction of outcomes. Two nomograms have been previously described and validated in two studies from the same geographical area. External validation in multiple settings is needed, as a nomogram's performance may vary with time, geographical area and clinical scenario.

OBJECTIVES

This study aimed to identify variables influencing pediatric ESWL outcomes, validate published nomograms and describe the clinical and metabolic profile of Indian children treated with ESWL.

DESIGN

This retrospective cohort study included all children who underwent ESWL from 2002 to 2019 at a single centre. ESWL was performed under general anaesthesia. Mid and lower ureteric calculi were treated in prone and the rest in supine position. 1500-2000 shocks were delivered at a voltage of 12-16 kV. Data pertaining to patient characteristics, metabolic evaluation, imaging, ESWL details and post-procedure outcomes were obtained from the hospital information system and these variables, along with Onal and Doğan scores, were correlated with stone clearance. Cut-offs for Onal and Doğan scores were determined using receiver operator characteristic (ROC) curve analysis and compared with area under the curve (AUC). Complications, ancillary procedures and metabolic abnormalities were recorded.

RESULTS

A total of 66 children (76 renal units) were included. Mean age was 5.5 years (Range 6 months-14 years) and median stone size, 12 mm (IQR 9, 15.25). Average treatment sessions were 1.8 ± 0.99. Median shocks in the stone-free group and those who failed treatment were 1750 (IQR 1500, 3000) and 3250 (IQR 1750, 4750) respectively. The remaining variables are depicted in Table 1. The stone free rate was 63.2%. Fragments <4 mm were seen in 19 (25%). Efficacy Quotient was 40. The AUC for Doğan nomogram (cut-off <199.5) was 0.761 while that for Onal nomogram (cut-off <2.5) was 0.762 and 0.771 after one and three shocks respectively. On multivariate analysis, age, multiple calculi, Onal and Doğan scores were predictive of clearance. Doğan score had higher specificity. Complications were seen in 16 (21%) and ancillary procedures needed in 7 (9.2%). Metabolic abnormalities were seen in 84.8%, the commonest being hyperoxaluria. Mixed stones were most frequent.

CONCLUSIONS

Lithotripsy in children is safe and effective. Older age, presence of multiple calculi, higher Onal and Doğan scores are predictive of treatment failure.

Update on Surgical Management of Pediatric Urolithiasis

Urolithiasis has always been a fascinating disease, even more so in children. There are many intriguing facets to this pathology. This article is a nonsystematic review to provide an update on the surgical management of pediatric urolithiasis. It highlights the pros and cons of various minimally invasive surgical options such as extracorporeal shockwave lithotripsy (ESWL), retrograde intrarenal surgery (RIRS), percutaneous nephrolithotomy (PCNL), laparoscopy, and robotics. This article also describes the various intracorporeal disintegration technologies available to fragment the stone, including the newer advancements in laser technology. It also emphasizes the cost considerations especially with reference to the emerging economies. Thus, this manuscript guides how to select the least-invasive option for an individual patient, considering age and gender; stone size, location, and composition; and facilities and expertise available.

Comparison of Extracorporeal Shock Wave Lithotripsy for Urolithiasis Between Children and Adults: A Single Centre Study

Objective

To retrospectively evaluate the effectiveness of extracorporeal shock wave lithotripsy (ESWL) for urolithiasis and compare the results between children and adults.

Materials and methods

From January 2011 to January 2015 (four years), ESWL was performed in 104 children and 300 adults for urolithiasis. MODULITH^® SLX-F2 lithotripter (Storz Medical AG, Tägerwilen, Switzerland) equipment was used for ESWL. The stone-free rates, the number of ESWL sessions required, complication rates and ancillary procedures used were evaluated in a comparative manner.

Results

The mean age ± standard deviation (SD) of children was 7.84±4.22 years and of adults was a 40.22±1.57 years. Mean ± SD of the stone size was 1.28±61 cm in the adults while 1.08 ± 0.59 cm in the children. In adults, the complications included steinstrasse in six (1.98%) patients, fever in 15 (4.95%), hematuria in 19 (6.28%) and sepsis in six (1.98%) patients. In children, steinstrasse was observed in two (1.9%), mild fever in two (1.9%), hematuria in six (5.7%) and sepsis was seen in four (3.8%) patients. The overall complication rate in the adults and in the children, it was found to be 46/300 (15%) and in the children, it was seen to be 14/104 (13%). No statistical difference was found in post-ESWL complications between children and adults (P>0.05). Ancillary procedures including double J (DJ) stent were used in 13 (12.5%) children and 87 (29%) adults. There was a better stone clearance rate in children i.e. 79% as compared to 68% in adults (X²: P=0.036).

Conclusion

Children can achieve high stone-free rates after ESWL with a lower need for repeat ancillary procedures as compared to adults. However, there is a difference in the post-ESWL complications between these groups.

Effect of size and site on the outcome of extracorporeal shock wave lithotripsy of proximal urinary stones in children

OBJECTIVE

To determine the effect of location and size of stones on the outcome of extracorporeal shock wave lithotripsy (ESWL) in children.

PATIENTS AND METHODS

In 2008-2010, 150 children (median age 6.6 years) with radio-opaque ureteric and renal stones measuring ≤4 cm were treated. Exclusion criteria were coagulation disorders, pyelonephritis, distal obstruction, non-functioning kidney and hypertension. ESWL was performed under general anesthesia. Follow up period was 5-22 months.

RESULTS

186 stones were treated: 76 calyceal, 92 pelvic and 18 proximal ureteral. Mean stone size was 1.3 cm. A total of 312 sessions were performed (mean per stone = 1.67 sessions). The mean number of shock waves per session was 2423.68. Overall stone-free rate was 89.24%. Having a calyceal location did not significantly affect the stone-free rate (p = 0.133). The failure rate was significantly higher (66.7%) in stones >3 cm in size (p < 0.001). Complications were encountered in 18 patients; 2 underwent auxillary ureteroscopy and 4 uretrolithotomy for treatment of steinstrasse.

CONCLUSION

ESWL is a safe and effective method for treatment of stones up to 2 cm in children. Rate of auxillary procedures increases in stones >2 cm in size. About 80% of failures were associated with stone size >1.35 cm while 52.3% of completely cleared stones were associated with size <1.35 cm.

Extracorporeal shock wave lithotripsy is effective in treating single melamine induced urolithiasis in infants and young children

PURPOSE

We evaluated the safety and efficacy of extracorporeal shock wave lithotripsy in the treatment of single melamine induced urolithiasis in infants and young children.

MATERIALS AND METHODS

A total of 189 infants and young children with single melamine induced urolithiasis were referred to our center for treatment with extracorporeal shock wave lithotripsy between March 2009 and July 2010. Location of the calculus was proximal ureteral in 17 patients, mid ureteral in 5, distal ureteral in 26 and kidney in 141. Stone size ranged from 3.8 to 25 mm (mean ± SD 9.79 ± 3.83).

RESULTS

All patients underwent extracorporeal shock wave lithotripsy using the same device with an energy ranging from 8 to 12 kV. Stone-free rate was 97.88%, clinically insignificant residual fragment rate was 1.59% and repeat treatment rate was 2.65%. A total of 180 patients (95.24%) required only 1 lithotripsy session and 5 (2.65%) required 2 sessions. Mean ± SD number of shock waves delivered per session was 580.36 ± 190.69 (range 65 to 950). Extracorporeal shock wave lithotripsy failed to fragment stones in only 1 infant, who had a proximal ureteral stone. A total of 181 specimens were collected and analyzed by infrared spectrum, with results demonstrating that the main composition was uric acid and melamine. All patients were followed for a mean of 28 months (range 20 to 36). No severe complication, such as renal subcapsular hemorrhage, hypertension, kidney rupture or lung injury, was observed.

CONCLUSIONS

Extracorporeal shock wave lithotripsy with low energy can effectively disintegrate melamine induced calculi. This approach has become our preferred method for treating single melamine induced urolithiasis in infants and young children.

The effects of hydronephrosis and stone burden on success rates of shockwave lithotripsy in pediatric population

OBJECTIVES

To evaluate the efficacy of shockwave lithotripsy (SWL) with a third-generation SWL machine in the pediatric age group and to determine the effects of stone burden and the degree of hydronephrosis on the results.

METHODS

Two hundred and sixty children with urinary system stones were treated with Siemens Lithostar Modularis Uro-Plus. The patients were divided into three groups according to stone burden (group 1: <100 mm(2); group 2: 101-200 mm(2); group 3: >200 mm(2)) and into four groups according to the degree of hydronephrosis (group 0: absent; group 1: mild; group 2: moderate; group 3: severe). These groups were compared in terms of the success rate of SWL.

RESULTS

Two hundred and seventy-nine renoureteral units of 260 patients were treated with 402 SWL sessions. The average stone burden was 98.2 mm(2) (range: 11-525). The overall success rate was 87.5%. According to stone burden, the success rate was 93.1% in group 1, 85.5% in group 2, and 60% in group 3 (p < 0.001). According to the degree of hydronephrosis, the success rate was 93.8% in group 0, 89.6% in group 1, 73.3% in group 2, and 64.3% in group 3 (p < 0.001). The average energy, number of shockwaves, number of sessions, retreatment rate, auxiliary procedure rate, and overall efficacy quotient were 1.76 units, 2260, 1.4, 33%, 8.2%, and 0.62, respectively.

CONCLUSION

SWL is an effective treatment method in selected patients in pediatric age group. However, percutaneous nephrolithotomy can be the first alternative for stones larger than 200 mm(2). It should also be kept in mind that the success rate of SWL decreases when the degree of hydronephrosis increases.

Does the type of lithotripter affect outcomes in children with upper tract urolithiasis?

PURPOSE

To compare the treatment outcome and short-term safety of electrohydraulic and electromagnetic lithotripters in children.

PATIENTS AND METHODS

Comparative analysis of children undergoing shockwave lithotripsy (SWL) with a Dornier MPL 9000 electrohydraulic lithotripter (EHL) and a Siemens Modularis electromagnetic lithotripter (EML) was performed. All SWL treatments were performed by a single operator under the supervision of an admitting urologist. The demographic features, stone, and treatment-related parameters, including complications, were analyzed for both groups. Stone-free (SF) rates, re-treatment rate, and efficiency quotient (EQ) were calculated and compared for the two groups.

RESULTS

Ninety-eight children had SWL for renal and proximal ureteral stones. There were 58 children in the EHL group and 40 in the EML group. There were no statistically significant differences between the groups in terms of age, sex, type of anesthesia, diagnostic modality, site, side, and size of the stones. Number of shockwaves used with EML was greater than with EHL (P < 0.00). SF rate was 95% and 77% for EHL and EML, respectively, with a statistically significant difference (P < 0.00). The re-treatment rate was equal in either group. The complication rate was higher with the EHL compared with the EML, although it did not reach statistical significance. Steinstrasse was the most common complication noted. EQ was 66% for the EHL, in comparison with 53% for the EML.

CONCLUSION

The EHL has a better SF and EQ than the EML; however, short-term safety is marginally better with the EML.

Shock wave lithotripsy is effective and safe for distal ureteral calculi in children

We evaluated the effectiveness of the Siemens Lithostar Modularis lithotriptor for the management of distal ureteric calculi in children. Between 2004 and 2006, 29 children with distal ureteric calculi were treated in our stone center with the Siemens Lithostar Modularis (Siemens Medical Solutions, Inc.) Effectiveness of lithotripsy, retreatment and efficacy quotient rates, and complications were assessed. The series consisted of 18 (62%) boys and 11 (38%) girls with an age range of 1-13 years (average age 7.0 +/- 3.5). Under fluoroscopic guidance, children were treated with a maximum 3,000 shocks at an average of 2.2 +/- 0.3 kV. Mean stone size was 8.2 +/- 3.2 mm (range 4-18). Success was defined as the lack of any visible stone fragments on posttreatment radiological evaluation. The mean number of sessions required was 1.5 +/- 0.8/patient (range 1-4). Complete clearance rate at 3 months was 86.2%. Re-treatment and efficacy quotient rates for distal ureteral stones were 41.4 and 55.6%, respectively. Complications such as urinary tract infection or steinstrasse occurred in 2 (6.9%) patients. Minor complications included petechial skin hemorrhage at the site of entry of shock waves in all patients. Our results show that shock wave lithotripsy for distal ureteral calculi with the Siemens Lithostar Modularis lithotriptor has a high success rate (86.2%) and efficacy quotient (55.6%) with negligible complications in children.