SWL in lower calyceal calculi: evaluation of the treatment results in children and adults

Factors related to the success rate of pediatric extracorporeal shock wave lithotripsy (ESWL) in Cipto Mangunkusumo Hospital: an 8-year single-center experience

Background

ESWL is still considered as the first favorable therapeutic option for urinary stone disease with acceptable effectivity. However, factors associated with favorable outcome have not been widely studied in pediatrics due to the small number of urinary stone prevalence. The aim of this study is to evaluate the factors associated with the success rate of pediatric ESWL in our center according to immediate stone-free rate and 3-month stone-free rates.

Methods

This is a retrospective cohort study of children less than 18 years who had ESWL for urolithiasis from January 2008 until August 2015. Patient’s characteristics including age, gender, BMI, stone location, stone length, stone burden, stone opacity, and number of ESWL sessions were gathered from the medical record. Nutritional status was determined according to the Centers for Disease Control and Prevention BMI curve. The outcome of this study was the factors related to the success rate in pediatric ESWL.

Results

Extracorporeal shock wave lithotripsy was done for 36 patients and 39 renal units (RUs) with mean age of 13.7 ± 4.3 years old, height of 1480 ± 16.0 cm, and BMI of 20.0 ± 3. Of 36 patients included, 39 renoureteral units (RUs) and 46 ESWL sessions were recorded. The mean overall treatment was 1.2 ± 0.5 sessions with mean stone length of 11.1 ± 6.3 mm and stone burden of 116.6 ± 130.3 mm2. Within 3 months of follow-up, we recorded that the overall 3-month success rate was 100%, while the overall 3-month stone-free rate was 66.7%. Stone length (p < 0.001 and p < 0.001), stone perpendicular length (p < 0.001 and p < 0.001), and stone burden (p < 0.001 and p = 0.001) were found to be significantly associated with immediate success and 3-month stone-free status, respectively.

Conclusions

ESWL is an effective and safe modality to treat pediatric urolithiasis cases. Stone length, stone perpendicular length, and stone burden were found to be associated with immediate success and 3-month stone-free status after pediatric ESWL treatment.

Extracorporeal Shock Wave Lithotripsy and Combined Therapy in Children: Efficacy and Long-Term Results

Background: Extracorporeal shock wave lithotripsy (ESWL) is nowadays the first choice for the treatment of upper urinary tract stones smaller than 2 cm, considering its low complications and high success rate. Aim: To present an update of the current situation of ESWL treatment and to analyse our series of patients and the efficacy of combined lithiasis treatment in different locations and sizes. Patients and Method: Retrospective study including patients with urolithiasis treated with ESWL between 2007 and 2019. Collected data included: gender and age at treatment, presentation symptoms, imaging studies, stone location and size, complications and stone clearance. Success was defined as stone-free status or the presence of clinically insignificant residual fragments (<4 mm after 3 months follow-up). Patients with residual stones larger than 4 mm after 3 months were programmed for another ESWL session or received a combined sandwich therapy, followed by URS or percutaneous approach. Results: Between 2007 and 2019, 37 patients presented a total of 41 lithiasis episodes that were treated with ESWL sessions. Median age at first procedure was 9 years old (1-17) and median follow-up time was 6 years (3-12). Stones were located in the renal pelvis, followed by the lower, middle and upper calyx, proximal ureter, and 51% of our patients had multiple lithiasis. Median stone size was 12 mm (5-45), the main component being calcium oxalate (34%). During immediate postoperative period, 8 patients (19%) presented complications: renal colic, hematuria and urinary tract infection. After the first ESWL, 41% of the patients (n = 17) were stone-free. Out of the 24 residual lithiasis episodes (58%), three patients (7%) underwent a second ESWL session. In the remaining 19 patients, ESWL was combined with URS or percutaneous approach to achieve complete stone clearance. Overall stone free status after combined therapy was 95% (n = 39). Conclusion: These data support that ESWL is an effective minimally invasive technique, with low cost and morbidity, reproducible and safe for the treatment of stone disease in children. Even though lithiasis size seems to be a significant factor in ESWL success, in combination with other lithotripsy procedures it can reach very high rates of stone clearance.

Noncontrast computed tomography factors that predict the renal stone outcome after shock wave lithotripsy

OBJECTIVES

Extracorporeal shock wave lithotripsy (ESWL) is a popular treatment for nephrolithiasis. We took advantage of noncontrast abdominal computed tomography (NCCT) to search the possible prognostic factors including abdominal fat distribution influencing stone-free rate.

METHODS

From August 2008 to August 2010, 145 patients who had renal calculus and had undergone ESWL were retrospectively reviewed. All of them received NCCT assessment before ESWL and were followed up after 1 month for stone clearance. These patients were divided into two groups: one was the stone-free group and the other was the residual-stone group. Affecting parameters included stone size, location, stone surface area, Hounsfield unit density (HU density), skin-to-stone distance (SSD), and abdominal fat area as analyzed between these two groups.

RESULTS

Of 145 patients, 70 were stone-free and 75 had residual stone after ESWL treatment and 1-month follow-up. From univariate analysis, stone size, HU density, SSD, and stone surface area were significant predicting factors for ESWL success. On multivariate analysis, the important factors influencing ESWL outcomes were HU density and stone surface area (odds ratio 1.002 vs. 77.18, respectively; P<.05). Abdominal fat accumulation and distribution had no significant difference between these two groups.

CONCLUSION

This study revealed that stone size, HU density, SSD, and stone surface area were associated with stone-free rate after ESWL treatment. Therefore, these factors could be used to assess the feasibility of ESWL before deciding the treatment strategy. Abdominal fat distribution had no significant impact on ESWL outcome for renal stones.

The glue-clot technique: a new technique description for small calyceal stone fragments removal

During the last 20 years, the technology advancement of small flexible ureterorenoscopes has dramatically changed the management of renal calculi. Retrograde intrarenal surgery (RIRS) has currently a high impact on active stone treatment, and it is increasingly used worldwide. Nevertheless, kidney stone fragmentation and direct removal of fragments require many passages of the ureteroscope, is often time-consuming, and may be very difficult through anatomical and technical factors. We describe a simple, feasible and efficient technique for small stone fragments retrieval, which are often difficult to remove during RIRS.

Modified Seoul National University Renal Stone Complexity score for retrograde intrarenal surgery

The Seoul National University Renal Stone Complexity (S-ReSC) score is a well-validated tool for the prediction of stone-free rate (SFR) after percutaneous nephrolithotomy. We modified the S-ReSC score system for application to retrograde intrarenal surgery (RIRS) and evaluated this score. A total of 88 patients who underwent RIRS from 2011 to 2013 were included. The modified S-ReSC score was assigned according to the number of sites involved in the renal pelvis (#1), superior and inferior major calyceal groups (#2-3), and anterior and posterior minor calyceal groups of the superior (#4-5), middle (#6-7), and inferior calyx (#8-9). If the stone was in the inferior sites (#3, #8-9), one additional point per site was added to the original score. The SFR was examined according to the modified S-ReSC score. To evaluate the predictive accuracy, the area under the receiver operating characteristic curve (AUC) was used and compared with the Resorlu-Unsal Stone (RUS) score. The SFR was 85.2% and was significantly decreased in the order of low (1-2: 94.2%), medium (2-4: 84.0%), and high (>4: 45.5%) modified ReSC score groups (p < 0.001). AUCs of the modified S-ReSC score (0.806) and score group (0.766) were higher than the AUC of the RUS score (0.692; p = 0.012 and p = 0.040, respectively). The modified S-ReSC score predicts the SFR after RIRS well. Furthermore, its predictive accuracy is higher than that of the RUS score.

Extracorporeal shock wave lithotripsy: An opinion on its future

The development of miniaturized nephroscopes which allow one-stage stone clearance with minimal morbidity has brought the role of shock wave lithotripsy (SWL) in stone management into question. Design innovations in SWL machines over the last decade have attempted to address this problem. We reviewed the recent literature on SWL using a MEDLINE/PUBMED research. For commenting on the future of SWL, we took the subjective opinion of two senior urologists, one mid-level expert, and an upcoming junior fellow. There have been a number of recent changes in lithotripter design and techniques. This includes the use of multiple focus machines and improved coupling designs. Additional changes involve better localization real-time monitoring. The main goal of stone treatment today seems to be to get rid of the stone in one session rather than being treated multiple times non-invasively. Stone treatment in the future will be individualized by genetic screening of stone formers, using improved SWL devices for small stones only. However, there is still no consensus about the design of the ideal lithotripter. Innovative concepts such as emergency SWL for ureteric stones may be implemented in clinical routine.

Is tubeless percutaneous nephrolithotomy a feasible technique for the treatment of staghorn calculi?

Purpose

Tubeless percutaneous nephrolithotomy (PNL) remains a challenging technique for the surgical treatment of staghorn renal calculi. Our study was designed to compare surgical outcomes between conventional and tubeless PNL.

Materials and Methods

We retrospectively enrolled consecutive patients who underwent conventional or tubeless PNL under general anesthesia performed by a single surgeon (H.J.) for the treatment of staghorn calculi between 2003 and 2012. All patients were divided into two groups: group 1 included patients who underwent conventional PNL and group 2 included patients who were managed by tubeless PNL for the treatment of staghorn calculi. Preoperative and postoperative parameters were analyzed between the two groups, including age, stone burden, complications, any interventions, and duration of hospital stay.

Results

A total of 165 patients (group 1, 106; group 2, 59) were enrolled in the study. No significant differences in age, sex, body mass index, or stone laterality were observed between the two groups. The mean stone burdens (±standard deviation) of group 1 and group 2 were 633.6 (±667.4) and 529.9 (±362.8), respectively (p=0.271). The postoperative stone-free clearance rate was higher in group 2 (78.0%) than in group 1 (69.8%); however, the difference was not clinically significant (p=0.127). In addition, no significant differences in postoperative complications, including fever, bleeding, infection, or additional interventions, were observed between the two groups.

Conclusions

Our results demonstrated that tubeless PNL has the same effectiveness and safety as conventional PNL in the treatment of staghorn calculi. Tubeless PNL may be feasible for managing renal staghorn calculi.

Factors affecting the outcome of extracorporeal shock wave lithotripsy for unilateral urinary stones in children: a 17-year single-institute experience

PURPOSE

Extracorporeal shock wave lithotripsy (ESWL) is a first-line treatment for pediatric urinary stone disease. We aimed to determine the factors affecting the outcome of ESWL for unilateral urinary stones in children.

MATERIALS AND METHODS

A total of 81 pediatric patients aged 0 to 16 years with urinary stones treated by ESWL from January 1995 through May 2012 were retrospectively reviewed. All patients were required to have unilateral urinary stone disease. Children who underwent other surgical procedures before ESWL were excluded. Outcomes evaluated after ESWL were the stone-free rate at 3 months after ESWL, success within a single session, and success within three sessions. Factors affecting the success within three sessions were also analyzed.

RESULTS

The final analysis was for 42 boys and 22 girls (mean age, 9.2±5.2 years). Of these 64 patients, 58 (90.6%) were treated by ESWL without other surgical procedures and 54 (84.4%) were successfully treated within three ESWL sessions. In the multivariate analysis, multiplicity (odds ratio [OR], 0.080; 95% confidence interval [CI], 0.012 to 0.534; p=0.009) and large stone size (>10 mm; OR, 0.112; 95% CI, 0.018 to 0.707; p=0.020) were significant factors that decreased the success rate within three ESWL sessions.

CONCLUSIONS

Most of the pediatric urinary stone patients in our study (90.6%) were successfully treated by ESWL alone without additional procedures. If a child has a large urinary stone (>10 mm) or multiplicity, clinicians should consider that several ESWL sessions might be needed for successful stone fragmentation.

Comparison of percutaneous nephrolithotomy, shock wave lithotripsy, and retrograde intrarenal surgery for lower pole renal calculi 10-20 mm

OBJECTIVE

To compare the results of percutaneous nephrolithotomy (PCNL), shock wave lithotripsy (SWL), and retrograde intrarenal surgery (RIRS) for 1- to 2-cm lower pole kidney stones.

PATIENTS AND METHODS

This retrospective study was based on data collected from the files of patients between January 2007 and May 2012. The files of 383 patients (221 SWL, 144 PCNL, 38 RIRS) were evaluated. The groups were compared for stone size, success rate, and complication rate using the modified Clavien grading system.

RESULTS

The stone burdens of the groups were similar (p = 0.36). The success rates were 76, 94, and 73%, respectively, in SWL, PCNL, and RIRS. The highest stone-free rate was in the PNL group (p < 0.05). When the complication rates were evaluated using the Clavien grading system, they were determined to be 13% in PCNL, 3% in SWL, and 5% in RIRS. Especially GII and GIII complications were more common in the PCNL group (p < 0.05).

CONCLUSION

PCNL seems to be the most successful but most invasive method. However, with relatively low complication rates, SWL and RIRS are other techniques to keep in mind. To determine the first-line treatment, prospective randomized studies with larger series are needed.

[Urolithiasis in childhood]

Urinary stone disease is relatively rare in children with an overall incidence of 1-2 %; however, it is often associated with metabolic abnormalities that may lead to recurrent stone formation. Stone analysis and subsequent metabolic evaluation is therefore mandatory for this high-risk group after the first stone event. The objectives of stone management in children should be complete stone clearance, prevention of stone recurrence, preservation of renal function, control of urinary tract infections, correction of anatomical abnormalities and correction of the underlying metabolic disorders. The full range of minimally invasive procedures is available if active stone removal is necessary. The majority of stones in children can be managed either with extracorporeal shock wave lithotripsy which has a higher efficacy in children than in adults, percutaneous nephrolithotomy, ureterorenoscopy or a combination of these modalities while open or laparoscopic surgery is limited to well-selected cases with underlying anatomical abnormalities.

Comparison of extracorporeal shock wave lithotripsy for inferior caliceal calculus between children and adults: a retrospective analysis--why do results vary?

OBJECTIVE

To retrospectively evaluate the effectiveness of extracorporeal shock wave lithotripsy (ESWL) for inferior caliceal calculi ≤ 20 mm in size and compare the results between children and adults.

MATERIALS AND METHODS

From January 2004 to January 2012, ESWL was performed for inferior caliceal calculi in 230 children and 1006 adults. The Dornier compact alpha-K1025163 (Dornier Med Tech) was used. The success rates, number of ESWL sessions required, and auxiliary procedures used were evaluated in a comparative manner.

RESULTS

The overall stone-free rate (for both stone sizes) was 82.2% for children and 40% for the adults. Of the children, 17% had a residual stone compared with 47.8% of the adults. ESWL was unsuccessful in 0.8% of children and 12.2% of adults. The mean number of ESWL sessions required in children and adults was 1.43 (range 1-4) and 2.13 (range 1-4), respectively. Repeat treatment was required in 31% of the children and 65% of the adults. Auxiliary procedures were required in 5.2% of the children and 16.2% of the adults. Complications were seen in 5.6% of the children and 15% of the adults.

CONCLUSION

The results of ESWL for inferior caliceal calculi ≤ 20 mm in adults remains poor but not so in children. Children can achieve high stone-free rates, require a fewer number of ESWL sessions than adults to be stone free, and have a lower need for repeat treatment and auxiliary procedures, and have fewer complications.