Extracorporeal Shock Wave Lithotripsy for Ureteral Stones: Do Decompression Tubes Matter?

Is extracorporeal lithotripsy a first-line treatment for urinary stones today?

OBJECTIVE

To evaluate the efficacy and complications of extracorporeal lithotripsy (SWL) as a first-line treatment for renal and ureteral stones METHODS: Retrospective and observational study of all the patients treated with lithotripsy in a third level center between January 2014 and January 2021; characteristics of the patients, the stones, complications and results of SWL is recollected. Multivariate logistic regression of the factors associated with stone size reduction was performed. A statistical analysis of the factors associated with additional treatment after SWL and factors associated with complications is also executed.

RESULTS

1727 patients are included. Stone mean size was 9,5mm. 1540 (89.4%) patients presented reduction in stone size. In multivariate analysis, stone size (OR=1.13; p=0.00), ureteral location of the lithiasis (OR=1.15; p=0.052) and number of waves (p=0.002; OR=1.00) used in SWL are the factors associated with reduction of stone size. Additional treatment after lithotripsy was needed in 665 patients (38.5%). The factors associated with the need for retreatment were stone size (OR=1.131; p=0.000), number of waves (OR=1.000; p=0.000), energy (OR=1.005; p=0.000). 153 patients (8.8%) suffered complications after SWL. A statistically significant association was found between the size of the lithiasis (p=0.024, OR=1.054) and the previous urinary diversion (P=0.004, OR=0.571).

CONCLUSION

Lithotripsy remains an effective treatment as the first line of therapy for reno-ureteral lithiasis with a low percentage of complications.

A novel model using computed tomography parameters to predict shock wave lithotripsy success in ureteral stones at different locations

OBJECTIVE

To combine non-contrast computerized tomography (NCCT)-based parameters with stone and patient characteristics that are already known to affect shock wave lithotripsy (SWL) success and assess this novel model's effectiveness in predicting SWL success for single ureteral stones in different locations.

MATERIALS AND METHODS

Data of patients treated by SWL for a single ureteral stone between January 2017 and January 2019 were retrospectively reviewed. Demographic parameters of patients and stone characteristics were combined with NCCT-based parameters. NCCT-based parameters included the presence or absence of hydronephrosis, perinephric stranding, periureteral edema, diameter of the proximal ureter, ureteral wall thickness (UWT) at ureteral stone site. The logistic regression method was used for the development of a useful predictive model. Subsequently, the receiver operating curve was used to determine cut-off levels, and a scoring system was developed for prediction of SWL success.

RESULTS

Stone-free rate was 77,1% (267/346) in the entire cohort. Univariate analysis revealed that age, stone volume, density, perinephric stranding, diameter of proximal ureter, and UWT, were associated with SWL success. In multivariate analysis, proximal ureteral stone location, stone volume, density, and UWT were independent predictors of SWL success. The formula used during logistic regression analysis was: 1/[1 + exp {-8.856 + 0.008 (stone volume) + 0.002 (stone density) + 0.673 (UWT) + 1026 (proximal ureteral stone)}]. The scores of 0, 1, 2, 3 and 4 were associated with 97,8%, 83,4%, 60,8%, 33,2% and 11,1% success rates, respectively, in the prediction model based on these parameters.

CONCLUSION

We conclude that our model can facilitate decision-making for SWL treatment of ureteral stones in different locations.

Immediate Shockwave Lithotripsy vs Delayed Shockwave Lithotripsy After Urgent Ureteral Stenting in Patients with Ureteral or Pyeloureteral Urolithiasis: A Matched-Pair Analysis

Introduction: The most common cause of acute renal colic is a ureteral obstruction caused by ureterolithiasis. Urgent intervention is often necessary due to intractable pain. Early extracorporeal shockwave lithotripsy (SWL) as an alternative treatment option to ureteral stenting becomes forgotten in times of rising ureterorenoscopy. However, definitive guidelines are lacking, in which urgent treatment should be preferred in the absence of signs of infection. Therefore, we assessed efficacy and safety of early SWL (eSWL) to secondary SWL (sSWL) after urgent ureteral stenting. Patients and Methods: One hundred four patients treated between January 2015 and November 2017 for obstructive ureterolithiasis were matched regarding stone size, stone localization, and assigned to group eSWL (n = 52) or group sSWL (n = 52). The eSWL group received shock waves (without prior ureteral stenting) and sSWL group ureteral stenting within 48 hours from diagnosis. Thereafter, patients in group sSWL were treated with shock waves for a median of 23 ± 14.6 days after ureteral stenting. Stone-free rates, complication rates, and reintervention rates were assessed. Univariable and multivariable logistic regression was applied to find predictors of outcomes in the two treatment groups. Results: Overall, there was no statistically significant difference between both groups regarding stone-free rate and complication rate. Reinterventions were more often addressed for patients in group sSWL (p = 0.05). eSWL was significantly superior to sSWL regarding stone-free rates for stones between 6 and 9 mm (p = 0.04). At the multivariable multinomial logistic regression none of the two treatment modalities was associated with better outcomes. A body mass index ≥30 was associated with a reduced 6-week stone-free status (p = 0.04), whereas stones ≥8 mm were associated with an increased need of reintervention (p = 0.04). Conclusion: eSWL seems to be an effective and safe emergency procedure compared with sSWL after urgent stenting within 6 weeks and should be considered as a treatment option in patients without absolute indications for immediate ureteral drainage. Clinical trial registration number: 2019-00155.

Double J stent reduces the efficacy of extracorporeal shock wave lithotripsy in the treatment of lumbar ureteral stones

Introduction

We evaluated the effect of the presence of a double J stent on the efficacy of extracorporeal shock wave lithotripsy (ESWL) in the treatment of lumbar ureteral stones.

Material and methods

Between January 2007 and February 2012, we performed a retrospective cohort study. Forty–four patients were treated by ESWL for lumbar ureteral stones and included into two groups for the analysis: group 1, non–stented (n = 27) and group 2, stented patients (n = 17). Treatment efficacy was evaluated by abdominal X–ray or CT–scan at 1 month. Stone–free patients and those with a residual stone ≤4 mm were considered to be cured.

Results

Mean stone size and density in groups 1 and 2 were 8.2mm/831HU, and 9.7 mm/986HU respectively. Both groups were comparable for age, BMI, stone size and density, number, and power of ESWL shots given. The success rates in groups 1 and 2 where 81.5% and 47.1%, respectively (p = 0.017). There was no difference between the groups for stones measuring 8 mm or less (p = 0.574). For stones >8 mm, the success rates were respectively 76% and 22.2% for groups 1 and 2 (p = 0.030). Logistic regression analysis revealed a higher failure rate when a double J stent was associated with a stone >8 mm (p = 0.033).

Conclusions

The presence of a double J stent affects the efficacy of ESWL in the treatment of lumbar ureteral stones. This effect is significant for stones >8 mm. Ureteroscopy should be considered as the first–line treatment in such patients.