Percutaneous nephrolithotomy versus shock wave lithotripsy for high-density moderate-sized renal stones: A prospective randomized study

Effect of core preventative screening on kidney stone surgical patterns

PURPOSE

In the surgical treatment of kidney stones, decreased access to healthcare has been shown to exacerbate stone burden, often requiring more invasive and extensive procedures. The objective of this study is to evaluate the effects of preventative health screening on kidney stone surgical treatment patterns.

METHODS

We performed a retrospective analysis of data from the Healthcare Cost and Utilization Project (HCUP) Florida state-wide dataset and the PLACES Local Data for Better Health dataset from the Centers of Disease Control and Prevention (CDC). ZIP Code Tabulation Areas (ZCTAs) identified from the PLACES data were merged with the HCUP dataset to create a single dataset of community-level stone outcomes and community health measures. We included adult patients 18 years or older who underwent at least one urologic stone procedure from 2016 to 2020.

RESULTS

128,038 patients from 885 communities were included in the study. Patients underwent an average of 1.42 surgeries (Median = 1.39, SD = 0.16). Increased core preventative screening was associated with increased surgical frequency (Estimate: 0.51, P < 0.001). The low core preventative screening group had a higher prevalence of PNL than SWL while the high core preventative screening group had a low PNL prevalence compared to SWL.

CONCLUSION

Increased core preventative screenings are associated with less invasive kidney stone surgeries, suggesting that preventative screenings detect stones at an earlier stage.

Predictors of stone-free rate after a single-session extracorporeal shockwave lithotripsy for a single kidney stone measuring 10 to 20 mm: A private center experience

Background

Despite the continuous update of guidelines for the management of kidney stones, the ability to predict a successful response to extracorporeal shockwave lithotripsy (SWL) remains a topic of research. This is due to the need to refine the decision making in the context of technological advancements and current pandemics. This study aimed to determine the predictors of stone-free rate (SFR) after single-session SWL in adult patients with a single kidney stone 10 to 20 mm in diameter.

Materials and methods

A retrospective review of the records of patients with a single kidney stone 10 to 20 mm in diameter was performed at a private SWL center from December 2019 to February 2021. Univariate and multivariate analyses were performed for stone- and patient-related factors, using the Student t and Mann-Whitney U tests for the quantitative variables and the Fisher exact and Pearson correlation tests for the qualitative variables.

Results

A total of 138 patients were eligible for this study, including 92 men and 46 women. The mean age was 38.6 ± 12.4 years, and the mean body mass index (BMI) was 25.9 ± 3.4 kg/m2. Four weeks after SWL, 120 patients (87%) were free of stones, and 18 (13%) needed further treatment. Univariate analyses showed that SFR was negatively correlated with increased BMI (p = 0.0001), maximum stone length (p = 0.0001), transverse diameter of the stone (p = 0.0001), number of shocks per session (p = 0.052), and Hounsfield unit (HU) (p = 0.0001). Multivariate analysis revealed that HU (p = 0.009), maximum stone length (p = 0.01), BMI (p = 0.000), and presence of double-J stent (p = 0.034) were independent risk factors for failure of single-session SWL in the treatment of kidney stones 10 to 20 mm in diameter. The estimated average cost per case was USD 450.5.

Conclusions

Increased HU, maximum stone length, BMI, and presence of double-J stents were independent risk factors for low SFR after single-session SWL for a kidney stone 10 to 20 mm in diameter. The cost of SWL remains an advantage in the private sector.

Shockwave Lithotripsy Complications According to Modified Clavien-Dindo Grading System. A Systematic Review and Meta-regression Analysis in a Sample of 115 Randomized Controlled Trials

CONTEXT

Shockwave lithotripsy (SWL) shows clear associated benefits for urolithiasis patients.

OBJECTIVE

To identify and classify SWL complications according to modified Clavien-Dindo grading system while assessing the effect of different patient characteristics, stone parameters, types of lithotripters, and lithotripsy techniques.

EVIDENCE ACQUISITION

Literature was reviewed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement.

EVIDENCE SYNTHESIS

We analyzed the results of 115 randomized trials including 17827 patients, of whom 16.06%, 2.07%, 2.23%, 1.32%, 0.85%, 0.16%, and 0% suffered from Clavien I, II, III, IIIa, IIIb, IV, and V complications, respectively. In total, 18.43% of patients suffered from Clavien I-II and 2.48% from Clavien III-IV complications. In studies with >100 treated patients, Clavien I, III, and IV complication rates and need for auxiliary procedure rates were lower than in studies with smaller sample size. Electrohydraulic lithotripters led to a higher rate of Clavien IIIb and IV complications than electromagnetic lithotripters. Clavien I-II complications were increased by 14.3% in patients with multiple and complicated stones. Hematuria was increased by 8.29% in patients who underwent intravenous urography preoperatively and had longer duration of SWL. Pain occurrence was increased by 14.79% in patients with more than one stone at the time of SWL and by 3.21% in those who were managed with a piezoelectric lithotripter.

CONCLUSIONS

SWL should not be considered an uneventful procedure, as in 2.5% of cases an intervention or Clavien III-V complication will be observed. Low-volume centers, treatment of multiple or complex stones, a long-lasting SWL session, and electrohydraulic lithotripters are associated with higher rates of complications.

PATIENT SUMMARY

We analyze the occurrence of shockwave lithotripsy (SWL) complications in 17000 patients. In centers with larger caseloads, complications were less common. The type of lithotripter is associated with complications. An increased number of treated stones, complex stones, and increased SWL duration were associated with a higher incidence of pain and hematuria.

Efficacy of extracorporeal shockwave lithotripsy, with modified position of the machine head in the treatment of lower calyceal stones in obese patients

Context:

Extracorporeal shock wave lithotripsy (ESWL) has inferior results in the lower calyceal stones, especially in obese patients.

Aims:

This study aimed at evaluating of the efficacy of extracorporeal shockwave lithotripsy, with modified position of the machine head in the treatment of single lower calyceal stones in obese patients.

Settings and Design:

This was a prospective study (phase IV trial).

Subjects and Methods:

We studied the anterior rotation of the shock wave machine head in obese patients for the treatment of lower calyx stones. From February 2015 to June 2019, 105 obese patients (body mass index [BMI] ≥35) having lower calyx stones (≤20 mm) underwent ESWL at our institute. The procedure was done in a supine position, and the head of the shock-wave machine was tilted anteriorly. ESWL was considered successful if the kidney was completely cleared of stones.

Statistical Analysis Used:

The statistical methods used were descriptive statistics, mean, standard deviation frequency analysis, Chi-square test, unpaired t-test test, and Pearson correlations (r).

Results:

The mean BMI of these patients was 39.71 ± 2.8 kg/m², the mean stone size was 17.4 ± 2.1 mm, the mean stone density was 767.1 ± 193.4 Hounsfield unit, and the mean of skin to stone distance (SSD) was 145.4 ± 4.5 mm. ESWL was successful in 86 (81.9%) patients; 13 patients (12.4%) showed complete success after the first session, while 37 (35.2%), 25 (23.8%), and 11 (10.5%) patients showed success after the second, third, and fourth sessions, respectively. ESWL failed in 19 (19.1%) cases. The success rate decreased significantly with higher stone density and SSD (P < 0.001), with negative correlations (r values) of −0.871 and −0.811, respectively.

Conclusions:

Anterior rotation of the head of the shock wave machine is a suitable option for the treatment of lower calyceal stones in obese patients.

Optimization of shockwave lithotripsy use for single medium sized hard renal stone with stone density ≥ 1000 HU. A prospective study

PURPOSE

To identify shock wave lithotripsy (SWL) success predictors in hard renal stones (average stone density ≥ 1000 HU).

MATERIALS

We prospectively evaluated patients who underwent SWL for hard renal stones between April 2018 and December 2020. Radiological parameters were identified, e.g., stone site, size, the average density in addition to stone core and shell mean density, and renal cortical thickness (RKT). SWL sessions were performed using Doli-S lithotripter till a maximum of 3-4 sessions with 2-4 weeks interval. Initial response to SWL included stone fragmentation and decreased stone size after the first SWL. Treatment success was considered if complete clearance of renal stones occurred or in case of clinically insignificant residual fragments ≤ 4 mm after 12 weeks follow up by NCCT.

RESULTS

Out of 1878 patients who underwent SWL, the study included 157 patients with hard renal stones. Treatment overall success was found in 92 patients (58.6%) where 69 patients (43.9%) had complete stone clearance. On multivariate analysis, stone shell density < 901 HU, maximum stone size < 1 cm, RKT > 1.95 cm and initial treatment response were associated with increased the success rate after SWL for hard renal stones (P = 0.0001, 0.009, < 0.0001 and < 0.0001, respectively).

CONCLUSION

In hard renal stones, treatment overall success was found in 58.6% where complete stone clearance was found in 43.9%. Stone outer shell fragility, lower stone size, increased RKT and initial response to SWL were associated with a higher success rate at 12-week follow-up.

Is Percutaneous Nephrolithotomy the Modality of Choice Versus Extracorporeal Shockwave Lithotripsy for a 20 to 30 mm Single Renal Pelvic Stone with ≤1000 Hounsfield Unit in Adults? A Prospective Randomized Comparative Study

Objectives: To compare the efficacy, complications, and costs of percutaneous nephrolithotomy (PNL) and extracorporeal shock wave lithotripsy (SWL) in the treatment of a 20 to 30 mm single renal pelvic stone with a density ≤1000 HU. Patients and Methods: Eighty patients were prospectively randomized to receive either PNL or SWL during May 2017 to April 2019. The relevant demographic and clinical characteristics were compared. Results: The mean age in the PNL and SWL groups was 43.25 ± 15.16 and 44.18 ± 12.08 years, respectively. The mean stone sizes were 25.2 ± 3.9 and 24.6 ± 2.3 mm, respectively. The stone-free rate (SFR) was significantly different after the primary procedures (92.5% vs 37.5%, respectively; p < 0.04), but it was comparable after 3 months (97.5% vs 90%, respectively; p = 0.723), with a higher rate of auxiliary procedures after SWL (p = 0.017). On multivariate analysis, stone density was the only significant variable for the SFR in the SWL group (p = 0.004). Complications occurred in 27.5% and 22.5% of cases, respectively (p = 0.796). The mean costs of SWL (650.23 ± 424.74 United States Dollars [US$]) were significantly lower than those of PNL (1137.65 ± 224.43 US$; p < 0.0001). Conclusions: The SFRs for PNL and SWL were not significantly different after 3 months in the treatment of a 20 to 30 mm single renal pelvic stone with ≤1000 HU, although PNL provided a significantly higher rate after its primary procedure. SWL was significantly less costly, but it mandated a significantly higher number of auxiliary procedures than PNL.