Is there significance of the choice of prone versus supine position in the treatment of proximal ureter stones with extracorporeal shock wave lithotripsy?

Comparative analysis of renal calculi treatment via different extracorporeal shock wave lithotripsy (ESWL) pathways

OBJECTIVE

To compare the efficacy and safety of Extracorporeal Shock Wave Lithotripsy (ESWL) for treating renal calculi under different shock wave pathways.

METHODS

This study involved a prospective analysis of clinical data obtained from 264 eligible patients with renal stones treated at the Urology Department of Shanxi Bethune Hospital between January 2021 and June 2023. Among these patients, 125 underwent ESWL via the dorsal shock wave pathway (Group A), while 139 patients underwent ESWL via the ipsilateral clavicular midline shock wave pathway (Group B). Preoperatively, all patients underwent non-contrast abdominal CT (NCCT) scans to assess stone count, diameter, CT values, and Skin-to-Stone Distance (SSD). Intraoperatively, ultrasonography was utilized to remeasure SSD and monitor stone fragmentation continuously. The ESWL procedure employed a standardized intermittent stepwise energy escalation technique until treatment completion. Various metrics, including intraoperative Visual Analog Scale (VAS) pain scores, number of shocks, total shock wave energy, stone-free rate (SFR) at 4 weeks post-operation, and postoperative complication rates, were recorded and subjected to statistical analysis.

RESULTS

There were no statistically significant differences between the two groups regarding gender, age, BMI, stone count, stone diameter, stone CT values, intraoperative VAS pain scores, and postoperative complication rates (P>0.05). Preoperative SSD was significantly higher in Group B than in Group A (P<0.05), but there were no significant differences in intraoperative SSD between the groups (P>0.05). Group B showed significantly lower total shock wave energy and number of shocks compared to Group A (P<0.05). The stone-free rate (SFR) after 4 weeks did not exhibit significant differences between the groups (P>0.05). However, when the stone diameter was ≥1.3 cm, the SFR at 4 weeks post-operation in Group B was significantly higher than in Group A (P<0.05).

CONCLUSION

ESWL emerges as a safe and efficacious approach for treating renal calculi. Our findings suggest that utilizing the ipsilateral clavicular midline shock wave pathway in ESWL necessitates less shock wave energy and enhances efficiency, particularly in cases with larger stone burdens.

Efficacy of supine trans-abdominal pronated shock head ESWL for treatment of distal ureteric stones: A pilot study

OBJECTIVE

To evaluate the efficacy of extracorporeal shockwave lithotripsy (ESWL) in supine trans-abdominal approach for distal ureteric calculi and to determine the variables that could affect the outcome results.

MATERIALS AND METHODS

Between November 2019 and January 2021, 172 patients with a solitary distal ureteric calculus were treated with ESWL in supine position with a pronated shock wave head against the anterior abdominal wall. The outcome of treatment evaluated and the clinical and radiological findings, as well as stone characteristics, were reviewed and correlated with the stone-free rate (SFR).

RESULTS

Overall SFR was 84.84% (140/165). Those with stone clearance, 83.57% (117/140) cleared after one session and 16.42% (23/140) needed more than one session. Only three factors had a significant impact on SFR, that is stone length, stone width, stone attenuation. For stone length ⩽ 9 mm SFR was 93.44% (114/122) compared to 60.46% (26/43) for stone length of 10-12 mm (p < 0.00001). There were statistically significant increased SFR for stones with attenuation of <0.0001 and for the mean stone width of 8.02 mm (p < 0.00001). Stone localisation was easy with good patient comfort.

CONCLUSION

Supine trans-abdominal ESWL is a new, effective and safe form of treatment for distal ureteric calculi. The stone length, stone width along with stone attenuation were the only significant predictors of stone free status in supine position.

Transgluteal versus prone approach to extracorporeal shockwave lithotripsy for patients with distal ureteral stones: A systematic review and meta-analysis

To explore the effectiveness of transgluteal approach during extracorporeal shockwave lithotripsy (ESWL) for patients with distal ureteral stones compared to the prone approach. A systematic literature search was carried out by two reviewers independently on the basis of three electronic databases up to Aug. 2020. Three randomized controlled trials (RCT) and one cohort studies (CS), with a total of 516 patients, comparing transgluteal approach with prone approach during ESWL for distal ureteral stones were included. The methodological quality of RCT was evaluated by Cochrane collaboration's tools, and the quality of CS and CCS was evaluated by modified Newcatle-Ottawa scale. The weighted mean difference (WMD) and odds ratio (OR) was respectively used to describe results of continuous and dichotomous variables. Pooled data showed that transgluteal approach could significantly improve the rate of stone free after the first treatment [OR = 3.18, 95% confidence interval (CI) 2.19-4.63, p < 0.00001] and the rate of overall stone free (OR = 4.03, 95% CI 2.43-6.69, p < 0.00001). In addition, compared with the prone approach, the transgluteal one could also significantly reduce the rate of ureteroscopy (OR = 0.21, 95% CI 0.12-0.36, p < 0.00001). What's more, complications were rarely reported, which demonstrated a similar safety for two approaches. Our study suggested that, during ESWL for patients with distal ureteral stones, transgluteal approach was a safe and more effective choice than the prone position.

Extracorporeal shock wave lithotripsy for distal ureteric stones: which is the ideal approach?

OBJECTIVE

To compare the safety and efficacy of different approaches using ESWL for management of distal ureteric stone in an attempt to select the ideal one.

PATIENTS AND METHODS

This is a prospective randomized single-center study conducted on patients with lower third single radiopaque ureteric stone with size less than 15 mm. Patients were randomized into three groups, group A: Supine transgluteal, group B: Modified prone and group C: Prone position (80 patients each). The success of the procedure was assessed by NCCT and is defined as complete stone removal or had only clinically insignificant fragments (< 3 mm) for a maximum of three sessions. The success rate, rate of complications, pain intensity by visual pain scale and patients' satisfaction rate were compared among the three study groups.

RESULTS

Data of 240 patients were analyzed (80 in each group). Overall, no significant difference has been observed among all groups regarding demographic data, stone and treatment characteristics. The overall success rates for treatment after the last session were 86.3%, 65% and 62.5% in the three study groups, respectively, with a statistically significant difference for group A. Regarding pain perception and complication rate, all groups were comparable. Patient satisfaction is significantly better in group A versus the other two groups.

CONCLUSION

Our study has confirmed better efficacy profile and patients' satisfaction rate of ESWL in the supine position (transgluteal approach) than other different known approaches for the treatment of distal ureteral stones.

Anterior or posterior SWL in proximal ureteral stones opposite to 4th and 5th lumbar vertebrae?

BACKGROUND

Results of SWL in treatment of upper ureteral calculi are conflicting which is definitely affected by stone locations along the proximal ureter, which is may be due to the more deep and medial course of the ureter distally over the thick and strong abdominal back wall which may hinder shock waves.

METHODOLOGY

One hundred patients with radiopaque proximal ureteral stone opposite 4th and 5th lumbar vertebrae who had SWL were randomized into two groups. First group had SWL through anterior belly wall in supine position with countertraction, the second group had standard posterior SWL. Patient's demographics and stone characters were evaluated assessing stone burden and calculating S.T.O.N.E score. Patients were followed up to assess stone-free rate using serial digital plain X-ray KUB.

RESULTS

Anterior approach needed less power to reach SFR (p = 0.05) in less number of sessions where 90% of cases in anterior group had only one session to reach SFR versus 52% in posterior group (p = 0.001). Also, post-SWL pain, hematuria, obstruction and infection were significantly less in anterior group (p = 0.005). Although patients who had anterior approach showed statistically significant shorter time to stone expulsion. SFR does not differed significantly between study groups (p = 0.02). On further analysis; anterior SWL had a better chance to reach SFR (HR = 1.6, p = 0.001).

CONCLUSION

It seems that anterior SWL approach in supine position is safe and effective especially in mild obese patient with floppy abdomen. Patients who had anterior SWL approach had a better chance to achieve stone-free rate.

The alternating bidirectional versus the standard approach during shock wave lithotripsy for upper lumbar ureteric stones: a randomized controlled trial

PURPOSE

To compare the outcome of shock wave lithotripsy (SWL) for upper lumbar ureteric stones using the alternating bidirectional approach versus the standard approach during the first session.

METHODS

Our study was a randomized controlled trial including patients with single radio-opaque stone < 1 cm located in the upper lumbar ureter (from the ureteropelvic junction till the level medial to the lower margin of the kidney). SWL was conducted using electromagnetic Dornier Gemini Lithotripter. In group 1, patients were treated with the alternating under and over-table approach during the first session only and if other sessions were needed, the standard under-table approach was used. In group 2, patients were treated with the standard under-table approach during all sessions. Stone disintegration after the first session was assessed by kidney-ureter-bladder X-ray, renal ultrasonography and noncontrast computed tomography. Moreover, the incidence and severity of postoperative complications were evaluated.

RESULTS

Forty-eight patients in each group completed the study. Patient demographics and stone characteristics were comparable in both groups. Complete disintegration was achieved in 41.7% of patients in group 1 versus 18.8% in group 2 (P = 0.021). Stone-free rate (SFR) was 58.3% and 20.8% in group 1 and 2 respectively (P = 0.001). The mean session time was 56.42 min in group 1 versus 46.35 min in group 2 (P < 0.001). There was no significant difference in postoperative complications.

CONCLUSION

Stone disintegration and SFR after the first SWL session are higher when using the alternating bidirectional approach for upper lumbar ureteric stones at the expense of longer procedural duration.

TRIAL REGISTRATION

ClinicalTrials identifier (ID: NCT03243682), clinicaltrials.gov.

Assessing the Magnitude of Effect of Bone Structures on Shockwave Lithotripsy Fragmentation: Results from an In Vitro Study

INTRODUCTION

Several anatomic and clinical factors have been implicated in the failure rates of shock wave lithotripsy (SWL), including the attenuating effects of bony structures. We designed an in vitro model that incorporates the lumbar spine, including vertebral bodies and transverse processes along the pathway of shockwaves, to mimic the clinical scenario during SWL of upper ureteral stones. We hypothesized that the presence of bone structures in the SWL pathway significantly affects the fragmentation rate.

MATERIALS AND METHODS

An ordnance gelatin (OG) model was conceptualized and created to allow a pig's lumbar spine to be embedded within it. Artificial urinary calculi weighing 2 ± 0.1 g (1.2-cm diameter) were prepared using BegoStone plaster. The trial was divided into two arms: group 1 models had OG only and served as the control and group 2 models had the bone embedded in the gelatin with stone wells placed above the transverse processes. Twenty-four stones per group were subjected to SWL using the STORZ MODULITH SLX-F2 lithotripter, using the same treatment parameters. Fragments were sieved through 2- and 4-mm filters, and the fragmentation coefficients (FC) were calculated. The Mann-Whitney test was used to compare FC between the two groups.

RESULTS

The mean fragmentation rate of group 1 was statistically significantly higher compared with group 2 using a 4-mm sieve (43% vs 0.62%, p < 0.001) and the 2-mm filter (18% vs 0.52%, p < 0.001).

CONCLUSIONS

The presence of bone structures dramatically reduces the fragmentation rate of phantom stones using an OG in vitro model. The OG model is inexpensive and simple to use to simulate clinical situations during SWL.

Supine versus Prone Position during Extracorporeal Shockwave Lithotripsy for Treating Distal Ureteral Calculi: A Systematic Review and Meta-Analysis

PURPOSE

We aimed at evaluating the efficacy of extracorporeal shockwave lithotripsy (SWL) for treating distal ureteral calculi performed in supine vs. prone position.

MATERIALS AND METHODS

Eligible studies were identified by 2 reviewers using PubMed, Embase, and Web of Science databases. Outcomes included stone-free rate after the first and the final SWL session, the mean number of shocks per SWL session, the mean percentage of power used in the first SWL session, and the mean number of SWL sessions per patient.

RESULTS

Pooled data among the 647 included patients showed that supine SWL was associated with a significantly higher stone-free rate than prone SWL. This difference was consistent for both the first SWL session (OR 4.17; 95% CI 2.53-6.87; p < 0.00001) and the final session (OR 3.02; 95% CI 1.96-4.67; p < 0.00001). No differences in the mean number of shocks per SWL session, the mean percentage of power used in the first SWL session, and the mean number of SWL sessions per patient were observed between the positions. SWL complications were infrequent and the incidence was insufficient for further analysis.

CONCLUSION

SWL is safe and effective for the management of distal ureteral calculi, and supine SWL is more effective than prone SWL for achieving a stone-free status.

Percussion, diuresis, and inversion therapy for the passage of lower pole kidney stones following shock wave lithotripsy

BACKGROUND

Lower pole kidney stones typically have poor rates of spontaneous clearance from the body. Some studies have suggested that diuresis, percussion and inversion therapy could be beneficial for people with lower pole kidney stones following shock wave lithotripsy. There is however controversy about the relative benefits, harms, and efficacy of these interventions for the management of lower pole kidney stones.

OBJECTIVES

To identify the benefits and harms of percussion, diuresis, and inversion therapy to facilitate the passage of lower pole kidney stones following shock wave lithotripsy.

SEARCH METHODS

We searched the Cochrane Renal Group's specialised register up to 27 November 2013 through contact with the Trials' Search Co-ordinator using search terms relevant to this review.

SELECTION CRITERIA

All randomised controlled trials (RCTs) and quasi-RCTs looking at the benefits and harms of percussion, diuresis, and inversion therapy for aiding passage of lower pole kidney stones following shock wave lithotripsy were sought for assessment. The first phases of randomised cross-over studies were also eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study quality and extracted data. Results were expressed as relative risk (RR) for dichotomous outcomes and mean difference (MD) or standardised mean difference (SMD) for continuous data with 95% confidence intervals (CI).

MAIN RESULTS

We identified two small studies (177 participants) for inclusion and analysis. One study (69 participants) compared percussion, diuresis and inversion therapy following shock wave lithotripsy versus observation-only after shock wave lithotripsy. This study reported significantly higher stone-free rates in the intervention group (RR 0.62, 95% CI 0.47 to 0.82) and a significant reduction in stone burden (MD -3.30, 95% CI -3.58 to -3.03) compared to the observation-only group. They reported no significant differences in complication rates (RR 3.00, 95% CI 0.12 to 76.24).The second study (108 participants) compared percussion, diuresis, and inversion therapy plus shock wave lithotripsy with shock wave lithotripsy therapy alone. This study reported significantly higher stone-free rates in the intervention group (RR 0.36, 95% CI 0.17 to 0.80) and a significant reduction in stone burden (MD -0.30, 95% CI -0.04 to -0.56) compared to the control group. They reported no significant differences in complication rates (RR 2.54, 95% CI 0.10 to 63.72).For both studies selection bias was unclear; there was high risk of bias for performance bias; and detection, attrition and reporting bias were low.

AUTHORS' CONCLUSIONS

Limited evidence from two small studies indicated that percussion, diuresis, and inversion therapy may be safe and effective therapies to assist clearance of lower pole kidney stone fragments following shock wave lithotripsy. Methodological quality in both studies was assessed as moderate. Further well-designed and adequately powered studies are required to inform clinical practice.

Shock wave lithotripsy for distal ureteric stones: supine or prone

Shock wave lithotripsy (SWL) has become the preferred first-line approach to most patients with symptomatic urolithiasis. The purpose of this study is to assess the ideal patient position during SWL for the treatment of distal ureter stones. A total of 342 patients included in this retrospective study. 148 (108 men, 40 women) patients were included in the first group and were treated in supine position. The remaining 194 (143 men, 51 women) patients were included to second group and were treated in prone position. This study designed retrospectively. The procedure was accepted as a success if the patient was stone free or had only clinically insignificant fragments (≤3 mm) for 3 months or more after the last SWL session. Before SWL, the mean is one area in the first group was 61.32 mm2 while the mean stone area in the second group was 59.04 mm2 (p = 0.208). Mean energy, Mean energy maximum and mean number of applied shock waves of the first group was 4.65, 3.19 and 3,960, respectively. The same parameters in second group were 4.26, 3.03 and 2,953, respectively. These results show that there are statistically significant differences between two groups with respect to mean energy, mean energy maximum and mean number of applied shock waves (p = 0.003, p = 0.010, p = 0.000, respectively). Success rate was 85.1% in group 1 and 72.7% in group 2 (p = 0.006). Our results suggest that supine position is effective and better than prone position for SWL in patients with distal ureteric stones.

Ischemic cecal perforation secondary to ESWL of junctional stone in ureterosigmoidostomy (Mainz Pouch II)

We report an unusual case of ischemic cecal perforation after extracorporeal shock wave lithotripsy for an impacted stone at the distal end of the right ureter of a ureterosigmoidostomy in a 78-year-old female patient.

Optimizing Shock Wave Lithotripsy in the 21st Century

OBJECTIVE

Shock wave lithotripsy (SWL) has radically changed treatment of stone disease and appears to be the first option for the majority of patients. This review of current literature focused on suggestions for optimising technique, patient selection, results, and lithotriptor comparison for SWL.

METHODS

Literature search for SWL was performed for recently published papers in English language. Topics of interest were treatment protocols; patient evaluation; pre-SWL prediction of outcome; lithotriptor technology; efficacy; and methods to assess the effects, decrease complications, and compare lithotriptors. Earlier classic papers on SWL and guidelines for stone disease were also reviewed.

RESULTS

Recent literature contained important recommendations about SWL concerning (1) methods to predict stone fragmentation; (2) identification of factors contributing to treatment failure for lower pole and ureteric calculi; (3) guidelines from urological associations; (4) manoeuvres and changes in SWL delivery (slower rate, twin-pulse technique) to increase efficacy and decrease complications; (5) clarification of the role of medical treatment (antibiotics, alpha-blockers); (6) role of SWL in calyceal stones, CIRF, and abnormal kidneys; (7) obesity and SWL; and (8) methods to evaluate and compare lithotriptors.

CONCLUSIONS

SWL delivered in an outpatient setting as an anaesthesia-free treatment is still considered the first option for the majority of stones with a minimal number of complications. Better understanding of the physics of shockwave delivery is required, together with treatment optimisation by limiting renal damage and better selection of patients because this approach will offer maximum benefit to patients and physicians, as well as more cost-effective treatment.

Efficacy of Extracorporeal Shockwave Lithotripsy with Patients Rotated Supine or Rotated Prone for Treating Ureteral Stones: A Case-Control Study

PURPOSE

To improve the therapeutic efficacy of extracorporeal shockwave lithotripsy (SWL) for ureteral stones by attempting semilateral/rotated approaches. There has been no study that shows the advantage of rotated positions.

PATIENTS AND METHODS

Two hundred forty-eight (group 1) and 156 (group 1R) patients with proximal-ureteral stones were treated by the Dornier Lithotriptor U15/50 in the supine and rotated-supine position, respectively. When residual calculi remained in the middle-distal ureter, group 1 subjects underwent subsequent sessions in the ordinary prone position, and Group 1R patients were treated in the rotated-prone position. Sixty-two (group 2) and 60 (group 2R) patients with primary middle-ureteral stones were treated in the prone and rotated- prone position, respectively, while 110 (group 3) and 98 (group 3R) patients with distal-ureteral stones were treated in the prone and rotated-prone position, respectively.

RESULTS

Although the stone-free rate was not different in group 1 (94.8%) and 1R (97.4%), the number of sessions required for Group 1R patients to be stonefree (mean 1.49) was less than for Group 1 patients (mean 1.74; p=0.023). Group 1R patients tolerated a higher shockwave intensity than group 1 patients for sessions in the proximal ureter (p=0.042). The stone-free rate for Groups 1 and 1R for booster sessions in the middle- distal ureter was 85.4% and 100%, respectively (p=0.059). The stone-free rate for groups 2R (95.0%) and 3R (98.0%) was higher than that for groups 2 (83.9%) and 3 (89.1%) (p=0.046; p=0.011).

CONCLUSION

These effortless modifications bring about a superior outcome when treating ureteral calculi with SWL.