Impact of colic pain as a significant factor for predicting the stone free rate of one-session shock wave lithotripsy for treating ureter stones: a Bayesian logistic regression model analysis

Effect of acupressure on pain intensity and physiological indices in patients undergoing extracorporeal shock wave lithotripsy: a randomized double-blind sham-controlled clinical trial

BACKGROUND

Despite the widespread use of extracorporeal shock wave lithotripsy (ESWL) as a treatment for kidney stones, it is essential to apply methods to control pain and improve patient comfort during this procedure. Therefore, this study aimed to investigate the effect of acupressure at the Qiu point on pain intensity and physiological indices in patients undergoing ESWL.

METHODS

This randomized, sham-controlled clinical trial was conducted at the Shahid Beheshti Educational-medical Center in Hamadan City (western Iran) from May to August 2023. Seventy-four eligible patients were split into intervention (n = 37) and sham (n = 37) groups. Ten minutes before lithotripsy, the intervention group received acupressure at the Qiu point, while the sham group received touch at a neutral point. The primary outcomes were pain intensity measured by the Visual Analog Scale (VAS) and physiological indices such as blood pressure and heart rate at baseline, 1, 10, 20, 30, 40, and 50 min after the intervention. The secondary outcomes included lithotripsy success and satisfaction with acupressure application.

RESULTS

The analysis of 70 patients showed no significant differences in the demographic and clinical information of the patients across the two groups before the study (P > 0.05). Generalized estimating equations revealed that the interaction effects of time and group in pain and heart rate were significant at 30 and 40 min (P < 0.05). The results of this analysis for systolic blood pressure revealed a significant interaction at 30 min (P = 0.035). However, no significant interaction effects were found for diastolic blood pressure changes (P > 0.05).

CONCLUSIONS

Acupressure at the Qiu point positively impacts pain in patients undergoing ESWL treatment and increases their satisfaction. However, these results for physiological indices require further studies. Thus, acupressure can be considered a simple, easy, and effective option for pain management in patients during this procedure.

TRIAL REGISTRATION

[ https://en.irct.ir/trial/69117 ], identifier [IRCT20190524043687N4].

Pure uric acid stone prediction model using the variant coefficient of stone density measured by thresholding 3D segmentation-based methods: A multicenter study

Urinary stones are common urological diseases with increasing prevalence and incidence worldwide. Among the various types of stones, uric acid stones can be dissolved by oral chemolysis without any surgical procedure. Therefore, our study demonstrates that variant coefficient of stone density measured by thresholding a three-dimensional segmentation-based method from noncontrast computed tomography images can be used to identify pure uric acid stones from non-pure uric acid stones. This study provides a preoperative pure uric acid stone prediction model that could reduce invasive procedural treatments. The pure uric acid stone prediction model may offer optimized clinical decision-making for patients with urinary stones.

BACKGROUND AND OBJECTIVES

While most urinary stones are managed with interventional therapy, uric acid (UA) stones can be dissolved by oral chemolysis without invasive procedures. This study aimed to develop and validate a pure UA (pUA) stone prediction model using a variant coefficient of stone density (VCSD) measured by thresholding a three-dimensional (3D) segmentation-based method.

METHODS

Patients with urolithiasis treated at Keimyung University Dongsan Hospital between January 2017 and December 2020 were divided into training and internal validation sets, and patients from Kyungpook National University Hospital between January 2017 and December 2018 were used as an external validation set. Each stone was segmented by a thresholding 3D segmentation-based method using an attenuation threshold of 130 Hounsfield units. VCSD was calculated as the stone heterogeneity index divided by the mean stone density.

RESULTS

A total of 1175 urinary stone cases in 1023 patients were enrolled in this study. Of these, 224 (19.1%) were pUA stone cases. Among the potential predictors, thresholding 3D segmentation-based VCSD, age, sex, radio-opacity, hypertension, diabetes, and urine pH were identified as independent pUA stone predictors, and VCSD was the most powerful indicator. The pUA stone prediction model showed good discrimination, yielding area under the receiver operating characteristic curve of 0.960 (95% confidence interval (CI): 0.940-0.979, P < 0.001), 0.931 (95% CI: 0.875-0.987, P < 0.001), and 0.938 (95% CI: 0.912-0.965, P < 0.001) in the training, internal validation, and external validation sets, respectively.

CONCLUSIONS

VCSD measured using 3D segmentation was a decisive independent predictive factor for pUA stones. Furthermore, the established prediction model with VCSD can serve as a noninvasive preoperative tool to identify pUA stones.

The First 100 Cases of Endoscopic Combined Intrarenal Surgery in Korea: Matched Cohort Analyses versus Shock-Wave Lithotripsy

PURPOSE

This study presents our initial experience with endoscopic combined intrarenal surgery (ECIRS) for large renal stones and compares the results of a propensity score-matched cohort of patients undergoing shock-wave lithotripsy (SWL).

MATERIALS AND METHODS

A total of 100 adults underwent ECIRS for renal stones between August 2017 and January 2019. For comparison, 2172 patients who underwent a first session of SWL between January 2005 and May 2018 were included in the SWL cohort. Propensity score matching was performed using maximal stone length (MSL), mean stone density (MSD), and stone heterogeneity index (SHI) scores. Stone-free rate (SFR) and success rate were compared between ECIRS and SWL.

RESULTS

In the ECIRS group, the mean MSL, mean MSD, and mean SHI were 28.7±15.2 mm, 1013.9±360.0 Hounsfield units (HU), 209.4±104.0 HU, respectively. The SFR was 70%, and the success rate was 82.0% in this group. Although the ECIRS group had larger, harder, and more homogeneous stones than the SWL group, ECIRS showed a higher SFR and success rate than SWL. After propensity-score matching, SFR and success rate remained higher with ECIRS than with SWL (both, p<0.001). In multivariate logistic regression, smaller stone size [odds ratio (OR): 0.947, 95% confidence interval (CI): 0.913-0.979, p=0.002] and lower Seoul National University Renal Stone Complexity score (OR: 0.759, 95% CI: 0.610-0.935, p=0.011) were independent predictors of successful ECIRS.

CONCLUSION

ECIRS showed a higher SFR and success rate than SWL for large renal stones. Smaller stone size and lower complexity of stones were associated with a higher likelihood of successful ECIRS.

Use of extracorporeal physical vibration lithecbole through greater sciatic foramen for treatment of distal ureteral calculi

Introduction To evaluate the efficacy and safety of preforming extracorporeal physical vibration lithecbole(EVPL)through greater sciatic foramen(GSF)for distal ureteral calculi(DUC) treatment. Materials and methods All patients with a diagnosis of DUC (6 - 10 mm in diameter) were enrolled in this study from October 2018 to May 2020. Patients were randomly divided into three groups receiving EPVL through GSF (Group A, n = 58), or abdominal (Group B, n = 60), or combined with oral use of tamsulosin at 0.4 mg daily (Group C, n = 63). Results There was no significant difference observed in terms of demographic characteristics or size of stones among the three groups (p >0.05). Compared with the group B and C, patients of the group A displayed a significantly higher score of comfort but with significantly decreased number of renal colic attacks or analgesics required (p < 0.01). The stone-free rate also significantly increased after one and two weeks of treatment (p < 0.01), despite such a significant difference among these groups vanished after four weeks of treatment. Conclusion Extracorporeal physical vibrational lithecbole in the prone position use the greater sciatic foramen as the path is the safe and effective approach to treat the distal ureter calculi.

Structure Types of Kidney Stones and Their Susceptibility to Shock Wave Fragmentation

Background:

The modern approach in the treatment of urolithiasis involves the use of non-invasive and minimally invasive techniques based on the stone fragmentation, among which shock wave lithotripsy (SWL) is considered as the first-line treatment for kidney stones < 2 cm and proximal ureter stones.

Objective:

To study the microstructure and mineral composition of kidney stones and to evaluate their influence on the stones’ susceptibility to fragmentation by shock waves.

Methods:

The microstructure and mineral composition of kidney stone samples obtained from shock wave lithotripsy in 87 patients were studied using crystal optical analysis and infrared spectroscopy. The volume fraction of amorphous and crystalline phases of the stone composition, the quantitative and qualitative composition of mineral components were assessed. The fragmentation features of stones with different microstructure were retrospectively analyzed based on the total number of shock waves required for complete stone fragmentation.

Results:

Three kidney stone structure types were identified: amorphous-crystalline structure stones predominantly including the amorphous phase (type A); amorphous-crystalline structure stones predominantly including the crystalline phase (type B); fully crystalline structure stones (type C). Significant positive correlation between the total number of shock waves required for complete stone fragmentation and the volume fraction of crystalline phase was found.

Conclusion:

The structure type of kidney stones is determined by the volume ratio between the amorphous and crystalline phases of their composition. The amorphous-crystalline structure stones with the predominant content of the amorphous phase are more sensitive to shock-wave exposure. The increase in the volume fraction of crystalline phase in the stone structure reduces the stone’s susceptibility to fragmentation by shock waves.

Non-surgical treatment of urinary stone

Some patients with urinary stones can be managed non-surgically through observation, medication, or extracorporeal shockwave lithotripsy (ESWL). Symptomatic urinary stones can initially be treated conservatively using analgesics and hydration. When uncontrolled pain or infection is present, immediate diversion via either percutaneous nephrostomy or ureteral stenting may be necessary. Medical expulsive therapy utilizing alpha-blocker may benefit a selected group of patients with stones larger than 5 mm. Oral or percutaneous chemolysis is a well-established non-invasive option with a reasonable success rate for patients with a certain component such as uric acid. When medical treatment is applied, its unintended side effects should be considered and routinely monitored. Extracorporeal shockwave lithotripsy is a highly effective and safe modality in treating urinary stones when adequately indicated. In addition to the size and location of the stone, information obtained from non-enhanced computed tomography such as stone density, stone heterogenicity index, and stone-to-skin distance can be applied to predict the possibility of ESWL failure. Modifications in shock wave delivery by altering shock rate and voltage can improve shock wave efficacy. Urinary stones can be managed effectively and safely using non-surgical approaches.

Predictors of Uric Acid Stones: Mean Stone Density, Stone Heterogeneity Index, and Variation Coefficient of Stone Density by Single-Energy Non-Contrast Computed Tomography and Urinary pH

We analyzed the capacities of pertinent parameters (determined by single-energy non-contrast computed tomography [NCCT]) and urinary pH to predict uric acid stones. We reviewed the medical records of 501 patients whose stones were removed surgically or passed spontaneously between December 2014 and April 2016. Qualifying participants (n = 420) were stratified by the nature of the stone (calcium oxalate, uric acid, or infectious). Based on NCCT, we determined maximal stone length (MSL), mean stone density (MSD), and stone heterogeneity index (SHI) using Hounsfield units (HU) and calculated the variant coefficient of stone density (VCSD = SHI/MSD × 100). Urinary pH was also ascertained. Mean patient age was 55.55 ± 15.46 years. MSD (448.59 ± 173.21 HU), SHI (100.81 ± 77.37 HU), and VCSD (22.58 ± 10.55) proved to be significantly lower in uric acid versus other types of stones, as did urinary pH (5.33 ± 0.56; all p < 0.001). Receiver operating characteristic (ROC) curves depicting predictability of uric acid stones yielded area under ROC curve (AUC) values for MSD, SHI, VCSD, and urinary pH of 0.806 (95% CI: 0.761⁻0.850), 0.893 (95% CI: 0.855⁻0.931), 0.782 (95% CI: 0.726⁻0.839), and 0.797 (95% CI: 0.749⁻0.846), respectively, with corresponding cutpoints of 572.3 HU, 140.4 HU, 25.79, and 6.0. Among these four parameters, SHI was verifiably (DeLong's test) the most effective predictor of uric acid stones (all p < 0.001). Compared with MSD, VCSD, and urinary pH, SHI may better predict uric acid stones, using a cutpoint of 140.4 HU.

[Result of treatment of urinary lithiasis for professional aptitude]

INTRODUCTION

Military people are inapt for presence of urinary stones. In this specific population, the treatment of stones is even more aggressive than for the general population without recommendation. The final decision about aptitude is the responsibility of the military doctor. Whereas, ureteroscopy has its place there and must done by any urologist.

METHODS

The purpose of this study was to estimate the results of treatments by ureteroscopy in this population. Success was defined by the complete absence of fragment visualized in the imaging of control operating comment and so the end of the inaptitude time.

RESULTS

Between 2009 and 2016, forty-two were treated for ureteral or renal calculi. The population comprises of 93% men, 35 years old on average. The stones were mainly multiple (more 2) and the medium size is 5mm; sixteen (42.9%) was at the left and eight (19%) was bilateral. In 78.8% (78) of the cases there was a stone in renal position whose 50% (39) still at the lower calyx. In total, 5% of the patients were stone-free in 2 sessions on average. The average deadline of inaptitude of the initial consultation in the resumption of work was of 6 months. In 4% of the cases there was a complication operating rank 4.

CONCLUSION

This study confirms the feasibility, the weak harmlessness of ureteroscopy and the lesser deadline of inaptitude. Every urologist can treat this specific population. The patient must be informed and accept the treatment because of excluding referential.

LEVEL OF EVIDENCE

4.

Stone heterogeneity index on single-energy noncontrast computed tomography can be a positive predictor of urinary stone composition

The aim of this study was to investigate the correlation between stone composition and single-energy noncontrast computed tomography (NCCT) parameters, including stone heterogeneity index (SHI) and mean stone density (MSD), in patients with urinary calculi. We retrospectively reviewed medical records of 255 patients who underwent operations or procedures for urinary stones or had spontaneous stone passage between December 2014 and October 2015. Among these, 214 patients with urinary calculi who underwent NCCT and stone composition analyses were included in the study. Maximal stone length (MSL), mean stone density (MSD), and stone heterogeneity index (SHI) were determined on pretreatment NCCT. The mean MSD (454.68±177.80 HU) and SHI (115.82±96.31 HU) of uric acid stones were lower than those of all other types. Based on post hoc tests, MSD was lower for uric acid stones than for the other types (vs. CaOx: P<0.001; vs. infection stones: P<0.001). SHI was lower for uric acid stones than for the other types (vs. CaOx: P<0.001; vs. infection stones: P<0.001) Receiver operating characteristic curves of uric acid stones for MSD and SHI demonstrated that SHI (cut-off value: 140.4 HU) was superior to MSD (cut-off value: 572.3 HU) in predicting uric acid stones (P<0.001).

The transgluteal approach to shockwave lithotripsy to treat distal ureter stones: a prospective, randomized, and multicenter study

PURPOSE

We compared the outcomes of SWL to treat distal ureter stones with regard to the conventional prone and supine positions using the transgluteal approach through the greater sciatic foramen.

METHODS

A prospective, randomized, single-blind, and multicenter study was conducted between October 2014 and July 2015. The inclusion criteria were radio-opaque distal ureter stones with a maximum diameter of 0.5-2 cm as measured on a CT scan. The included 160 patients were randomly assigned to two groups: the prone group (n = 80; treated in the conventional prone position) and the transgluteal group (n = 80; treated in the supine position using a transgluteal approach). In the latter group, the focused shock wave was transmitted through the greater sciatic foramen with the head positioned at a 40° angle to the vertical. "Stone-free" was defined as the complete clearance of stone fragments, assessed using a CT scan at 2 weeks after treatment. Overall satisfaction was self-reported using a 0-5 Likert scale.

RESULTS

The overall efficacy was 66.9%. The stone-free rate was significantly higher in the transgluteal group (72.6%) than in the prone group (54.7%; odds ratio 2.413, 95% CI 1.010-5.761, P = 0.023). No serious adverse events due to treatment were observed in either group. The satisfaction score of the transgluteal group was 4.21 ± 0.81, and 83.6% were willing to repeat the same procedure if necessary.

CONCLUSIONS

SWL using the transgluteal approach via a supine position through the greater sciatic foramen was more effective than via the conventional prone position. Furthermore, this approach provided a comparably safe and satisfactory procedure.

Predictive factors and treatment outcomes of Steinstrasse following shock wave lithotripsy for ureteral calculi: A Bayesian regression model analysis

Purpose

This study aims to assess the predictive factors and treatment outcomes of Steinstrasse formation following shock wave lithotripsy (SWL) for ureter stone.

Materials and Methods

The medical records of 1,418 ureter stone patients who underwent one-session SWL from November 2005 to May 2013 at our medical institute were retrospectively reviewed. Finally, 551 patients met inclusion criteria. Maximal length and location of stone, stone attenuation (Hounsfield units), and skin-to-stone distance (SSD) were determined on pretreatment non-contrast computed tomography.

Results

Of 551 patients, 12 patients (2.2% of total cohort) developed Steinstrasse after one-session SWL. The Steinstrasse incidence was significantly associated with stone size, stone attenuation value, and SSD. Prophylactic ureter stenting was not a statistically significant predictor of Steinstrasse formation. After propensity-score matching, Steinstrasse group showed a significant shorter SSD compare to non-Steinstrasse group. Multivariate logistic regression and Bayesian analysis revealed that stone size, stone attenuation and SSD were significant predictor of Steinstrasse formation following SWL for ureter stone. The Steinstrasse resolved spontaneously in six patients and remaining six patients were treated by additional SWL. None of patients with Steinstrasse required ureteral stenting, percutaneous drainage, or consequent surgical intervention.

Conclusions

Steinstrasse formation following SWL for ureter stone was rare event but nonnegligible. Large stone size, high stone attenuation and short SSD were significant predictors of Steinstrasse formation following SWL for ureter stone. Majority of patients with Steinstrasse formation could be treated conservatively in this clinical scenario.

Digital Videoscopic Retrograde Intrarenal Surgeries for Renal Stones: Time-to-Maximal Stone Length Ratio Analysis

PURPOSE

To investigate 100 consecutive cases of videoscopic retrograde intrarenal surgery (RIRS) by a single surgeon and to evaluate factors associated with stone-free status and the learning curve thereof.

MATERIALS AND METHODS

We analyzed the results of videoscopic RIRS in 100 patients who underwent primary treatment for renal stones from January 2015 to August 2016. Videoscopic RIRS were performed with URF-V and URF-V2 flexible video uteroscopes (Olympus) or a Flex-Xc flexible ureterorenoscope (KARL STORZ). Non-contrast computed tomography was taken at 3 months postoperatively to confirm the absence of stones. The stone characteristics included the location, maximal stone length (MSL), stone heterogeneity index (SHI), and mean stone density (MSD). Fragmentation efficacy was calculated as operative time (min) divided by removed MSL (mm), and was evaluated in the sequential order of operations.

RESULTS

The mean age of the total patient was 60.0±14.0 years. The mean MSL was 13.1±6.2 mm. The average MSD was 734.2±327.6 Hounsfield unit (HU) and the SHI was 241.0±120.0 HU. The mean operation time was 65.1±45.7 min considering each renal unit. The stone-free rate at 3 months post-surgery was 87%. The estimated cut-off of the time-to-MSL ratio below 5 min/mm was 50. Multivariate analyses indicated a lower MSD [odds ratio (OR): 0.998; 95% confidence interval (CI): 0.996-0.999; p=0.047) and the last 50 cases (OR: 5.408, 95% CI: 1.337-30.426; p=0.030) as independent predictors of stone-free status after videoscopic RIRS.

CONCLUSION

Low MSDs and the last 50 cases were significant predictors of stone-free rate in videoscopic RIRS.

Impact of Pretreatment Hydronephrosis on the Success Rate of Shock Wave Lithotripsy in Patients with Ureteral Stone

PURPOSE

To evaluate predictors of the success rate for one session of shock wave lithotripsy (SWL), focusing on the relationships between pretreatment hydronephrosis grade and one-session SWL success rates.

MATERIALS AND METHODS

The medical records of 1824 consecutive patients who underwent an initial session of SWL for treatment of urinary stones between 2005 and 2013 were reviewed. After exclusion, 700 patients with a single, 4-20 mm diameter radiopaque calculus were included in the study.

RESULTS

The mean maximal stone length (MSL) and skin-to-stone distance were 9.2±3.9 and 110.8±18.9 mm, respectively. The average values for mean stone density (MSD) and stone heterogeneity index (SHI) were 707.0±272.1 and 244.9±110.1, respectively. One-session success rates were 68.4, 75.0, 75.1, 54.0, and 10.5% in patients with hydronephrosis grade 0, 1, 2, 3, and 4, respectively. Patients were classified into success or failure groups based on SWL outcome. Multivariate logistic regression analyses revealed that MSL [odds ratio (OR) 0.888, 95% confidence intervals (CI): 0.841-0.934, p<0.001], MSD (OR 0.996, 95% CI: 0.995-0.997, p<0.001), SHI (OR 1.007, 95% CI: 1.005-1.010, p<0.001), and pretreatment hydronephrosis grade (OR 0.601, 95% CI: 0.368-0.988, p=0.043) were significantly associated with one-session success.

CONCLUSION

Pretreatment grades 3 or 4 hydronephrosis were associated with failure of SWL in patients with a single ureteral stone. In the presence of severe hydronephrosis, especially hydronephrosis grade 4; physicians should proceed cautiously in choosing and offering SWL as the primary treatment for ureteral stone.

Ureteral stenting can be a negative predictor for successful outcome following shock wave lithotripsy in patients with ureteral stones

Purpose

To evaluate ureteral stenting as a negative predictive factor influencing ureteral stone clearance and to estimate the probability of one-session success in shock wave lithotripsy (SWL) patients with a ureteral stone.

Materials and Methods

We retrospectively reviewed the medical records of 1,651 patients who underwent their first SWL. Among these patients, 680 had a ureteral stone measuring 4–20 mm and were thus eligible for our study. The 57 patients who underwent ureteral stenting during SWL were identified. Maximal stone length (MSL), mean stone density (MSD), skin-to-stone distance (SSD), and stone heterogeneity index (SHI) were determined by pre-SWL noncontrast computed tomography.

Results

After propensity score matching, 399 patients were extracted from the total patient cohort. There were no significant differences between stenting and stentless groups after matching, except for a higher one-session success rate in the stentless group (78.6% vs. 49.1%, p=0.026). In multivariate analysis, shorter MSL, lower MSD, higher SHI, and absence of a stent were positive predictors for one-session success in patients who underwent SWL. Using cutoff values of MSL and MSD obtained from receiver operator curve analysis, in patients with a lower MSD (≤784 HU), the success rate was lower in those with a stent (61.1%) than in those without (83.5%) (p=0.001). However, in patients with a higher MSL (>10 mm), the success rate was lower in those with a stent (23.6%) than in those without (52.2%) (p=0.002).

Conclusions

Ureteral stenting during SWL was a negative predictor of one-session success in patients with a ureteral stone.

Comparison of High, Intermediate, and Low Frequency Shock Wave Lithotripsy for Urinary Tract Stone Disease: Systematic Review and Network Meta-Analysis

OBJECTIVES

To perform a systematic review and network meta-analysis of randomized controlled trials (RCTs) to determine the optimal shock wave lithotripsy (SWL) frequency range for treating urinary stones, i.e., high-frequency (100-120 waves/minute), intermediate-frequency (80-90 waves/minute), and low-frequency (60-70 waves/minute) lithotripsy.

MATERIALS AND METHODS

Relevant RCTs were identified from electronic databases for meta-analysis of SWL success and complication rates. Using pairwise and network meta-analyses, comparisons were made by qualitative and quantitative syntheses. Outcome variables are provided as odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

Thirteen articles were included in the qualitative and quantitative synthesis using pairwise and network meta-analyses. On pairwise meta-analyses, comparable inter-study heterogeneity was observed for the success rate. On network meta-analyses, the success rates of low- (OR 2.2; 95% CI 1.5-2.6) and intermediate-frequency SWL (OR 2.5; 95% CI 1.3-4.6) were higher than high-frequency SWL. Forest plots from the network meta-analysis showed no significant differences in the success rate between low-frequency SWL versus intermediate-frequency SWL (OR 0.87; 95% CI 0.51-1.7). There were no differences in complication rate across different SWL frequency ranges. By rank-probability testing, intermediate-frequency SWL was ranked highest for success rate, followed by low-frequency and high-frequency SWL. Low-frequency SWL was also ranked highest for low complication rate, with high- and intermediate-frequency SWL ranked lower.

CONCLUSIONS

Intermediate- and low-frequency SWL have better treatment outcomes than high-frequency SWL when considering both efficacy and complication.