Relation of spontaneous passage of ureteral calculi to size

Enhancing sizing accuracy in ultrasound images with an alternative ADMIRE model and dynamic range considerations

Ultrasound imaging can struggle with sizing accuracy, especially when the targets have a significantly different amplitude compared to the surrounding background. In this work, we consider the challenging task of accurately sizing hyperechoic structures, and specifically kidney stones, where accurate sizing is critical for determining medical intervention. AD-Ex, an extended alternative model of our aperture domain model image reconstruction (ADMIRE) pre-processing method, is introduced and is designed to improve clutter removal and improve sizing accuracy. We compare this method against other resolution enhancing methods such as minimum variance (MV) and generalized coherence factor (GCF), and against those methods using AD-Ex as a pre-processing tool. These methods are evaluated among patients with kidney stone disease, with the task of accurately sizing the stones against the gold standard, computed tomography (CT). Stone ROI's were selected using contour maps as reference from which the lateral stone size was estimated. Among the in vivo kidney stone cases we processed, AD-Ex+MV had the overall lowest sizing error among the methods, with an average error of 10.8% compared to the next best method AD-Ex which had an average error of 23.4%. For reference, DAS had an average error of 82.4%. Though dynamic range was evaluated to determine optimal thresholding for sizing applications, variability between stone cases was too high for any conclusions to be drawn at this time.

Spontaneous stone expulsion in patients with history of urolithiasis

Objectives:

To examine differences in the presentation, management, and outcomes of patients admitted to the emergency department (ED) with ureteral stones, with prior history of urolithiasis compared to patients with a first stone event.

Patients and Methods:

Retrospective analysis of patients who visited the ED that were found to have a ureteral stone on CT. Patients were stratified into two groups: without history of urolithiasis (Group 1) and with history of urolithiasis (Group 2).

Results:

Between 2018 and 2020, 778 patients were admitted with ureteral stones. Patients in group 1 presented with a higher mean serum creatinine ( p = 0.02), larger mean stone size ( p < 0.0001), and a higher proportion of proximal ureteral stones ( p < 0.0001) than patients in group 2. The 30 day readmission rate was significantly higher in group 1 ( p = 0.02). Spontaneous stone expulsion was higher in group 2 ( p < 0.0001), whereas the need for endourological procedures was higher in group 1 ( p < 0.0001). On multivariable analysis serum creatinine (OR 0.264, 95% CI 0.091–0.769, p = 0.01) and stone size (OR 0.623, 95% CI 0.503–0.771, p < 0.0001) were associated with a lower spontaneous stone expulsion rate. History of prior endourological procedures (OR 0.225, OR 0.066–0.765, p = 0.01) was associated with a higher spontaneous stone expulsion rate.

Conclusions:

Our data suggests that patients who are first time stone formers present with larger and more proximal ureteral stones, with a lower likelihood of spontaneous stone expulsion and a subsequent need for surgical intervention. Previous stone surgery and not previous stone expulsion was found to be a predictor for spontaneous stone passage.

Imaging in stone diagnosis and surgical planning

PURPOSE OF REVIEW

Radiological imaging techniques and applications are constantly advancing. This review will examine modern imaging techniques in the diagnosis of urolithiasis and applications for surgical planning.

RECENT FINDINGS

The diagnosis of urolithiasis may be done via plain film X-ray, ultrasound (US), or contrast tomography (CT) scan. US should be applied in the workup of flank pain in emergency rooms and may reduce unnecessary radiation exposure. Low dose and ultra-low-dose CT remain the diagnostic standard for most populations but remain underutilized. Single and dual-energy CT provide three-dimensional imaging that can predict stone-specific parameters that help clinicians predict stone passage likelihood, identify ideal management techniques, and possibly reduce complications. Machine learning has been increasingly applied to 3-D imaging to support clinicians in these prognostications and treatment selection.

SUMMARY

The diagnosis and management of urolithiasis are increasingly personalized. Patient and stone characteristics will support clinicians in treatment decision, surgical planning, and counseling.

Development of prediction models of spontaneous ureteral stone passage through machine learning: Comparison with conventional statistical analysis

Objectives

To develop a prediction model of spontaneous ureteral stone passage (SSP) using machine learning and logistic regression and compare the performance of the two models. Indications for management of ureteral stones are unclear, and the clinician determines whether to wait for SSP or perform active treatment, especially in well-controlled patients, to avoid unwanted complications. Therefore, suggesting the possibility of SSP would help make a clinical decision regarding ureteral stones.

Methods

Patients diagnosed with unilateral ureteral stones at our emergency department between August 2014 and September 2018 were included and underwent non-contrast-enhanced computed tomography 4 weeks from the first stone episode. Predictors of SSP were applied to build and validate the prediction model using multilayer perceptron (MLP) with the Keras framework.

Results

Of 833 patients, SSP was observed in 606 (72.7%). SSP rates were 68.2% and 75.6% for stone sizes 5–10 mm and <5 mm, respectively. Stone opacity, location, and whether it was the first ureteral stone episode were significant predictors of SSP. Areas under the curve (AUCs) for receiver operating characteristic (ROC) curves for MLP, and logistic regression were 0.859 and 0.847, respectively, for stones <5 mm, and 0.881 and 0.817, respectively, for 5–10 mm stones.

Conclusion

SSP prediction models were developed in patients with well-controlled unilateral ureteral stones; the performance of the models was good, especially in identifying SSP for 5–10-mm ureteral stones without definite treatment guidelines. To further improve the performance of these models, future studies should focus on using machine learning techniques in image analysis.

Predictive factors of postoperative septic complications after flexible ureteroscopy for urinary stones

BACKGROUND

Flexible ureteroscopy (fURS) is one of the recommended treatments for urinary stones. Urosepsis is one of the most frequent complications of fURS however its predictive factors remain uncertain. Our objective was to assess the septic complications rates of fURS and to determinate predictive factors of these complications in patients undergoing fURS.

METHODS

Our retrospective analysis included all patients admitted for any fURS for stone disease in our center from December 2009 to April 2013. Patients' medical history, urine culture, stone composition, surgical and anesthetic characteristics were collected. The primary endpoint was defined by the presence of any septic complication (i.e. postoperative fever, urosepsis, septic shock or death). We used multivariate logistic regression to assess predictive factors of septic complication related to fURS.

RESULTS

Two hundred and eighty-two patients were included in this study. Urosepsis rate was 9.8% while 18.9% developed postoperative hyperthermia (>37.5°C). In multivariate analysis, the predictive risk factors of septic complication were: a neurologic disorder (OR=6.1; CI95%: 2.9-17.1), a history of urinary tract infection (UTI) (OR=19.6; CI95%: 7.3-52.1), exposure to peroperative nitrous oxide (OR=3.2; CI95%: 1.5-6.8) and intraoperative use of a laser (OR=8.0; CI95%: 13.0-30.3).

CONCLUSION

The use of fURS is associated with relatively frequent septic complications. Patients with neurologic disorders or a history of UTI carry an increased risk of postoperative complications. Limitations should be drawn with the use of peroperative nitrous oxide. These results should be further validated.

LEVEL OF EVIDENCE

3. Retrospective cohort study.

Efficacy of silodosin on the outcome of semi-rigid ureteroscopy for the management of large distal ureteric stones: blinded randomised trial

Objective

To evaluate the efficacy of silodosin therapy, as a new α-adrenergic receptor (α-AR) blocker, on the success rate of semi-rigid ureteroscopy (URS) for the management of large distal ureteric stones.

Patients and methods

This prospective study recruited 127 adult patients with single distal ureteric stone of ≥1 cm. The patients were randomly allocated to two groups: the first group included 62 patients who received silodosin (8 mg) for 10 days before URS (Silodosin group), whilst the second group included 65 patients who received placebo, in the form of multivitamins, for 10 days before URS (Placebo group). All patients underwent URS and a pneumatic lithoclast was used for stone fragmentation.

Results

The mean (SD) operative time was shorter in the Silodosin group compared with the Placebo group, at 41.61 (4.67) vs 46.85 (4.6) min, respectively. Furthermore, advancing the ureteroscope to access the stone failed in a statistically significant number of patients in the Placebo group compared with the Silodosin group (13 vs two, respectively). The complication rate was significantly higher in the Placebo group compared with the Silodosin group (20% vs 6.4%, P = 0.036). Additionally, the need for postoperative analgesia was significantly lower in the Silodosin group compared with the Placebo group (8.1% vs 26.2%, P = 0.009).

Conclusion

Silodosin therapy prior to URS management of large distal ureteric stones seems to be associated with better advancing of the ureteroscope to access the stone, shorter procedure time, higher stone-free rate, lower incidence of complications, and lesser need for postoperative analgesia.

Assessment of factors affecting the spontaneous passage of lower ureteric calculus on the basis of lower ureteric calculus diameter, density, and plasma C- reactive protein level

Introduction:

The study aimed to evaluate the factors which affect the spontaneous passage of lower ureteric calculus on the basis of noncontrast computed tomography kidneys, ureters, and bladder (NCCT KUB) stone diameter, stone density, and plasma C-reactive protein (CRP) level.

Materials and Methods:

We conducted a prospective study of 200 patients with lower ureteric calculus 5–10 mm in size, from October 2015 to December 2016. All patients underwent NCCT KUB region with a 5 mm axial and reformatted coronal section. Edema just above the calculus and rim sign at the level of calculus and density of calculus is evaluated. Only scan with isolated, unilateral, solitary ureteric calculus was included in the final analysis and monitored up to 4 weeks, and plasma CRP is estimated in all patients to determine the clinical outcome.

Results:

A total of 200 patients (145 males, 55 females; mean age ± standard deviation, 34.73 ± 10.29) were included in the study. Lower ureteric calculus between 5–7 mm passed in 70% and 7–10 mm passed in 40%. There was 18% underestimation of maximum stone diameter in axial plane as compared to coronal plane. For spontaneous passage of calculus, craniocaudal (CC) diameter is more reliable then axial in NCCT. Rim sign and edema is absent in 64% of those passed spontaneous calculus. CRP level more than 2.45 mg/dl has low spontaneous expulsion rate. The stone with different HU passes through the ureter with same rate.

Conclusion:

Plasma CRP level and CC diameter and absence of rim sign on NCCT KUB are more reliable factors then density for spontaneous passage of ureteric calculus.

Prediction of spontaneous ureteral stone passage: Automated 3D-measurements perform equal to radiologists, and linear measurements equal to volumetric

OBJECTIVES

To compare the ability of different size estimates to predict spontaneous passage of ureteral stones using a 3D-segmentation and to investigate the impact of manual measurement variability on the prediction of stone passage.

METHODS

We retrospectively included 391 consecutive patients with ureteral stones on non-contrast-enhanced CT (NECT). Three-dimensional segmentation size estimates were compared to the mean of three radiologists' measurements. Receiver-operating characteristic (ROC) analysis was performed for the prediction of spontaneous passage for each estimate. The difference in predicted passage probability between the manual estimates in upper and lower stones was compared.

RESULTS

The area under the ROC curve (AUC) for the measurements ranged from 0.88 to 0.90. Between the automated 3D algorithm and the manual measurements the 95% limits of agreement were 0.2 ± 1.4 mm for the width. The manual bone window measurements resulted in a > 20 percentage point (ppt) difference between the readers in the predicted passage probability in 44% of the upper and 6% of the lower ureteral stones.

CONCLUSIONS

All automated 3D algorithm size estimates independently predicted the spontaneous stone passage with similar high accuracy as the mean of three readers' manual linear measurements. Manual size estimation of upper stones showed large inter-reader variations for spontaneous passage prediction.

KEY POINTS

• An automated 3D technique predicts spontaneous stone passage with high accuracy. • Linear, areal and volumetric measurements performed similarly in predicting stone passage. • Reader variability has a large impact on the predicted prognosis for stone passage.

Variability of renal colic management and outcomes in two Canadian cities

BACKGROUND

Some centres favour early intervention for ureteral colic while others prefer trial of spontaneous passage, and relative outcomes are poorly described. Calgary and Vancouver have similar populations and physician expertise, but differing approaches to ureteral colic. We studied 60-day hospitalization and intervention rates for patients having a first emergency department (ED) visit for ureteral colic in these diverse systems.

METHODS

We used administrative data and structured chart review to study all Vancouver and Calgary patients with an index visit for ureteral colic during 2014. Patient demographics, arrival characteristics and triage category were captured from ED information systems, while ED visits and admissions were captured from linked regional hospital databases. Laboratory results were obtained from electronic health records and stone characteristics were abstracted from diagnostic imaging reports. Our primary outcome was hospitalization or urological intervention from 0 to 60 days. Secondary outcomes included ED revisits, readmissions and rescue interventions. Time to event analysis was conducted and Cox Proportional Hazards modelling was performed to adjust for covariate imbalance.

RESULTS

We studied 3283 patients with CT-defined stones. Patient and stone characteristics were similar for the cities. Hospitalization or intervention occurred in 60.9% of Calgary patients and 31.3% of Vancouver patients (p<0.001). Calgary patients had higher index intervention rates (52.1% v. 7.5%), and experienced more ED revisits and hospital readmissions during follow-up. The data suggest that outcome events were associated with overtreatment of small stones in one city and undertreatment of large stones in the other.

CONCLUSIONS

An early interventional approach was associated with higher ED revisit, hospitalization and intervention rates. If these events are markers of patient disability, then a less interventional approach to small stones and earlier definitive management of large stones may reduce system utilization and improve outcomes for patients with acute ureteral colic.

Size matters: The width and location of a ureteral stone accurately predict the chance of spontaneous passage

Objectives

To determine how to most accurately predict the chance of spontaneous passage of a ureteral stone using information in the diagnostic non-enhanced computed tomography (NECT) and to create predictive models with smaller stone size intervals than previously possible.

Methods

Retrospectively 392 consecutive patients with ureteric stone on NECT were included. Three radiologists independently measured the stone size. Stone location, side, hydronephrosis, CRP, medical expulsion therapy (MET) and all follow-up radiology until stone expulsion or 26 weeks were recorded. Logistic regressions were performed with spontaneous stone passage in 4 weeks and 20 weeks as the dependent variable.

Results

The spontaneous passage rate in 20 weeks was 312 out of 392 stones, 98% in 0–2 mm, 98% in 3 mm, 81% in 4 mm, 65% in 5 mm, 33% in 6 mm and 9% in ≥6.5 mm wide stones.

The stone size and location predicted spontaneous ureteric stone passage. The side and the grade of hydronephrosis only predicted stone passage in specific subgroups.

Conclusion

Spontaneous passage of a ureteral stone can be predicted with high accuracy with the information available in the NECT. We present a prediction method based on stone size and location.

Key Points

• Non-enhanced computed tomography can predict the outcome of ureteral stones.

• Stone size and location are the most important predictors of spontaneous passage.

• Prediction models based on stone width or length and stone location are introduced.

• The observed passage rates for stone size in mm-intervals are reported.

• Clinicians can make better decisions about treatment.

The Role of the Tamsulosin in the Medical Expulsion Therapy for Distal Ureteral Stones

BACKGROUND

This research aims to evaluate the role of tamsulosin in the medical expulsion therapy for distal ureteral stones, including her effects in stone expulsion time, expulsion rates, stone size, pain episodes and analgesic dosage usage.

MATERIAL AND METHODS

The 104 patients with distal ureteral calculi were examined, with the size of the stones 4-10 mm. They were randomly divided into two groups: study group (n=52), received tamsulosin 0.4 mg in morning, for 28 days, analgesic (diclofenac 75 mg), high fluid intake and Control group (n=52) received analgesic (diclofenac 75 mg), high fluid intake.

RESULTS

There is no significant difference between groups, based on sex (P=0.835) and age (P=0.987). Average size of the stones was 6.5 mm (SD ± 1.6 mm), with no significant difference (P=0.996). Stone expulsion rate is 90.4% in the study group and 71.2% from the control group, with statistical significance (P=0.023). The average time of the expulsion of stones in the study group was 9.6 days (SD ± 7.1 days), control group 13.7 days (SD ± 7.3 days), with statistical significance, (P=0.034). Average dose of analgesics in the study group was 63.7 mg (SD ± 45.2 mg), control group is 109.2 (SD ± 53.3), with statistical significance (P=0.019).

CONCLUSION

Our study reveals that tamsulosin is efficient for the treatment of distal ureteral stones. Tamsulosin decrease the number of ureteral colic episodes, by acting as a spasmolytic, increase and hasten stone expulsion rates, reduce days of stone expulsion, decrease analgesic dose usage.

Some Work on the Diagnosis and Management of Kidney Stones with Ultrasound

Ultrasound is currently the only noninvasive technology able to completely diagnose and manage kidney stones.

Pharmacologic Expulsive Treatment of Ureteral Calculi

Objective:

TO evaluate the role of nifedipine and the α1-adrenoreceptor antagonists tamsulosin, terazosin, and doxazosin in the expulsive treatment of ureteral calculi.

Data Sources:

Literature was searched via MEDLINE (1966–February 2006) with subsequent bibliographic review. MeSH headings included ureteral calculi, nifedipine, doxazosin, and adrenergic α-antagonists. Key terms were ureteral calculi, nifedipine, tamsulosin, terazosin, and doxazosin.

Study Selection and Data Extraction:

Trials evaluating nifedipine, tamsulosin, terazosin, and doxazosin for expulsion of ureteral stones were reviewed. All were published in English-language, peer-reviewed journals.

Data Synthesis:

Several trials have evaluated the effects of nifedipine and tamsulosin on ureteral stone passage rates and mean time to stone passage in stones no larger than 15 mm. In 28 day trials, the rates of ureteral stone passage were 35–70% in the control groups compared with 77.1–80% in patients treated with nifedipine and 79.3–100% in patients treated with tamsulosin. Average number of days to stone passage in the control groups was 4.6–20, and the time to stone passage was only 5–9.3 days in patients receiving nifedipine and 2.7–7.9 days in those receiving tamsulosin. The stone passage rates and time to stone passage appeared to be similar in one trial that compared tamsulosin with terazosin and doxazosin. Limited data suggest that these agents may have a role as adjuncts to shock wave lithotripsy. Adverse drug reactions were uncommon.

Conclusions:

Nifedipine, tamsulosin, terazosin, and doxazosin are safe and effective options in enhancing ureteral stone expulsion in selected patients with uncomplicated presentations.

Alpha blockers for treatment of ureteric stones: systematic review and meta-analysis

OBJECTIVE

 To investigate the efficacy and safety of alpha blockers in the treatment of patients with ureteric stones.

DESIGN

 Systematic review and meta-analysis.

DATA SOURCES

 Cochrane Central Register of Controlled Trials, Web of Science, Embase, LILACS, and Medline databases and scientific meeting abstracts to July 2016.

REVIEW METHODS

 Randomized controlled trials of alpha blockers compared with placebo or control for treatment of ureteric stones were eligible. : Two team members independently extracted data from each included study. The primary outcome was the proportion of patients who passed their stone. Secondary outcomes were the time to passage; the number of pain episodes; and the proportions of patients who underwent surgery, required admission to hospital, and experienced an adverse event. Pooled risk ratios and 95% confidence intervals were calculated for the primary outcome with profile likelihood random effects models. Cochrane Collaboration's tool for assessing risk of bias and the GRADE approach were used to evaluate the quality of evidence and summarize conclusions.

RESULTS

 55 randomized controlled trials were included. There was moderate quality evidence that alpha blockers facilitate passage of ureteric stones (risk ratio 1.49, 95% confidence interval 1.39 to 1.61). Based on a priori subgroup analysis, there seemed to be no benefit to treatment with alpha blocker among patients with smaller ureteric stones (1.19, 1.00 to 1.48). Patients with larger stones treated with an alpha blocker, however, had a 57% higher risk of stone passage compared with controls (1.57, 1.17 to 2.27). The effect of alpha blockers was independent of stone location (1.48 (1.05 to 2.10) for upper or middle stones; 1.49 (1.38 to 1.63) for lower stones). Compared with controls, patients who received alpha blockers had significantly shorter times to stone passage (mean difference -3.79 days, -4.45 to -3.14; moderate quality evidence), fewer episodes of pain (-0.74 episodes, -1.28 to -0.21; low quality evidence), lower risks of surgical intervention (risk ratio 0.44, 0.37 to 0.52; moderate quality evidence), and lower risks of admission to hospital (0.37, 0.22 to 0.64; moderate quality evidence). The risk of a serious adverse event was similar between treatment and control groups (1.49, 0.24 to 9.35; low quality evidence).

CONCLUSIONS

 Alpha blockers seem efficacious in the treatment of patients with ureteric stones who are amenable to conservative management. The greatest benefit might be among those with larger stones. These results support current guideline recommendations advocating a role for alpha blockers in patients with ureteric stones.

SYSTEMATIC REVIEW REGISTRATION

 PROSPERO registration No CRD42015024169.

Sex-related Differences in Emergency Department Renal Colic Management: Females Have Fewer Computed Tomography Scans but Similar Outcomes

BACKGROUND

Sex-related differences occur in many areas of medicine. Emergency department (ED) studies have suggested differences in access to care, diagnostic imaging use, pain management, and intervention. We investigated sex-based differences in the care and outcomes for ED patients with acute renal colic.

METHODS

This was a multicenter population-based retrospective observational cohort study using administrative data and supplemented by structured chart review. All patients seen in Calgary Health Region EDs between January 1 and December 31, 2014, with an ED diagnosis of renal colic based on the following ICD-10 codes were eligible for inclusion: calculus of kidney (N200), calculus of ureter (N201), calculus of kidney with calculus of ureter (N202), hydronephrosis with renal and ureteral calculous obstruction (N132), unspecified renal colic (N23), and unspecified urinary calculus (N209). ED visit data and test results were accessed in the regional ED clinical database. Stone characteristics were captured from diagnostic imaging reports. Regional hospital databases were used to identify subsequent ED encounters, hospital admissions, and surgical procedures within 60 days. Outcomes were stratified by sex. The primary outcome, intended as a marker of overall effectiveness of ED care, was the unscheduled 7-day ED revisit rate among patients who were discharged home after their index ED visit. Secondary outcomes included ED pain management as reflected by administration of narcotics or intravenous nonsteroidals, the performance of advanced imaging-either ultrasound (US) or computed tomography (CT), and the proportion of patients who required hospitalization or surgical intervention within 60 days.

RESULTS

From January 1 to December 31, 2014, a total of 3,104 eligible patients were studied: 1,111 women (35.8%) and 1,993 men (64.2%). Baseline characteristics, access times, analgesic use, and admission rates were similar in both groups. Men were more likely to have CT (68.9% vs. 58.5%, difference = 10.4%, 95% confidence interval [CI] = 6.8 to 14.0) while women were more likely to have US (20.8% vs. 9.6%, difference = 11.2%, 95% CI = 8.4 to 13.9). At 7 days, 17.9% of women and 19.0% of men who were discharged after their index ED visit required an ED revisit (difference = 1.1%, 95% CI = -2.8 to 4.9). Men were more likely to be hospitalized at 7 days (9.8% vs. 6.5%, difference = 3.3%, 95% CI = 0.6 to 6.0).

CONCLUSION

This study shows greater reliance on US in females but no other sex-specific differences in the management of ED patients with acute renal colic. Higher CT use in men was not associated with improved outcomes, and we found no important differences in access to care, diagnostic or treatment intensity, or revisit rates as a marker of care effectiveness.

Tamsulosin versus tadalafil as a medical expulsive therapy for distal ureteral stones: A prospective randomized study

PURPOSE

This study aimed to compare the safety and efficacy of tamsulosin and tadalafil as medical expulsive therapy for distal ureteral stones.

MATERIALS AND METHODS

This prospective randomized study was conducted at the Department of Urology of Bir Hospital over a period of 12 months in patients with distal ureteral stones sized 5 to 10 mm. Patients were randomly divided into 2 groups: group A received tamsulosin 0.4 mg and group B received tadalafil 10 mg at bedtime for 2 weeks. Stone expulsion rate, number of ureteric colic episodes and pain score, analgesic requirements, and adverse drug effects were noted in both groups. Statistical analyses were performed by using Student t-test and chi-square test.

RESULTS

Altogether 85 patients, 41 in group A and 44 in group B, were enrolled in the study. The patients' average age was 31.72±12.63 years, and the male-to-female ratio was 1.5:1. Demographic profiles, stone size, and baseline investigations were comparable between the 2 groups. The stone expulsion rate was significantly higher in the tadalafil group than in the tamsulosin group (84.1% vs. 61.0%, p=0.017). Although the occurrence of side effects was higher with tadalafil, this difference was not significant (p=0.099). There were no serious adverse effects.

CONCLUSIONS

Tadalafil has a significantly higher stone expulsion rate than tamsulosin when used as a medical expulsive therapy for distal ureteral stones sized 5-10 mm. Both drugs are safe, effective, and well tolerated with minor side effects.

Comparative efficacy of tadalafil versus tamsulosin as the medical expulsive therapy in lower ureteric stone: a prospective randomized trial

Introduction

In recent years, medical expulsive therapy has been used in the management of distal ureteric stones as a supplement to conservative treatment. Therefore, we conducted a prospective randomized study to evaluate the possible role of tadalafil individually in comparison with proven tamsulosin therapy in ureteric stone expulsion.

The aim of this study is to compare the safety and efficacy of a phosphodiesterase-5 inhibitor (tadalafil) and an α-1 blocker (tamsulosin) as medical expulsive therapy for distal ureteric calculi.

Material and methods

Between August 2014 and October 2015, 207 patients who presented with distal ureteric stones of size 5–10 mm were randomly divided into two groups: tadalafil (Group A) and tamsulosin (Group B). Therapy was given for a maximum of 4 weeks. Stone expulsion rate, time to stone expulsion, analgesic use, number of hospital visits for pain, follow-up, endoscopic treatment and adverse effects of drugs were noted. Both groups were compared for normally distributed data by percentage, analysis of variance, and T-test. All the classified and categorical data were analyzed for both groups using the chi-square test.

Results

A statistically significant expulsion rate of 84.0% in Group A compared with 68.0% in Group B (P value = 0.0130), and shorter stone expulsion time in Group A (14.7±3.8) in comparison to Group B (16.8 ±4.5) was observed. Statistically significant differences were noted in renal colic episodes and analgesic requirement in Group A than Group B. No serious adverse effects were noted.

Conclusions

Tadalafil is safe, efficacious, and well tolerated as medical expulsive therapy for distal ureteric stones. This study showed that tadalafil increases ureteric stone expulsion quite significantly along with better control of pain and significantly lower analgesic requirement.

[CLINICAL FACTORS ASSOCIATED WITH SPONTANEOUS PASSAGE OF URETER STONES IN CONSERVATIVE MANAGEMENT: 6 mm IN MAXIMAL STONE SIZE MEASURED BY ULTRASONOGRAPHY CAN BE A PREDICTIVE BORDER]

(Purpose) To date there was no consensus regarding expectant size of stone and time to expulsion in the conservative treatment of ureter stones. The aim of this study was to find the clinical factors associated with stone passage by evaluating the outcome of ureter stones with expectant management in Japanese. (Materials and methods) A total of 679 ureter stone cases who visited our hospital with acute real colic and/or hematuria between 2009 and 2013, and who had decided to be treated by expectant management with or without medical expulsive therapy were enrolled in this study. All cases were examined size, location and presence of stone, and degree of hydronephrosis with ultrasonography. The examined data plus clinical data such as gender, age, side and body mass index were analyzed to find the factors related to spontaneous passage of ureter stones. Statistical analysis was performed to predict whether the factors were associated with the ureteral stone expulsion or not. (Results) Accumulated residual stone curve using Kaplan-Meier method showed time to 50%-expulsion as 15.7 days in cases with stone size no more than 6.0 mm and that as 21.8 days in those with greater than 6.0 mm, and time to 50%-expulsion as 28.8 days in cases with upper ureter stone whereas 15.6 days in those with middle or distal ureter stone. Analysis in groups with 1 mm-interval in stone size showed statistical significance only when compared 5-6 mm group with 6-7 mm group in size. Multivariate analysis showed stone size and location as statistically significant and independent factors to predict time to expulsion within 30 days. (Conclusion) Stone size and location was statistically reconfirmed to be associated with spontaneous passage in expectant management of ureter stones. This study statistically demonstrated the possibility that 6 mm in maximal stone size measured by ultrasonography can be a predictive border. 75% of ureter stones within 6 mm in maximal size measured by ultrasonography may expect to be expelled within 30 days.

Efficacy and safety of silodosin in the medical expulsion therapy for distal ureteral calculi: a systematic review and meta-analysis

AIMS

Using a selective α-adrenoceptor blocker for medical expulsive therapy (MET) is an effective treatment approach widely used for ureteral stones. The aim of the review was to assess the efficacy and safety of silodosin in medical expulstion therapy compared with placebo and tamsulosin.

METHODS

A systematic search was performed in PubMed, Cochrane Library and Embase to identify randomized controlled trials that compared silodosin with a placebo or tamsulosin for ureteral calculi.

RESULTS

Eight publications involving a total of 1048 patients were used in the analysis, which compared silodosin with placebo and tamsulosin. We found that silodosin was effective in treating ureteral calculi in our meta-analysis and was superior to tamsulosin in its efficacy. The expulsion rate of all ureteral stones (OR 1.59, 95% CI 1.08, 2.36, P = 0.02), the expulsion rate of distal ureteral stones (OR 2.82, 95% CI 1.70, 4.67, P < 0.0001) and the expulsion time (days) of distal ureteral stones (standard mean difference (SMD) -4.71, 95% CI -6.60, -2.83, P < 0.00001) indicated that silodosin was more effective than the placebo. Moreover, expulsion rate (OR 2.54, 95% CI 1.70, 3.78, P < 0.00001), expulsion time (days) (SMD -2.64, 95% CI -3.64, -1.64, P < 0.00001) and pain episodes (P < 0.00001) indicated that silodosin was more effective than the tamsulosin. Even though silodosin had a significant increase in abnormal ejaculation compared with tamsulosin, no significant differences were observed for complications (OR 1.00, 95% CI 0.58, 1.74, P = 1.00).

CONCLUSIONS

This meta-analysis indicated that silodosin was superior to placebo or tamsulosin in the efficacy for distal ureteral calculi with better control of pain. The safety profile of silodosin was similar to tamsulosin though retrograde ejaculation was worse for silodosin use. We conclude that silodosin might have potential as a MET for ureteral stones.

Can ureteral stones cause pain without causing hydronephrosis?

INTRODUCTION

While computerized tomography (CT) is the gold standard for diagnosis of ureterolithiasis, ultrasound is a less costly and radiation-free alternative which is commonly used to evaluate patients with ureteral colic. The purpose of this study was to evaluate the frequency with which patients with ureteral stones and renal colic demonstrate hydronephrosis in order to better understand the evaluation of these patients.

METHODS

Two hundred and forty-eight consecutive patients presenting with ureteral colic and diagnosed with a single unilateral ureteral stone on CT scan in an urban tertiary care emergency department were retrospectively reviewed. Radiology reports were reviewed for stone size, diagnosis, and degree of hydronephrosis.

RESULTS

Of the 248 patients evaluated for suspected ureteral stone, 221 (89.1 %) demonstrated any hydronephrosis, while 27 (10.9 %) did not. Hydronephrosis grade, available in 194 patients, was as follows: mild-70.6 %, moderate-27.8 %, and severe-1.5 %. Mean patient age was 47.0 years (SD 15.5), gender distribution was 35.9 % female and 64.1 % male, and mean stone axial diameter was 4.1 mm (SD 2.4). Stone location was as follows: ureteropelvic junction-4.1 %, proximal ureter-21 %, distal ureter-24.9 %, and ureterovesical junction-47.1 %. Axial stone diameter and coronal length (craniocaudal) were both significant predictors of degree of hydronephrosis (ANOVA, p < 0.001 for both). Age (ANOVA, p = NS), stone location (Chi square, p = NS), and gender (Chi square, p = NS) were not associated with degree of hydronephrosis.

CONCLUSIONS

In patients with ureteral stones and colic, nearly 11 % do not demonstrate any hydronephrosis and a majority (nearly 71 %) will demonstrate only mild hydronephrosis. Stone diameter appears to be related to degree of hydronephrosis, whereas age, gender, and stone location are not. The lower incidence of hydronephrosis for small stones causing renal colic may explain the lower diagnostic accuracy of ultrasound when compared to CT for detecting ureteral stones.

First in Human Clinical Trial of Ultrasonic Propulsion of Kidney Stones

PURPOSE

Ultrasonic propulsion is a new technology using focused ultrasound energy applied transcutaneously to reposition kidney stones. We report what are to our knowledge the findings from the first human investigational trial of ultrasonic propulsion toward the applications of expelling small stones and dislodging large obstructing stones.

MATERIALS AND METHODS

Subjects underwent ultrasonic propulsion while awake without sedation in clinic, or during ureteroscopy while anesthetized. Ultrasound and a pain questionnaire were completed before, during and after propulsion. The primary outcome was to reposition stones in the collecting system. Secondary outcomes included safety, controllable movement of stones and movement of stones less than 5 mm and 5 mm or greater. Adverse events were assessed weekly for 3 weeks.

RESULTS

Kidney stones were repositioned in 14 of 15 subjects. Of the 43 targets 28 (65%) showed some level of movement while 13 (30%) were displaced greater than 3 mm to a new location. Discomfort during the procedure was rare, mild, brief and self-limited. Stones were moved in a controlled direction with more than 30 fragments passed by 4 of the 6 subjects who had previously undergone a lithotripsy procedure. The largest stone moved was 10 mm. One patient experienced pain relief during treatment of a large stone at the ureteropelvic junction. In 4 subjects a seemingly large stone was determined to be a cluster of small passable stones after they were moved.

CONCLUSIONS

Ultrasonic propulsion was able to successfully reposition stones and facilitate the passage of fragments in humans. No adverse events were associated with the investigational procedure.

CT-Based Determination of Ureteral Stone Volume: A Predictor of Spontaneous Passage

INTRODUCTION AND OBJECTIVES

Which ureteral stone can pass spontaneously? It is hard to answer this question exactly. The size and location of the stone are the most important predictors. However, there is still a considerable gray zone that needs to be clarified. We try to identify the role of stone volume (SV) in the prediction of spontaneous passage (SP).

MATERIALS AND METHODS

Seventy-eight patients with a solitary ureteral stone were retrospectively evaluated. Ureter SV measurements were taken in three planes and were calculated using the following formula: V = (X) × (Y) × (Z) × 0.52. SVs, and the longest diameters (LDs) were compared between patients who passed stones spontaneously and those who needed intervention.

RESULTS

The SVs and LDs were significantly lower in patients who passed stones spontaneously than in patients who required intervention (41.2 ± 35.5 vs 128.1 ± 91.1 mm(3), p = 0.001; 5.7 ± 1.8 vs 7.4 ± 1.7 mm, p = 0.001). The optimum cutoff values were 7.0 mm and 52.6 mm(3) for the LD and SV, respectively. For those stones of ≤7 mm, the volumes of the stones that could and could not pass did not differ significantly. However, the volume of the stones >7.0 mm that could pass was significantly higher than of those that could not. SP was 30.6% for stones >7 mm; however, when we removed the stones >52.6 mm(3), SP increased to 75% for stones higher than 7 mm (p = 0.001).

CONCLUSIONS

To classify ureteral stones using only one parameter such as stone diameter may lead to heterogeneity within the group. SV may be used in addition to size to determine a more definite homogeneous group to predict SP more precisely.

Use of the Acoustic Shadow Width to Determine Kidney Stone Size with Ultrasound

PURPOSE

Ultrasound is known to overestimate kidney stone size. We explored measuring the acoustic shadow behind kidney stones combined with different ultrasound imaging modalities to improve stone sizing accuracy.

MATERIALS AND METHODS

A total of 45 calcium oxalate monohydrate stones were imaged in vitro at 3 different depths with the 3 different ultrasound imaging modalities of conventional ray line, spatial compound and harmonic imaging. The width of the stone and the width of the acoustic shadow were measured by 4 operators blinded to the true size of the stone.

RESULTS

Average error between the measured and true stone width was 1.4 ± 0.8 mm, 1.7 ± 0.9 mm, 0.9 ± 0.8 mm for ray line, spatial compound and harmonic imaging, respectively. Average error between the shadow width and true stone width was 0.2 ± 0.7 mm, 0.4 ± 0.7 mm and 0.0 ± 0.8 mm for ray line, spatial compound and harmonic imaging, respectively. Sizing error based on the stone width worsened with greater depth (p <0.001) while the sizing error based on the shadow width was independent of depth.

CONCLUSIONS

Shadow width was a more accurate measure of true stone size than a direct measurement of the stone in the ultrasound image (p <0.0001). The ultrasound imaging modality also impacted the measurement accuracy. All methods performed similarly for shadow size while harmonic imaging was the most accurate stone size modality. Overall 78% of the shadow sizes were accurate to within 1 mm, which is similar to the resolution obtained with clinical computerized tomography.

Two- and three-dimensional CT measurements of urinary calculi length and width: a comparative study

BACKGROUND

The standard imaging procedure for a patient presenting with renal colic is unenhanced computed tomography (CT). The CT measured size has a close correlation to the estimated prognosis for spontaneous passage of a ureteral calculus. Size estimations of urinary calculi in CT images are still based on two-dimensional (2D) reformats.

PURPOSE

To develop and validate a calculus oriented three-dimensional (3D) method for measuring the length and width of urinary calculi and to compare the calculus oriented measurements of the length and width with corresponding 2D measurements obtained in axial and coronal reformats.

MATERIAL AND METHODS

Fifty unenhanced CT examinations demonstrating urinary calculi were included. A 3D symmetric segmentation algorithm was validated against reader size estimations. The calculus oriented size from the segmentation was then compared to the estimated size in axial and coronal 2D reformats.

RESULTS

The validation showed 0.1 ± 0.7 mm agreement against reference measure. There was a 0.4 mm median bias for 3D estimated calculus length compared to 2D (P < 0.001), but no significant bias for 3D width compared to 2D.

CONCLUSION

The length of a calculus in axial and coronal reformats becomes underestimated compared to 3D if its orientation is not aligned to the image planes. Future studies aiming to correlate calculus size with patient outcome should use a calculus oriented size estimation.

Factors predicting the spontaneous passage of a ureteric calculus of ⩽10 mm

Objective

To evaluate the outcome of the expectant management of ureteric stones and to determine the factors predictive of the spontaneous passage of stones.

Patients and methods

We retrospectively reviewed the medical records of patients who had ureteric stones of ⩽10 mm and who were treated conservatively at our institutions during the period 2008–2013. The stone-passage rate and time, and different clinical, laboratory and radiological variables, were analysed.

Results

In all, 163 patients with ureteric stones were enrolled in the study, of whom 127 (77.9%) passed their stones spontaneously, with a mean (SD) passage time of 24.0 (8.09) days. The cumulative stone-passage rate was 1.6%, 15%, 41.7%, 72.4%, 89.8% and 98.4% at 7, 14, 21, 28, 35 and 42 days from the first presentation, respectively. Patients with a high pain-scale score, stones of ⩽5 mm, a lower ureteric stone, a high white blood cell count and those with absent computed tomography (CT) findings of perinephric fat stranding (PFS) and tissue-rim sign (TRS) had a higher likelihood of spontaneous stone passage. Patients with stones of ⩽5 mm, stones in the lower ureter and those with no PFS had a shorter spontaneous passage time. In a multivariate analysis the absence of PFS and TRS were the only significant predictors for spontaneous stone passage (P < 0.001 and 0.002, respectively).

Conclusions

The spontaneous ureteric stone-passage rate and time varies with different factors. The absence of CT findings of PFS and TRS are significant predictors for stone passage, and should be considered when choosing the expectant management.

The effect of tamsulosin in the medical treatment of distal ureteral stones

INTRODUCTION

Renal stones are common disorders that affect approximately 5% to 10% of the population and the incidence of renal stones is rising. Treatment of ureteral stones is an important part of urologists and minimally invasive procedures such as ESWL and ureteroscopy effectiveness has been proven in various studies. However, these methods are not completely safe and are expensive and can be complicated. Purpose of this study is to evaluate the effectiveness of tamsulosin in the medical treatment of distal ureteral stones.

PATIENTS & METHODS

A total of 96 patients with distal ureteral stones or UVj are randomly divided into two study group (50 patients) and control group (46 patients). Patients in the control group allowed to freely consuming fluids (hydration) and indomethacin 100 mg PRN. Study group in addition to indomethacin and daily analgesic 0.4 mg tamsulosin was administered. All subjects in terms of analgesic dose, duration of expulsion and expulsion were studied.

RESULTS

Spontaneous expulsion of stone was occurred in 62.5% (30 patients out of 46) of control group patients and 82% (41 patients out of 50) that there was no significant difference (P>0.05). Average time to fix the stone in control group 4.7 ± 8.03 days (range 2 to 28 days) and in the study group, 3.7 ± 5.70 days (range 1 to 23 days) is significantly different (P>0.05). The average amount of analgesic consumption in the control group was 2.3 ± 4.31 and in the study group was 1.48 ± 2.15 that showed significant differences (P<0.05).

CONCLUSION

In this study, although the addition of tamsulosin to conservative treatment of distal ureteral stones in the distal ureteral stone expulsion showed no significant difference between the two groups, but the reduction in the duration of expulsion, reduce pain and reduce the need for analgesic has been beneficial.

Tools to improve the accuracy of kidney stone sizing with ultrasound

PURPOSE

Ultrasound (US) overestimates stone size when compared with CT. The purpose of this work was to evaluate the overestimation of stone size with US in an in vitro water bath model and investigate methods to reduce overestimation.

MATERIALS AND METHODS

Ten human stones (3-12 mm) were measured using B-mode (brightness mode) US by a sonographer blinded to the true stone size. Images were captured and compared using both a commercial US machine and software-based research US device. Image gain was adjusted between moderate and high stone intensities, and the transducer-to-stone depth was varied from 6 to 10 cm. A computerized stone-sizing program was developed to outline the stone width based on a grayscale intensity threshold.

RESULTS

Overestimation with the commercial device increased with both gain and depth. Average overestimation at moderate and high gain was 1.9±0.8 and 2.1±0.9 mm, respectively (p=0.6). Overestimation increased an average of 22% with an every 2-cm increase in depth (p=0.02). Overestimation using the research device was 1.5±0.9 mm and did not vary with depth (p=0.28). Overestimation could be reduced to 0.02±1.1 mm (p<0.001) with the computerized stone-sizing program. However, a standardized threshold consistent across depth, system, or system settings could not be resolved.

CONCLUSION

Stone size is consistently overestimated with US. Overestimation increased with increasing depth and gain using the commercial machine. Overestimation was reduced and did not vary with depth, using the software-based US device. The computerized stone-sizing program shows the potential to reduce overestimation by implementing a grayscale intensity threshold for defining the stone size. More work is needed to standardize the approach, but if successful, such an approach could significantly improve stone-sizing accuracy and lead to automation of stone sizing.

The effect of smoking on spontaneous passage of distal ureteral stones

Background

Animal studies have shown that nicotine affects the peristalsis of the ureter. The aim of the study is to analyze the effect of smoking on spontaneous passage of distal ureteral stones.

Methods

88 patients in whom distal ureteral stone below 10 mm diameter diagnosed with helical computerized tomography enhanced images were reviewed. Patients were grouped as either smokers (n:33) or non smokers (n:50). Follow-up for spontaneous passage of stones was limited with 4 weeks. Patients did not receive any additional medical treatment other than non-steroid anti inflamatory drugs only during painful renal colic episodes.

Two groups were compared with the chi-square test in terms of passing the stone or not. Stone passage was confirmed with either the patient collecting the stone during urination or by helical CT.

Results

Smoking habits was present in 30(34%) patients and the frequency in both groups were similar (smokers: 23(76%) vs non-smokers: 46(79%)). Spontaneous passage of the stone was observed in 69(78%) patients. The two groups were comparable in terms of patien age, male to female ratio and stone size. Stone passage decreased as stone diameter increased. Total stone passage rates were similar in both groups (smokers: 76% vs. non-smokers: 79%) (p > 0.05). Passage of stones > 4 mm was observed in 46% and 67% of smokers and non-smokers respectively. However passage of stones with a diameter ≤ 4 mm were similar in both groups (smokers: 100% vs non-smokers: 92%) (p > 0.05).

Conclusion

Smoking has neither a favorable nor un-favorable effect on spontaneous passage of distal ureteral stones. However, spontaneous passage rates in patients with a stone diameter > 4 mm was lower in smokers. These results should be further confirmed with studies including larger numbers of patients.

Comparative efficacy of tamsulosin versus tamsulosin with tadalafil in combination with prednisolone for the medical expulsive therapy of lower ureteric stones: a randomized trial

PURPOSE

To compare the safety and efficacy of tamsulosin and tamsulosin with the phosphodiesterase-5 inhibitor tadalafil in combination with prednisolone as medical expulsive therapies for lower ureteric stones.

MATERIALS AND METHODS

Between July 2011 and December 2012, 62 adult patients presenting with distal ureteric stones sized 5 to 10 mm were randomized equally to treatment with tamsulosin (group A) or tamsulosin with tadalafil (group B). Therapy was given for a maximum of 6 weeks. In addition, patients in groups A and B were given 5-mg prednisolone once daily (maximum 1 week). The stone expulsion rate, time to stone expulsion, analgesic use, number of hospital visits for pain, follow-up and endoscopic treatment, and adverse effects of the drugs were noted. Statistical analyses were done by using Student t-test and chi-square test.

RESULTS

There was a higher expulsion rate (83.9% in group B and 74.2% in group A) and a lower time to expulsion in both treatment groups than in historical controls used in earlier studies. However, these results were not statistically significant (p=0.349, p=0.074, respectively). Statistically significant differences were noted in hospitalization for colic and analgesic requirement, which were less in group B than in group A. There were no serious adverse events. Another important finding was improvement in erectile function in group B.

CONCLUSIONS

Medical expulsive therapy for distal ureteric stones using tamsulosin and tadalafil with prednisolone is safe and efficacious. Also, the prescription of tadalafil in cases of erectile dysfunction with the development of lower ureteric stones may provide additional advantages.

The efficacy of tamsulosin vs. nifedipine for the medical expulsive therapy of distal ureteric stones: A randomised clinical trial

OBJECTIVES

To assess and compare, in a randomised clinical trial, the efficacy of tamsulosin and nifedipine as medical expulsive therapy for distal ureterolithiasis.

PATIENTS AND METHODS

In all, 128 symptomatic patients with stones in the juxtavesical tract of the ureter were randomly divided into group 1 (64 patients) receiving oral nifedipine sustained-release 30 mg/day, and group 2 (64 patients) receiving tamsulosin 0.4 mg/day. Both groups received oral prednisolone 30 mg/day for 10 days and diclofenac 75 mg intramuscularly on demand. Patients were assessed by weekly ultrasonography with or with no abdominal computed tomography, during a follow-up of 4 weeks. The stone passage rate and time, analgesic use, hospitalisation and endoscopic interventions were evaluated. The results were analysed statistically using appropriate tests.

RESULTS

The stone expulsion rate was 55% for group 1 and 80% for group 2 (P = 0.004). The mean stone size was 8.59 and 8.85 mm in groups 1 and 2, respectively. The mean expulsion time was 23 days for group 1 and 9 days for group 2 (P < 0.001). The mean number of diclofenac injections was 1.19 for group 1 and 0.42 for group 2 (P < 0.001). Eleven patients in group 1 vs. two in group 2 were hospitalised (P = 0.001). Twenty-six patients in group 1 and 13 in group 2 underwent ureteroscopy (P < 0.001).

CONCLUSIONS

Medical expulsive therapy with tamsulosin should be considered as a first-line treatment for index cases of distal ureterolithiasis with no complications. The use of tamsulosin provides better stone expulsion than does nifedipine.

Randomized controlled trial to compare the safety and efficacy of naftopidil and tamsulosin as medical expulsive therapy in combination with prednisolone for distal ureteral stones

Purpose

To compare the safety and efficacy of naftopidil and tamsulosin with prednisolone as medical expulsive therapy for distal ureteric stones.

Materials and Methods

Between July 2010 and March 2012, 120 adult patients presenting with distal ureteric stones of size 5 to 10 mm were randomized equally to tamsulosin (group A), naftopidil (group B) or watchful waiting (group C). Tamsulosin or naftopidil was given for a maximum of four weeks. In addition patients in group A and B were given 5 mg prednisolone once daily (maximum one week). Stone expulsion rate, time to stone expulsion, analgesic use, number of hospital visits for pain, follow-up and endoscopic treatment and adverse effects of drugs were noted. Statistical analyses were done using chi-square test, Mann-Whitney test and analysis of variance.

Results

There was a statistically higher expulsion rate in groups A (70%) and B (87.5%) as compared to group C (32.5%) (p<0.001). The expulsion rates were not statistically different between groups A and B (p=0.056). The mean time to expulsion was comparable between groups A and B but longer in group C. Analgesic use was significantly lower in groups A and B. Average number of hospital visits for pain, follow-up and endoscopic treatment was similar in all groups. There was no serious adverse event.

Conclusions

Medical expulsive therapy for the distal ureteric stones using either naftopidil or tamsulosin in combination with prednisolone is safe and efficacious.

Stone expulsion rate of small distal ureteric calculi could be predicted with plasma C-reactive protein

Ureteral stones tend to induce inflammatory lesions in the ureteric wall; such lesions may interfere with the probability of spontaneous ureteral stone passage. Plasma C-reactive protein (CRP) is an acute-phase protein whose serum level is increases in response to inflammation, as in ureteric inflammatory disorders induced by stone impaction. Patients with distal ureteric stones were included in this study. All patients were subjected to history taking KUB, urinary tract ultrasound, Non-contrast CT (NC-CTKUB) scan, and plasma CRP estimation. All patients received medical expulsive therapy. Patients were examined weekly using KUB and urinary tract ultrasound until spontaneous stone passage or intervention after 4 weeks. Patients who failed to expel the stone within 4 weeks underwent ureteroscopy. Spontaneous stone expulsion within 4 weeks was recorded in 129 patients (54.9 %), while 106 patients (45.1 %) underwent ureteroscopy for stone extraction. Patients with spontaneous stone expulsion had significantly lower serum CRP levels (16.45 + 2.58) than those who failed to pass the stone spontaneously (39.67 + 6.30). Receiver operator characteristic curve is used to determine CRP cut-off point for prediction of spontaneous ureteric stone expulsion. A cut-off point of 21.9 mg/L for CRP yielded appeared optimal for prediction of spontaneous ureteric stone expulsion. Medical expulsive therapy success for management of small distal ureteric calculi could be predicted with plasma CRP. Patients with CRP >21.9 mg/L have low stone expulsion rate and should directly be subjected for an immediate, minimally invasive ureteroscopy.

Role of white blood cell and neutrophil counts in predicting spontaneous stone passage in patients with renal colic

OBJECTIVE

To determine the clinical, imaging and laboratory variables that can predict spontaneous passage of ureteral stones causing renal colic and the role of white blood cell (WBC) and neutrophil counts for the prediction of spontaneous calculi passage.

PATIENTS AND METHODS

A total of 156 patients who were referred to the emergency department complaining of renal colic due to a ureteral stone entered the analysis. Several clinical, laboratory and imaging parameters were evaluated for their potential ability to predict stone passage in a time interval of 1 month. The study design had two objectives. Primarily we analyzed all patients irrespective of stone size and secondly we analyzed patients with calculi of 10 mm maximum length.

RESULTS

Spontaneous stone passage was observed in 96 (61.5%) patients in the overall population and in 84 (65.1%) of 129 patients with calculi <10 mm. Increased concentrations of serum WBCs and neutrophils at the time of the acute phase of a renal colic were associated with increased likelihood of spontaneous passage. In the multivariate analyses we found that WBC and neutrophil counts were the most important predictors of stone elimination.

CONCLUSIONS

Active surveillance of patients suffering from ureteral lithiasis is an acceptable option. Identifying the parameters which can predict those patients who will mostly benefit from this is of great importance. Based on our results, WBC and neutrophil counts should be considered when patients with renal colic secondary to ureteral calculi are evaluated since they can significantly add to spontaneous elimination prediction. Their consideration in addition to other important factors, like stone size and location, would maximize their predictive ability.

Expectant Management of Ureter Stones: Outcome and Clinical Factors of Spontaneous Passage in a Single Institution's Experience

Purpose

The aim of this study was to evaluate the outcome of ureter stones with expectant management and the clinical factors associated with stone passage in Koreans.

Materials and Methods

We reviewed the charts of patients who visited the emergency room or urological office of our institution with acute renal colic between 2001 and 2008. A total of 656 ureter stone formers were enrolled in this study who had decided to be treated by expectant management. Clinical data such as gender, age, size and location of the stone, body mass index, and previous stone history were analyzed to find the factors related to spontaneous passage of ureter stones.

Results

Of the 656 ureter stones, 566 stones (86.3%) were spontaneously expelled. Mean duration of follow-up was 17.5 days (range, 1 to 100 days). Mean time to stone passage was 6.8 days for stones less than 2 mm in size, 12.6 days for stones 2 to 4 mm, 14.8 days for stones 4 to 6 mm, and 21.8 days for stones 6 to 8 mm (p<0.001). The cumulative spontaneous passage rate was 55.3% in 7 days, 73.7% in 14 days, 88.5% in 28 days, and 97.7% in 60 days after the first attack. A total of 90 patients (13.7%) required interventions because of symptom relapse or renal deterioration that was related to the location and size of the stone (each, p<0.001). The more proximal the location and the larger the stone was than 6 mm, the less the chance of spontaneous passage (each, p<0.001).

Conclusions

Size and location of ureter stones are the most important factors for predicting the spontaneous passage of the stone. If a patient has a distal ureter stone of less than 6 mm in size, it is acceptable for the urologist to observe for spontaneous passage for 2 months.

The efficacy of tamsulosin in lower ureteral calculi

Context:

There has been a paradigm shift in the management of ureteral calculi in the last decade with the introduction of new less invasive methods, such as ureterorenoscopy and extracorporeal shock wave lithotripsy (ESWL).

Aims:

Recent studies have reported excellent results with medical expulsive therapy (MET) for distal ureteral calculi, both in terms of stone expulsion and control of ureteral colic pain.

Settings and Design:

We conducted a comparative study in between watchful waiting and MET with tamsulosin.

Materials and Methods:

We conducted a comparative study in between watchful waiting (Group I) and MET with tamsulosin (Group II) in 60 patients, with a follow up of 28 days.

Statistical Analysis:

Independent 't' test and chi-square test.

Results:

Group II showed a statistically significant advantage in terms of the stone expulsion rate. The mean number of episodes of pain, mean days to stone expulsion and mean amount of analgesic dosage used were statistically significantly lower in Group II (P value is 0.007, 0.01 and 0.007, respectively) as compared to Group I.

Conclusions:

It is concluded that MET should be considered for uncomplicated distal ureteral calculi before ureteroscopy or extracorporeal lithotripsy. Tamsulosin has been found to increase and hasten stone expulsion rates, decrease acute attacks by acting as a spasmolytic, reduces mean days to stone expulsion and decreases analgesic dose usage.

Making renal stones change size-impact of CT image post processing and reader variability

OBJECTIVES

The objectives of this study were to quantify the impact of image post-processing parameters on the apparent renal stone size, and to quantify the intra- and inter-reader variability in renal stone size estimation.

METHODS

Fifty CT datasets including a renal or ureteral stone were included retrospectively during a prospective inclusion period. Each of the CT datasets was post-processed in different ways regarding slice thickness, slice increment and window setting. In the first part of the study a single reader repeated size estimations for the renal stones using different post-processing parameters. In the intra-reader variability experiment one reader reported size estimations for the same images with a one-week interval. The inter-reader variability data were obtained from 11 readers reporting size estimations for the same renal stones.

RESULTS

The apparent stone size differed according to image post-processing parameters with the largest mean differences seen with regard to the window settings experiment (1.5 mm, p < 0.001) and slice thickness (0.8 mm, p < 0.001). Changes in parameters introduced a bias and a pseudo-random variability. The inter-reader variability was considerably larger than the intra-reader variability.

CONCLUSION

Our results indicate a need for the standardisation of making measurements on CT images.