Ureteral Calculi

Burst Wave Lithotripsy (BWL) is a novel method of urinary stone fragmentation that uses multi-cycle bursts of low amplitude ultrasound to induce stone fracture. This is in contrast to traditional extracorporeal shock wave lithotripsy (SWL), which employs a brief single compression/tensile cycle of high amplitude (shock) waves to achieve stone fracture. This is a single-arm feasibility study to test the ability of BWL to comminute (fragment) stones in humans.

This is a single-center, observational study including a retrospective cohort and a prospective validation cohort. The study aims to identify independent risk factors for inflammatory ureteral polyps in patients with ureteral calculi and develop a preoperative predictive model. The retrospective part will analyze clinical and imaging data of patients treated at the First Hospital of Jilin University between 2018 and 2025. The prospective part is currently recruiting participants to validate the model. The primary outcome is the intraoperative diagnosis of inflammatory ureteral polyps.

This randomized controlled trial compares the efficacy and safety of four treatment strategies for ureteral stone expulsion: Mirabegron alone, Tamsulosin alone, a combination of both, and standard conservative care. Participants diagnosed with ureteral stones will be randomly assigned to one of these four groups. The primary objective is to evaluate the stone expulsion rate within 4 weeks. The study also assesses time to expulsion, pain intensity, analgesic use, and potential side effects.

This prospective multicenter randomized controlled trial will compare stent-related symptoms after placement of a ComfiJ ureteral stent versus a conventional double-J ureteral stent in adult patients undergoing unilateral ureteroscopy or retrograde intrarenal surgery for urinary stones when short-term postoperative ureteral stenting is clinically indicated. Eligible patients will be randomized intraoperatively after the operating surgeon confirms the need for postoperative stenting. The primary outcome will be the Ureteral Stent Symptom Questionnaire urinary symptoms domain score on postoperative day 14 before planned stent removal.

Acute calculous anuria is a urological emergency caused by ureteral stone obstruction in a solitary functioning kidney or bilateral ureteral obstruction. Urgent decompression of the upper urinary tract is required to restore urine drainage and prevent further renal impairment. This prospective randomized double-blind controlled trial will evaluate whether intravesical aminophylline can facilitate urgent retrograde ureteral stenting in adult patients with acute calculous anuria due to ureteral stones. Eligible patients will be randomly assigned to receive either intravesical aminophylline diluted in normal saline or placebo saline before attempted retrograde Double-J ureteral stent placement. The primary outcome is technical success, defined as successful placement of a Double-J ureteral stent across the obstructing stone without the need for percutaneous nephrostomy. Secondary outcomes include stenting time, intraoperative complications, renal function recovery, postoperative pain, analgesic requirement, and the need for alternative drainage.

Double-J ureteral stents are commonly inserted after ureteroscopy, but they may cause bothersome urinary symptoms, pain, sleep disturbance, and reduced quality of life. This prospective randomized assessor-blinded three-arm clinical trial will compare oral solifenacin, oral melatonin, and their combination for improving ureteral stent-related symptoms in adult patients after unilateral ureteroscopic lithotripsy with insertion of a unilateral Double-J ureteral stent. Participants will be randomized to receive solifenacin 5 mg once daily, melatonin 3 mg once nightly, or combined solifenacin 5 mg once daily plus melatonin 3 mg once nightly for 14 days after surgery. The primary outcome is the total Ureteral Stent Symptom Questionnaire score at postoperative Day 7. Secondary outcomes include total Ureteral Stent Symptom Questionnaire score at Day 14, change in questionnaire score between Day 7 and Day 14, Insomnia Severity Index score, Visual Analogue Scale pain score, adverse events, treatment compliance, and rescue analgesic consumption.

This study will evaluate whether intravesical aminophylline can facilitate semi-rigid ureteroscopic access in children with distal ureteral stones when the first gentle attempt to enter the ureter is unsuccessful. Children scheduled for semi-rigid ureteroscopy for distal ureteral stones will first undergo the standard gentle attempt to pass the ureteroscope through the ureteric orifice and intramural ureter. If access is achieved, the child will continue standard treatment and will not be randomized. If access is not achieved, the child will be randomized during the operation to receive either intravesical aminophylline or intravesical normal saline placebo. The study solution will be instilled into the bladder for approximately 5 minutes, then drained, and a second gentle ureteroscopic access attempt will be made. The main outcome is successful same-session passage of the intended semi-rigid ureteroscope without balloon dilation. The study will also assess the need for JJ stenting and deferred ureteroscopy, same-session stone treatment, operative outcomes, complications, and early aminophylline-related safety.

This study will compare L-citrulline and tamsulosin as medical expulsive therapy for adults with single distal ureteral stones. Eligible participants with a single distal ureteral stone measuring 5 to 10 mm will be randomly assigned to receive either oral L-citrulline 750 mg twice daily or oral tamsulosin 0.4 mg once daily. Treatment will continue until documented stone passage or completion of 4 weeks of therapy, whichever occurs first. Participants will be followed weekly for up to 4 weeks. The main outcome is stone expulsion within 4 weeks. The study will also assess time to stone expulsion, pain episodes, analgesic use, need for additional intervention, and adverse events.

This international multicenter retrospective cohort study aims to externally validate the URSL Predictive Angle, a novel CT-derived morphometric parameter, as an imaging biomarker for predicting intraoperative conversion risk during transurethral ureteroscopic lithotripsy (URSL) for ureteral calculi. Intraoperative conversion is defined as the unanticipated abandonment of the planned endoscopic approach due to unfavorable ureteral anatomy or stone impaction, necessitating recourse to open ureterolithotomy, laparoscopic ureterolithotomy, or ureteral stent placement with planned staged secondary intervention. Such conversions are associated with protracted operative duration, heightened anesthetic exposure, and increased physical, psychological, and financial burdens on patients. The URSL Predictive Angle is a geometric parameter derived from preoperative coronal CT reformations that quantifies the degree of local ureteral angulation induced by an impacted calculus. Preliminary single-center data demonstrated robust predictive fidelity of this metric with an area under the ROC curve of 0.861 and an optimal discriminatory threshold of 131.8° yielding a sensitivity of 82% and a specificity of 88%. This study will enroll eligible patients from multiple domestic and international tertiary care hospitals who underwent URSL for ureteral calculi between January 1, 2018, and December 31, 2025. The primary outcome is intraoperative conversion of surgical approach. The predictive performance of the URSL angle will be evaluated using ROC curve analysis with AUC calculation. Propensity score matching and multivariable logistic regression will be employed to address potential confounding. This study is registered as a patient registry with a cohort model. Data collection is retrospective, involving abstraction from electronic medical records, operative logs, and PACS. A waiver of informed consent has been requested based on the retrospective design, minimal risk determination, stringent anonymization procedures, and impracticability of obtaining individual consent.

Investigating the differences in gut microbiota composition and tryptophan metabolite levels between kidney stone patients and healthy individuals, with special focus on: 1. Comparing the gut microbiota composition between kidney stone patients and healthy controls, with emphasis on analyzing the relative abundance of Lactobacillus salivarius 2. Comparing the differences in tryptophan metabolite levels such as indole-3-carboxylic acid (ICA) and kynurenine (Kyn) in serum between the two groups 3. Exploring the correlation between gut microbiota composition and tryptophan metabolite levels 4. Analyzing the influence of different environmental conditions (seasons, temperature and humidity) on gut microbiota and metabolite levels

The goal of this clinical trial is to learn if the combination of super pulsed thulium fiber laser (sTFL) with a flexible negative pressure suction sheath is more effective and safer than sTFL with a conventional sheath in treating kidney stones and/or ureteral stones. The main questions it aims to answer are: Does the sTFL with a flexible negative pressure suction sheath have a higher stone - free rate than the sTFL with a conventional sheath? Does the sTFL with a flexible negative pressure suction sheath have fewer complications than the sTFL with a conventional sheath? Researchers will compare the two treatment groups to see if there are differences in stone - free rate and complication rates. Participants will: Undergo ureteroscopic lithotripsy surgery. In the experimental group, have a flexible negative pressure suction sheath inserted along a guidewire to the stone site under general anesthesia, then have a ureteroscope inserted through the sheath to the stone site, and have the stone fragmented by sTFL with a power setting of 0.8J and a frequency of 12 - 20Hz while the fragments are removed by negative pressure suction. In the control group, have a conventional sheath inserted to the upper ureter or the ureteropelvic junction under general anesthesia, then have a ureteroscope inserted through the sheath to the stone site, and have the stone fragmented by sTFL with a power setting of 0.8J and a frequency of 12 - 20Hz and the fragments removed by a stone basket.