[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"health-studies-list:{\"conditionNormalized\":\"ureteral-access-sheath\",\"overallStatus\":[\"RECRUITING\",\"AVAILABLE\",\"NOT_YET_RECRUITING\"],\"orderBy\":\"LastUpdateSubmitDate:desc\",\"size\":25,\"offset\":0}":3,"health-study-condition:ureteral-access-sheath":29},{"pageToken":4,"total":5,"offset":6,"count":5,"results":7},null,2,0,[8,42],{"id":9,"slug":10,"hasResults":11,"nctId":12,"briefTitle":13,"officialTitle":14,"acronym":4,"eligibilityCriteria":15,"healthyVolunteers":11,"sex":16,"minAge":17,"maxAge":4,"enrollmentInfo":18,"targetDuration":4,"studyType":21,"phases":4,"briefSummary":22,"conditions":23,"keywords":4,"overallStatus":30,"whyStopped":4,"lastUpdateSubmitDate":31,"lastUpdatePostDateStruct":32,"startDateStruct":35,"completionDateStruct":36,"leadSponsor":38,"locationsCount":41},"100651965","long-term-safety-of-uas-assisted-vs-sheathless-rirs-in-non-prestented-patients-100651965",false,"NCT07767773","Long-term Safety of UAS-assisted vs Sheathless RIRS in Non-prestented Patients","Long-Term Safety Outcomes of Ureteral Access Sheath-Assisted Versus Sheathless Retrograde Intrarenal Surgery for Renal Stones ≤20 mm in Non-Prestented Patients: A Retrospective Comparative Cohort Study With Active Follow-up","Inclusion Criteria:\n\n* Age ≥18 years at time of index RIRS.\n* Primary RIRS performed at Al-Azhar University Hospitals between Jan 1, 2020 and Dec 31, 2025.\n* Renal stone(s) with maximum diameter ≤20 mm on preoperative imaging.\n* No ipsilateral ureteral stent or nephrostomy before index RIRS.\n* Documented operative record specifying whether a UAS was used.\n* At least 12 months elapsed since index RIRS.\n* Available contact information allowing invitation for active follow-up.\n\nExclusion Criteria:\n\n* Primary ureteral stone treated during the same procedure.\n* Staghorn or \\>20 mm stone burden.\n* Prior ipsilateral ureteral stricture or reconstructive surgery.\n* Congenital renal\u002Fureteral anomalies affecting outcome (e.g., horseshoe kidney, duplicated system).\n* Incomplete operative or preoperative imaging records that preclude determination of eligibility or exposure (UAS use).\n* Additional ipsilateral ureteral procedure during follow-up that independently causes ureteral narrowing.\n* Refusal to participate in active follow-up or failure to attend after repeated attempts.","ALL","18 Years",{"count":19,"type":20},1200,"ESTIMATED","OBSERVATIONAL","This retrospective comparative cohort study will include adult patients who underwent primary RIRS for renal stones ≤20 mm at Al-Azhar University Hospitals between January 2020 and December 2025. Patients will be classified by whether a ureteral access sheath (UAS) was used during the index RIRS, and all eligible patients will be invited for active long-term follow-up (minimum 12 months) to assess the composite outcome of delayed ipsilateral ureteral stricture or new\u002Fprogressive ipsilateral hydronephrosis and other safety and efficacy outcomes. Propensity-score methods and adjusted regression analyses will be used to control confounding.",[24,25,26,27,28,29],"Renal Stone Disease","Ureteral Stricture","Hydronephrosis","Urolithiasis","Retrograde Intrarenal Surgery","Ureteral Access Sheath","RECRUITING","2026-08-16",{"date":33,"type":34},"2026-08-18","ACTUAL",{"date":31,"type":34},{"date":37,"type":20},"2027-12-25",{"name":39,"class":40},"Al-Azhar University","OTHER",1,{"id":43,"slug":44,"hasResults":11,"nctId":45,"briefTitle":46,"officialTitle":47,"acronym":48,"eligibilityCriteria":49,"healthyVolunteers":11,"sex":16,"minAge":17,"maxAge":4,"enrollmentInfo":50,"targetDuration":4,"studyType":52,"phases":53,"briefSummary":55,"conditions":56,"keywords":4,"overallStatus":30,"whyStopped":4,"lastUpdateSubmitDate":59,"lastUpdatePostDateStruct":60,"startDateStruct":62,"completionDateStruct":64,"leadSponsor":66,"locationsCount":41},"100602499","phase-4-alpha-blockers-prior-to-ureteral-access-sheath-placement-in-flexible-ureteroscopy-a-randomized-prospective-study-100602499","NCT07124299","Alpha-Blockers Prior to Ureteral Access Sheath Placement in Flexible Ureteroscopy: A Randomized Prospective Study","Prospective, Randomized Study on the Efficiency of Alpha-Blockers Prior to Ureteral Sheath Placement in Flexible Ureterolithotripsy","ALFA-URS","Inclusion Criteria:\n\n* Age ≥ 18 years\n* Diagnosis of nephrolithiasis with surgical indication for flexible ureterorenolithotripsy\n* Ability to provide written informed consent\n\nExclusion Criteria:\n\n* Age \\\u003C 18 years\n* Pregnancy\n* History of ureteral stricture, prior ureteral reconstructive surgery, and\u002For abdominal or pelvic radiotherapy\n* Prior ureteroscopy or ipsilateral double-J stent placement within the past 3 months\n* Chronic use of alpha-blockers for benign prostatic hyperplasia or medical expulsive therapy for ureteral stones",{"count":51,"type":20},140,"INTERVENTIONAL",[54],"PHASE4","This study aims to evaluate whether the use of alpha-blockers before flexible ureterorenolithotripsy facilitates the passage of the ureteral access sheath. The trial will enroll adult patients diagnosed with kidney stones who are scheduled for flexible ureteroscopy. Participants will be randomly assigned to receive or not receive alpha-blockers for seven days before surgery. The primary outcome is the rate of successful sheath placement without the need for a second procedure. Secondary outcomes include the incidence of ureteral injuries and the need for additional surgical interventions. The goal is to improve surgical efficiency and patient outcomes in the treatment of kidney stones.",[57,58,29],"Nephrolithiasis","Alpha Blocker","2025-08-09",{"date":61,"type":34},"2025-08-15",{"date":63,"type":34},"2024-01-01",{"date":65,"type":20},"2026-02-01",{"name":67,"class":40},"Pedro de Figueiredo Buchalla"]