[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"health-study-detail:100652436":3},{"organization":4,"armGroups":7,"interventions":19,"overallOfficials":29,"centralContacts":34,"locations":39,"responsibleParty":56,"collaborators":11,"id":58,"slug":59,"hasResults":60,"nctId":61,"briefTitle":62,"officialTitle":63,"acronym":11,"eligibilityCriteria":64,"healthyVolunteers":60,"sex":65,"minAge":66,"maxAge":67,"enrollmentInfo":68,"targetDuration":11,"studyType":71,"phases":72,"briefSummary":74,"conditions":75,"keywords":11,"overallStatus":42,"whyStopped":11,"lastUpdateSubmitDate":77,"lastUpdatePostDateStruct":78,"startDateStruct":81,"completionDateStruct":82,"leadSponsor":84,"locationsCount":85},{"fullName":5,"class":6},"Al-Azhar University","OTHER",[8,14],{"label":9,"type":10,"description":11,"interventionNames":12},"Pre-stenting group","EXPERIMENTAL",null,[13],"Procedure: Preoperative double-J ureteral stenting followed by retrograde intrarenal surgery",{"label":15,"type":16,"description":11,"interventionNames":17},"No-pre-stenting group","ACTIVE_COMPARATOR",[18],"Procedure: Direct retrograde intrarenal surgery without planned preoperative ureteral stenting",[20,25],{"type":21,"name":22,"description":23,"armGroupLabels":24,"otherNames":11},"PROCEDURE","Preoperative double-J ureteral stenting followed by retrograde intrarenal surgery","Participants randomized to this group will undergo insertion of a 4.8-6 French double-J ureteral stent approximately 7-14 days before definitive RIRS. The stent will be used to provide passive ureteral dilation. Definitive RIRS will then be performed using a miniaturized digital flexible ureteroscope and holmium:YAG laser lithotripsy.\n\nThe stent size, length, date of insertion, dwell time, technical success, complications, urinary tract infection, and stent-related symptoms will be recorded.",[9],{"type":21,"name":26,"description":27,"armGroupLabels":28,"otherNames":11},"Direct retrograde intrarenal surgery without planned preoperative ureteral stenting","Participants randomized to this group will undergo direct RIRS without planned preoperative ureteral stenting. No routine active ureteral dilation will be performed before initial access. Gentle dilation may be performed when clinically necessary and will be documented.\n\nIf safe access cannot be achieved, the procedure will be discontinued and a double-J ureteral stent will be inserted for passive dilation. Repeat RIRS will be scheduled approximately 7-14 days later.",[15],[30],{"name":31,"affiliation":32,"role":33},"Abul-fotouh Ahmed, MD","Department of Urology, Faculty of Medicine, Al-Azhar University, Cairo, Egypt","PRINCIPAL_INVESTIGATOR",[35],{"name":31,"role":36,"phone":37,"phoneExt":11,"email":38},"CONTACT","00201001066756","abulfotouhahmed@yahoo.com",[40],{"facility":41,"status":42,"city":43,"state":11,"zip":11,"country":44,"countryCode":45,"cosmosGeoPoint":46,"geoPoint":51,"contacts":52},"Department of Urology, Al-Hussein and Sayed Galal University Hospitals, Al-Azhar University","RECRUITING","Cairo","Egypt","EG",{"type":47,"coordinates":48},"Point",[49,50],31.24967,30.06263,{"lat":50,"lon":49},[53],{"name":54,"role":36,"phone":55,"phoneExt":11,"email":38},"Abul-fotouh Ahmed","+201001066756",{"type":33,"investigatorFullName":54,"investigatorTitle":57,"investigatorAffiliation":5,"oldNameTitle":11,"oldOrganization":11},"Principal Investigator","100652436","pre-stenting-in-miniaturized-rirs-100652436",false,"NCT07773090","Role of Pre-stenting Before Retrograde Intrarenal Surgery With Miniaturized Flexible Ureteroscopes","Does Pre-stenting Still Have a Role in Retrograde Intrarenal Surgery in the Era of Miniaturized Flexible Ureteroscopes? Surgical Outcomes From a Prospective Randomized Controlled Trial","Inclusion Criteria:\n\n* Participants must meet all of the following criteria:\n\n  * Adults aged 18-70 years.\n  * Unilateral renal calculi.\n  * Maximum total renal stone burden of 10-20 mm.\n  * Planned treatment with RIRS.\n  * Suitable candidate for elective endoscopic stone treatment.\n  * Negative or appropriately treated preoperative urine culture.\n  * Ability to provide written informed consent.\n  * Ability and willingness to comply with postoperative follow-up, including non-contrast CT at 4 weeks after the final RIRS procedure.\n\nExclusion Criteria:\n\n* Participants will be excluded for any of the following:\n\n  * Bilateral renal calculi requiring simultaneous surgical treatment.\n  * Active urinary tract infection, sepsis, or infected obstruction requiring urgent drainage.\n  * Solitary kidney when randomization is considered clinically unsafe.\n  * Known ureteral stricture or congenital ureteral abnormality likely to interfere with ureteroscopic access.\n  * Previous failed ipsilateral ureteroscopic access requiring clinically indicated pre-stenting.\n  * Existing ipsilateral ureteral stent or nephrostomy.\n  * Previous ureteral reconstruction or urinary diversion.\n  * Total renal stone burden greater than 20 mm.\n  * Staghorn calculi.\n  * Uncorrected coagulopathy.\n  * Pregnancy.\n  * Severe uncorrected cardiopulmonary disease precluding anesthesia.\n  * Inability or unwillingness to provide informed consent.\n  * Inability or unwillingness to comply with follow-up.\n  * Any other condition judged by the treating surgeon to make randomization or RIRS clinically inappropriate or unsafe.","ALL","18 Years","70 Years",{"count":69,"type":70},270,"ESTIMATED","INTERVENTIONAL",[73],"NA","This prospective randomized controlled trial will compare retrograde intrarenal surgery performed after routine preoperative ureteral stenting with direct retrograde intrarenal surgery without planned preoperative stenting in adults with unilateral renal calculi measuring 10-20 mm. The study will evaluate stone-free rate, ureteral access, need for rescue stenting, operative outcomes, complications, staged procedures, postoperative recovery, and auxiliary treatment.",[76],"Renal Calculi","2026-08-19",{"date":79,"type":80},"2026-08-21","ACTUAL",{"date":77,"type":80},{"date":83,"type":70},"2028-11-01",{"name":5,"class":6},1]