Clinical Research Directory

Ureteral Stenting After Retrograde Intrarenal Surgery for Renal Stones

Several studies evaluated the benefit of a short-term external ureteral catheter (UC) compared to double-J (DJ) ureteral stent after flexible ureteroscopy (URS); the results were controversial. These studies had combined analyses of ureteral and renal stones with a high risk of selection bias. Studies comparing external UC and DJ stent after flexible URS for isolated renal stones are lacking. In the present study, the investigators will compare the outcomes of using a one-day external UC versus a DJ internal ureteral stent for ureteral drainage after retrograde flexible URS (retrograde intrarenal surgery "RIRS") for renal stones. The investigators aim to identify the best ureteral drainage method after RIRS regarding stone clearance, complications, and stent-related symptoms.

Long-term Safety of UAS-assisted vs Sheathless RIRS in Non-prestented Patients

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/progressive ipsilateral hydronephrosis and other safety and efficacy outcomes. Propensity-score methods and adjusted regression analyses will be used to control confounding.

Mini-PNL, RIRS, and ESWL for Treatment of Medium-Sized, High-Density, Non-Lower Pole, Renal Stones

The optimal management of medium-sized renal stones remains quite challenging and continues to be contested. In the present study, the investigators will compare mini-PNL, RIRS and SWL in the treatment of non- lower pole, medium size, high dense renal stones regarding the stone-free rate, the safety of the procedures, cost, and patients' and surgeon's satisfaction. Eligible patients will be randomly allocated into three equal groups (mini-PNL, RIRS, and SWL). Postoperative, patients will be followed-up by regularly for 3 months. The study parameters will be compared between groups.

Safety and Efficacy of Fluoroscopy-free Technique During Retrograde Intrarenal Surgery for Renal Stones

Aiming to reduce radiation exposure to patients and physicians, the investigators conduct this study protocol to evaluate the possibility of performing retrograde intrarenal surgery (RIRS) under direct visualization without fluoroscopy. the investigators will prospectively evaluate the outcome of fluoroscopy-free RIRS for renal stones in comparison with the standard technique. The investigators expected that the fluoroscopy-free technique has high safety and efficacy even in complicated cases.

General Versus Spinal Anesthesia in RIRS

The impact of anesthesia type on Retrograde Intrarenal Surgery (RIRS) outcomes remains a subject of ongoing debate. Several studies have compared general anesthesia (GA) and spinal anesthesia (SA) in endourological procedures, with conflicting results regarding operative time, complication rates, and stone-free outcomes. Importantly, the interaction between anesthesia type and stone characteristics-particularly stone size-has not been fully elucidated. Therefore, this study aims to conduct a retrospective comparative analysis of general versus spinal anesthesia in patients undergoing RIRS at Qena University Hospital, with particular emphasis on the effect of stone size stratification on perioperative outcomes.

Effects of Education Given to RIRS With Mobile Application on Anxiety, Fear of Surgery, Pain, Analgesic Consumption, Length of Hospital Stay, Complication Development, Readmission and Hospitalization

The aim of this study was to determine the effect of the education to be given with a mobile application to be developed for RIRC patients on preoperative anxiety, fear of surgery, postoperative pain level, analgesic consumption, length of hospital stay, development of complications in the first month, readmission and number of hospitalizations. The study was planned as a prospective, two-arm (1:1), randomized controlled trial. The study will be conducted with 68 patients in the urology clinic of a university hospital. Patients will be randomly assigned to the control group and the mobile application training group.. Descriptive Information Form, Visual Analog Scale (VAS), Analgesic Consumption Monitoring Form, State Anxiety Scale, Surgical Fear Scale and Patient Monitoring Form will be used to collect the data. "Introductory Information Form", 'State Anxiety Scale', and 'Surgical Fear Scale' will be applied to all patients before surgical intervention. "State Anxiety Scale" and 'Surgical Fear Scale' will be administered both before and at the end of the trainings in the preoperative period. Trainings and preoperative scales to be completed will be carried out when the patient is admitted to the clinic for surgery. The group to be trained with the mobile application will be introduced to the application and the application will be downloaded to their phones, tablets or computers. Then, the questions of the patients regarding the mobile application will be answered. Patients in the control group will receive routine information in the clinic. After the surgical intervention, "VAS" and "Analgesic Consumption Monitoring Form" will be applied to all patients. The pain of the patients will be evaluated with VAS when they come to the postoperative room, at the 6th postoperative hour and at the 12th postoperative hour. The amount of analgesia consumed by the patients within 24 hours postoperatively will be recorded in the Analgesia Consumption Form. The duration of hospital stay will be recorded on the "Patient Follow-up Form" on the day of discharge. Patients who underwent RIRC will be called by the investigators one month later and their complication development status, hospitalization/ rehospitalization status will be learned and recorded in the "Patient Follow-up Form".

Tamsulosin and Intraureteral Aminophylline for Ureteral Access During RIRS

This multicenter randomized controlled trial will evaluate whether preoperative tamsulosin, intraureteral aminophylline, or their combination can improve ureteral access during primary retrograde intrarenal surgery for renal stones. Adult patients with unilateral renal stones measuring 2 cm or less and planned placement of a 10/12 Fr ureteral access sheath will be randomly assigned to one of four groups in a 2x2 factorial design. Participants will receive either tamsulosin or placebo for 7 days before surgery and either intraureteral aminophylline or intraureteral placebo during the procedure. The main outcome will be successful first-attempt placement of the planned 10/12 Fr ureteral access sheath after study solution instillation, without active ureteral dilatation, sheath downsizing, prestenting with deferred surgery, or abandonment of the procedure due to access failure.

Homework in Retrograde Intrarenal Surgery

To evaluate the effectiveness of this homework on stone clearance rates after retrograde intrarenal surgery (RIRS) by instructing the patient in the home environment and suggesting percussion and movement/position changes to assist in spontaneous stone passage.

Retrograde Intrarenal Surgery Low Risk Trial

In the treatment of kidney stones and upper ureteral stones, flexible ureteroscopic lithotripsy has become the mainstream choice due to its minimally invasive nature and high safety. However, there is still no universal consensus on the use of prophylactic antibiotics before surgery. Taiwan, located in the subtropical region, is one of the areas in the world with a high incidence of urinary tract stones. Currently, there are no established guidelines for the use of prophylactic antibiotics before flexible ureteroscopic lithotripsy in Taiwan. This study aims to evaluate the differences between single-dose, different types of prophylactic antibiotics in generally healthy adult patients undergoing flexible ureteroscopic lithotripsy.