Semi-rigid Ureteroscopy Versus Flexible Ureteroscopy For the Treatment of Proximal Ureteric Stone

A Randomized Controlled Trial Comparing Semi-rigid Ureteroscopy and Flexible Ureteroscopy For the Treatment of Proximal Ureteric Stone

The present study is randomized in nature, comparing the stone free rate and complications rate between semi-rigid ureteroscopy (SR-URS) and Flexible Ureteroscopy (F-URS) for the treatment of Proximal Ureteric stone (PUS), whereby the preoperative assessments, procedure and reporting of outcomes will all be standardized.

There are various treatment options that can be used for the treatment of PUS, which include extracorporeal shockwave lithotripsy (SWL), ureteroscopy (URS), percutaneous nephrolithotomy (PCNL), antegrade uretero-lithotripsy, laparoscopy, and rarely, open surgical procedures. However, the standard, and the most frequently used modalities are SWL and ureteroscopy. When comparing the effectiveness in the treatment of Proximal Ureteric stone (PUS) between SWL and URS, SWL has lower rates of complication and morbidity, but URS has a higher likelihood of successfully treating the patient within a single procedure. Additionally, with the advancements in technology and miniaturization of the ureteroscopes, along with the presence of auxiliary instruments such as holmium laser and retrieval baskets, ureteroscopy is more widely used. In the proximal ureter, SR-URS tends to encounter difficulties in accessing the stone, but F-URS aids in overcoming those difficulties. As a result, the use of F-URS for PUS has indicated a strong success rate with lower likelihood of complications. When comparing the drawbacks of the two types of modalities, F-URS tends to be more expensive, and requires auxiliary instruments. And SR-URS tends to have lower success rate along with an increased rate in complications. The precedence of FURS over SR-URS in the treatment of PUS is yet to be extensively studied. Presently there are only five studies that have compared the two modalities of treatment. But, due to the lack standardization of variables, procedure, follow-up imaging and reporting of outcomes in the past studies, it is imperative to conduct study that is prospective and randomized in nature. The present study is randomized in nature, comparing the stone free rate and complications rate between SR-URS and F-URS for the treatment of PUS, whereby the preoperative assessments, procedure and reporting of outcomes will all be standardized.

Patient with upper ureteric stone who are randomized in this arm will undergo semi-rigid ureteroscopy for treatment of the stone.

Patient with upper ureteric stone who are randomized in this arm will undergo flexible ureteroscopy for treatment of the stone.

Flexible ureteroscopy is the use of flexible ureteroscope for the treatment of stone in the upper ureter with the aid of laser lithotripsy.

Semi-rigid ureteroscopy is the use of the semi-rigid ureteroscope for the treatment of stone in the upper ureter with the aid of laser lithotripsy.

Sone free status will be assessed by doing CT KUB scan 4 weeks postoperative and it is defined as patients with no residual stones or clinically insignificant residual fragments (< 2 mm).

To evaluate the complication rate post procedure including infection rate, genitourinary injury, hematuria, emergency visits rate and we will use of modified Calvin Dindo classification to grade the surgical complications.

To compare stone free rate and complications between patients with ureteric stent and patients without ureteric stent

Patients will be stratified into two groups: group 1 with ureteric stents and group 2 without ureteric stents. Then comparison between the two groups in regards the stone free rate and the complications rate as per the previous definitions.

Inclusion Criteria: Age ≥ 18 years Single proximal ureteric stone indicated for active treatment with ureteroscopy (stented or non-stented) Exclusion Criteria: Solitary Kidney Bilateral ureteric stones Ipsilateral multiple simultaneous ureteric stones Ipsilateral kidney stone Active UTI Coagulopathy diseases Ipsilateral ureteral anomalies, ureteral disorder (tumor or stricture) or previous ureteral open surgery. Pregnant patients. Unable to give informed consent. Patient is not agreeing to go through the randomization.

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