What is the next step in managing a 40-year-old man with an impacted ureteral stone after semi-rigid ureteroscopy (URS), where a guidewire is placed beyond the stone and the ureteroscope is passed up to the stone level without visualizing it?

From the Guidelines

The next step in managing this 40-year-old man with an impacted ureteral stone after semi-rigid ureteroscopy should be to place an indwelling ureteral stent over the guidewire. This approach is based on the principle of minimizing complications and ensuring the patient's safety, as indicated by the 2007 guideline for the management of ureteral calculi 1. The guidewire is already in place beyond the stone, and the ureteroscope has been passed up to the stone level, but the stone is not visualized, suggesting that there may be ureteral edema or narrowing that needs to be addressed. Placing an indwelling ureteral stent can help to ensure ureteral patency and prevent obstruction, especially since the stone is impacted and may cause further narrowing or edema. Some key points to consider in this scenario include:

• The patient has an impacted ureteral stone, which can cause ureteral edema and narrowing, making direct visualization and fragmentation challenging.
• The guidewire is already in place beyond the stone, which provides a safe pathway for stent placement.
• The ureteroscope has been passed up to the stone level, but the stone is not visualized, suggesting that there may be a need for further intervention to address the impacted stone.
• Placement of a ureteral stent is a common approach in such cases, as it can help to ensure ureteral patency and prevent complications, as noted in the 2007 guideline for the management of ureteral calculi 1. Alternatively, other options such as balloon dilation of the ureter or holmium laser incision of tissue covering the stone could be considered, but these approaches may carry additional risks and complications, and may not be necessary if stent placement is successful. Percutaneous antegrade ureteral stenting may also be considered if retrograde stent placement is unsuccessful, as noted in the 2020 ACR Appropriateness Criteria for radiologic management of urinary tract obstruction 1. However, this approach should be reserved for cases where other options have failed, due to the potential risks and complications associated with percutaneous procedures.

From the Research

Next Steps in Managing Impacted Ureteral Stone

Given the scenario where a guidewire is manipulated beyond the stone and forms a tight curl at the level of the UPJ, and the ureteroscope is passed up to and above the level of the stone without visualizing it, the next steps can be considered based on available evidence:

• Placement of Indwelling Ureteral Stent: The use of a guidewire to facilitate the placement of an indwelling ureteral stent is a common technique in managing ureteral obstructions 2, 3, 4. This approach can provide internal urinary diversion when retrograde placement is challenging.
• Techniques for Stent Placement: Studies have outlined various techniques for cystoscopic ureteral stent placement, including the use of fluoroscopy to guide the stent into the renal pelvis 3. The placement of a stent can help in managing the obstruction caused by the impacted stone.
• Considerations for Ureteral Stents: When considering the placement of a ureteral stent, factors such as stent composition, design, and potential complications like encrustation and microbial colonization should be taken into account 5. The choice of stent should be based on the specific clinical situation and the characteristics of the available stents.
• Alternative Approaches: While the primary focus is on less invasive techniques like stent placement, other approaches such as balloon dilation of the ureter or the use of specific types of stents like the Resonance metallic ureteral stent may be considered based on the patient's condition and the availability of resources 6.

Potential Options

Based on the provided scenario and evidence:

• B. Place indwelling ureteral stent over the guidewire appears to be a viable next step, considering the guidewire is already in place beyond the stone.
• Other options like A. Balloon dilation of ureter, C. Holmium laser incision of tissue covering stone, D. PCN and antegrade stent placement, and E. Open surgical exploration may be considered based on further evaluation of the stone's position, the patient's condition, and the expertise available.