From the Guidelines
The patient with a large obstructive calculus of 17x12 mm in the right proximal ureter is not a good candidate for Extracorporeal Shock Wave Lithotripsy (ESWL) as the first line of treatment due to the size of the stone. According to the American Urological Association/Endourological Society guideline, part II 1, for symptomatic patients with a total renal stone burden >20 mm, clinicians should offer Percutaneous Nephrolithotomy (PCNL) as first-line therapy. Although the stone is located in the proximal ureter and not in the kidney, its size exceeds the recommended threshold for ESWL.
The guideline suggests that PCNL offers a higher stone-free rate than ESWL or Ureteroscopy (URS) and is less invasive than open surgery or laparoscopic/robotic-assisted procedures 1. Furthermore, the success rate of PCNL is less dependent on stone composition, density, and location.
Some key points to consider in the management of this patient include:
- The size and location of the stone: 17x12 mm in the right proximal ureter
- The patient's symptoms and overall health status
- The potential risks and benefits of each treatment option, including ESWL, URS, and PCNL
- The importance of proper patient selection for each treatment modality to maximize stone-free rates and minimize complications
In this case, given the size of the stone, PCNL is the recommended treatment approach. However, the decision should be individualized based on the patient's specific circumstances, and a thorough discussion of the risks and benefits of each option should be undertaken with the patient. The American College of Radiology also emphasizes the importance of stone size and location in determining the need for invasive management 1.
From the Research
Stone Size and Location
- The size of the obstructive calculus is 17x12 mm, which is a significant factor in determining the best management approach 2.
- The location of the stone is in the right proximal ureter, opposite to the L4 level, which may affect the treatment outcome 2, 3.
Treatment Options
- Extracorporeal Shock Wave Lithotripsy (ESWL) is a common treatment option for kidney stones, but its success rate depends on multiple factors, including stone size, density, and location 2, 3, 4, 5.
- For stones larger than 10mm, alpha-blockers such as tamsulosin may be useful in improving treatment outcomes 5.
- Percutaneous nephrolithotomy (PCNL) or retrograde intrarenal surgery (RIRS) may be considered as alternative treatment options, especially for larger stones or those with higher density 3, 6.
ESWL Success Rate
- The success rate of ESWL decreases with increasing stone size, and stones larger than 20mm may have a lower success rate 2, 3.
- The location of the stone in the proximal ureter may also affect the success rate of ESWL, with lower success rates reported for stones in the lower calyceal area 2.
- However, ESWL may still be a viable option for stones in the proximal ureter, especially if the stone is not too large or dense 4, 5.
Complications and Considerations
- ESWL is generally a safe procedure, but minor complications may occur, such as pain, bleeding, or infection 5.
- Patient-related factors, such as hypertension, diabetes, or impaired renal function, may increase the risk of complications or adverse effects 4.
- The decision to use ESWL or alternative treatment options should be made on a case-by-case basis, taking into account the individual patient's characteristics and medical history 3, 4, 5.