Is a 6 mm calculus in the left ureter, causing mild hydroureter and hydronephrosis, indicated for complex ureteroscopy (Ureteroscopy)?

Management of 6 mm Left Ureteral Calculus with Mild Hydroureter and Hydronephrosis

Ureteroscopy is indicated for a 6 mm calculus in the left ureter at L3 level causing mild hydroureter and hydronephrosis, as it offers high stone-free rates with minimal complications. 1

Treatment Options for Ureteral Stones

The management of ureteral stones depends on several factors:

1. Stone size and location
2. Presence of obstruction
3. Stone composition (density)
4. Patient factors

Ureteroscopy (URS)

For a 6 mm stone in the ureter causing hydronephrosis, ureteroscopy is highly effective with several advantages:

• High stone-free rates (81-94%) depending on stone location 1
• Single procedure success is typically higher for URS (87.8%) compared to SWL (60.4%) for intermediate-sized stones 2
• Minimal complications with modern techniques (ureteral perforation rates <5%, stricture formation ≤2%) 1
• Effective for high-density stones (1568 HU in this case indicates a very dense stone)

Shock Wave Lithotripsy (SWL)

While SWL is an alternative treatment option:

• Lower single-treatment success rates (60.4%) compared to URS (87.8%) for intermediate-sized stones 2
• Higher need for auxiliary treatments (42.3% after SWL vs. lower rates with URS) 2
• Less effective for high-density stones (>1000 HU), which is relevant for this 1568 HU stone
• Advantage of minimal anesthesia requirements compared to URS 1

Why Ureteroscopy is Preferred for This Case

1. Stone size (6 mm): While stones <5 mm may pass spontaneously, a 6 mm stone in the ureter with evidence of obstruction (hydronephrosis) typically requires intervention

2. Stone density (1568 HU): Very high-density stones respond better to direct fragmentation with laser lithotripsy during URS than to SWL

3. Presence of hydroureter and hydronephrosis: These findings indicate obstruction that should be promptly relieved to prevent further renal damage 3

4. Location at L3 level: Mid-ureteral stones are accessible with modern flexible ureteroscopes, with stone-free rates of approximately 86% 1

Procedural Considerations

• Preoperative urine culture is recommended to rule out infection
• Antibiotic prophylaxis is recommended for the procedure 4
• Holmium:YAG laser lithotripsy is typically used during URS for effective stone fragmentation
• Ureteral stent placement may be considered after the procedure, though routine stenting is not always necessary

Potential Complications to Monitor

• Ureteral injury (occurs in <5% of cases with modern techniques) 1
• Stricture formation (≤2% with current techniques) 1
• Infection (can be minimized with appropriate antibiotic prophylaxis)
• Residual fragments (less common with URS compared to SWL)

Follow-up Recommendations

• Imaging (ultrasound or KUB radiography) to confirm stone clearance
• Metabolic evaluation to identify underlying causes and prevent recurrence
• Increased fluid intake (>2L/day) to help prevent recurrent stones 4

In conclusion, for a 6 mm high-density ureteral calculus causing mild hydroureter and hydronephrosis, ureteroscopy offers the highest likelihood of stone clearance in a single procedure with acceptable complication rates.