From the Guidelines
A right-sided vesicoureteric junction stone measuring 6 x 4 mm causing mild hydroureteronephrosis is typically indicated for ureteroscopy, as this procedure has high stone-free rates and low complication rates for stones in all locations in the ureter, including the proximal ureter 1. The stone's location at the vesicoureteric junction, where the ureter meets the bladder, and its size of 6 x 4 mm, make it a good candidate for ureteroscopy, as stones smaller than 5 mm may pass spontaneously, but this stone is at a location where stones often become impacted. Some key points to consider in this case include:
- Ureteroscopy has evolved into a safer and more efficacious modality for treatment of stones in all locations in the ureter, with overall stone-free rates remarkably high at 81% to 94% depending on stone location 1.
- The development of smaller caliber semirigid and flexible ureteroscopes and the introduction of improved instrumentation, including the holmium:YAG laser, have reduced complication rates, most notably ureteral perforation rates, to less than 5% 1.
- Long-term complications such as stricture formation occur with an incidence of 2% or less 1.
- The flexible ureteroscope is largely responsible for improved access to the proximal ureter, with superior stone-free rates achieved using flexible URS (87%) compared with rigid or semirigid URS (77%) 1. The procedure typically takes 30-90 minutes under general anesthesia, with patients often discharged the same day, and a ureteral stent may be placed temporarily afterward to ensure proper drainage and healing. Alternative approaches like shock wave lithotripsy might be less effective for stones at this location, making ureteroscopy the preferred option to relieve the obstruction and prevent further kidney damage from prolonged hydroureteronephrosis.
From the Research
Indications for Ureteroscopy
- The patient has a right-sided vesicoureteric junction stone measuring about 6 x 4 mm, which is causing mild right-sided hydroureteronephrosis.
- Ureteroscopy is a minimally invasive procedure that can be used to treat stones in the urinary tract, including those at the vesicoureteric junction 2.
- The size of the stone (6 x 4 mm) is relatively small, and ureteroscopy may be an effective treatment option for stones of this size 3.
Comparison with Other Treatment Options
- Extracorporeal shock wave lithotripsy (ESWL) is another treatment option for kidney stones, but its effectiveness may be lower for stones at the vesicoureteric junction 2.
- ESWL may not be as effective for stones in the lower pole of the kidney, and ureteroscopy may be a better option for these cases 3.
- Percutaneous nephrolithotomy (PCNL) is a more invasive procedure that may be used for larger stones, but it may not be necessary for smaller stones like the one in this case 2.
Potential Complications and Considerations
- Retrograde migration of the stone is a potential complication of ureteroscopy, and it is important to consider this risk when deciding on a treatment plan 4.
- The use of noncontrast limited pelvic CT scans may not always detect retrograde stone migration, and full upper renal tract imaging may be necessary to evaluate the stone's position 4.
- Even small stones can cause significant symptoms and complications, such as rupture of the pelvicoureteric junction, and prompt treatment may be necessary to prevent these complications 5.