Shock wave lithotripsy for clinically necessary ureteral stones (indications and contraindications)

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In February 1980, shock wave lithotripsy was first applied to the treatment of kidney stones, and it was only applied to the upper ureteral calculi after half a year; the middle ureteral calculi were once considered "unowned"; the lower ureteral calculi were initially taboo
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It wasn't until the mid-1980s that shock wave lithotripsy was gradually applied to the treatment of middle and lower ureteral stones.
To this day, it is still the first-line treatment for ureteral stones
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In SWL (extracorporeal shock wave lithotripsy), the ureteral segmentation adopts the urological segmentation standard
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The preoperative preparation, posture and impact method of each segment of the ureter are different
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Indications and contraindications can be treated with SWL throughout the entire course of ureteral stones
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The best indication is that the diameter of the stone is ≤ 1.
0cm, and the kidney function is good
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In 2017, the EUA guidelines group applied a systematic review method to evaluate the pros and cons of SWL and URS (ureteroscopic lithotripsy).
The results showed that compared with SWL, the four-week stone-free rate of URS increased significantly, but within 3 months, the two There was little difference in the stone-free rate between the groups
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URS has a lower chance of retreatment and requires lower adjuvant treatment, but it has higher requirements for adjuvant treatment, more complications, and longer hospital stay
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Compared with URS, SWL has fewer complications (Table 1)
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In addition, from the perspective of price-efficiency ratio, domestic SWL costs are only 1/20~1/10 of URS.
Whether it is social security system or personal payment, SWL should be considered first
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Table 1 Comparison of efficacy and complications between SWL and URL for upper ureteral stones with a diameter greater than 10mm (click to enlarge) The contraindications of ureteral stones SWL are the same as those for kidney stones
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What needs attention is whether the distal end of ureteral stones is unobstructed and the degree of stone incarceration
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In addition, because the ureter is adjacent to the abdominal aorta and iliac artery, patients over 50 years of age need to pay attention to whether there is an aneurysm in the shock wave conduction path
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 Shock waves can cause ureteral muscular and serous edema, vacuolization of muscle cells, swelling of mitochondria, and destruction of mitochondrial cristae
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In clinical treatment, it was also found that in some patients who switched to open surgery after repeated shocks failed, the ureteral wall had already undergone fibrosis or even scarring, and the surrounding adhesions were serious
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In principle, it is recommended that the SWL interval for ureteral stones in the same site be more than one to two weeks, and the stones can be moved to a new site to re-shock within one day
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This article is an excerpt from "The Principle and Application of Shock Wave Lithotripsy" (China Science and Technology Press)
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