From the Guidelines
The second shockwave lithotripsy (SWL) treatment to the same kidney can be safely considered after re-evaluating the stone characteristics and patient characteristics that may have contributed to the initial failure, and it is recommended to offer endoscopic therapy as the next treatment option if initial SWL fails 1. When considering a second shockwave treatment, it is crucial to assess the outcomes of the initial treatment, including the degree of stone fragmentation and clearance.
- Patients who have had partial fragmentation and clearance may be considered for repeat SWL,
- while those with no fragmentation and/or clearance may be selected specifically for endoscopic intervention, such as percutaneous nephrolithotomy (PCNL) or ureteroscopic removal (URS), which have reported success rates of 86-100% and 62-100%, respectively 1. The decision to proceed with a second SWL treatment should be based on a thorough evaluation of the patient's overall condition, including any potential risks or complications associated with repeated shockwave therapy.
- Factors such as stone size, location, density, and composition, as well as patient characteristics like obesity and collecting system anatomy, should be carefully considered 1. In general, it is essential to prioritize the patient's safety and well-being, and to choose the treatment option that is most likely to achieve the best outcomes in terms of morbidity, mortality, and quality of life.
- This may involve a multidisciplinary approach, incorporating the expertise of urologists, radiologists, and other healthcare professionals to determine the most appropriate course of treatment 1.
From the Research
Ideal Interval for Repeated Shockwave Lithotripsy Sessions
- The ideal interval between repeated extracorporeal shockwave lithotripsy (SWL) sessions for renal stones is a crucial factor in ensuring the safety and effectiveness of the treatment 2.
- A study published in the Journal of Endourology found that an interval of 7 days is required between SWL sessions to allow for complete recovery of kidney functions 2.
- The study compared the outcomes of patients who underwent second SWL sessions after 3,7, and 14 days and found that the 7-day interval group had the best treatment success rate and the least amount of kidney damage 2.
Factors Influencing Treatment Outcome
- Several factors can influence the outcome of shockwave lithotripsy, including stone size, location, and composition, as well as patient characteristics such as skin-to-stone distance and overall health 3, 4, 5.
- A study published in the Asian Journal of Urology found that a slower rate with a gradual increasing voltage, precise targeting, and proper coupling can improve stone fragmentation and decrease the risk of complications 3.
- Another study published in Urology found that the number of stones, previous treatment, and maximum kilovoltage setting of ESWL at treatment were significant variables that influenced treatment outcome 4.
Safety and Efficacy of Shockwave Lithotripsy
- Shockwave lithotripsy is a safe and effective treatment for renal stones, with a low risk of complications and a high stone-free rate 3, 5.
- A study published in Urologia Internationalis found that ESWL is a safe and efficient first-line therapy for treatment of isolated small lower pole kidney stones, with acceptable stone-free rates, low morbidity, and few complications 5.
- However, more research is needed to establish the efficacy of low-intensity shockwave therapy for treating renal diseases, although it has shown promise in animal models 6.