Indications and contraindications for shock wave lithotripsy and how to improve outcomes

Abstract

For over 35 years shock wave lithotripsy has proven to be an effective, safe and truly minimally invasive option for the treatment of nephrolithiasis. Various technical factors as well as patient selection can impact the success of the procedure. We used published work focusing on outcomes of shock wave lithotripsy, risk of complications, and strategies for improving stone fragmentation to create this review. Multiple patient and technical factors have been found to impact success of treatment. Skin to stone distance, stone density and composition, size and location of the stone within the urinary system all influence stone free rates. A slower rate with a gradual increasing voltage, precise targeting, proper coupling will improve stone fragmentation and decrease risk of complications. The selection of appropriate patients through a shared decision making process and attention to the technical factors that improve stone free rates is key to providing an effective treatment and patient satisfaction.

Automated Generation of Personalized Shock Wave Lithotripsy Protocols: Treatment Planning Using Deep Learning

“…Thus, the generated treatment sequence is enough to guide practice. The specifications of individual lithotripters limit the maximum number of shocks per session to 2000-4500 [4], and for the majority of treatments of upper ureteral and renal stones, the range is 2000-3500 [52]. We used 3000 as the upper limit in our implementation, which is a typical shock limit in renal stone treatment practices and can be adjusted according to shock wave generating machines.…”

“…Reported SWL stone-free rates approach 74%-88% [2,3]; however, it is not without risk. Common contraindications to SWL include pregnancy, coagulopathy or use of platelet aggregation inhibitors, aortic aneurysms, severe untreated hypertension, and untreated urinary tract infections [4]. Failure of SWL treatment results in unnecessary exposure to various complications, such as loin pain, dysuria, analgesia, hematuria, and infection [3,5].…”

“…Given such risks, previous studies have identified proper patient selection, modifications in treatment technique, and employment of adjunctive measures as elements to improve SWL outcomes [6]. The treatment outcomes are strongly affected by a variety of preoperative patient characteristics (PPC), including BMI [7][8][9], stone location, overall stone burden [4], skin-to-stone distance [10,11], stone composition [12,13], stone density [14][15][16][17], and variation coefficients of stone density [18]. Various studies have also demonstrated that precise targeting [19,20] and tight coupling [21,22] increase fragmentation probability.…”

Shockwave lithotripsy for urolithiasis: a 12-month analysis of referral data to a metropolitan Australian Hospital

“…In deciding appropriate treatment it is important to consider the size and density of the stone on imaging, the anatomical complexity including location of the stone, the presence of renal artery or abdominal aortic aneurysms, and whether a female could be pregnant. 5 It is important to identify whether a patient is suitable for SWL early to facilitate prompt management.…”

Medical and surgical management of urolithiasis

“…In many countries throughout the world shock wave lithotripsy had been documented to be in decline with a parallel increase in retrograde ureteroscopic approaches to both ureteral and renal stones. Kenneth T. Pace and his colleagues [6] from the University of Toronto provide an excellent update on the current role of shock wave lithotripsy in stone treatment and how to select the best patients for this form of therapy and to optimize results. Olivier Traxer and his colleagues [7] from Tenon Hospital in Paris have contributed as much as any urologic surgeon worldwide in pushing the limits for ureteroscopic treatment and provide an excellent state-of-the-art update on retrograde ureteroscopy for stone management.…”