Update on technological and selection factors influencing shockwave lithotripsy of renal stones in adults and children

Purpose of Review: The aim of this review is to evaluate recently published peer reviewed literature on the subject of shockwave lithotripsy. Recent Findings: Based on in-vitro animal studies, escalating voltage results in better stone comminution and ultimately applies less total voltage to the surrounding tissue, theoretically causing less harm. Several studies have also shown that a slower shockwave rate improves stone fragmentation for intrarenal stones. Stones measuring greater than 1000 HU require a significantly greater number of shocks to destroy. The current literature continues to support shockwave lithotripsy as both a safe and effective means for managing stone disease in pediatric patients. Medical expulsive therapy with alpha-blockers appears to be efficacious, shortening the time to stone and fragment expulsion as well as minimizing pain. Skin-to-stone distance, Hounsfield units, stone size, and location are the best studied and most validated parameters that correlate with shockwave lithotripsy success. Summary: Shockwave lithotripsy continues to evolve with the advent of better technology, improved imaging, and the development of several parameters that can be used to predict success, to counsel our patients, and improve stone-free rates.