Event rates for Residual Fragments • URS • PNL • SWL >4mm 59% after 1.4 yrs Chew 2016 <4mm 28% after 1.4 yrs Chew 2016 <4mm 26% after 2.3 yrs 73% at 5 years Altunrede 2011 Olvera‐Posada 2016 21‐59% after 5 yrs Khaitan 2002, Osman2005