WHEN SHOULD ONE PERFORM SHOCKWAVE LITHOTRIPSY FOR LOWER CALICEAL STONES

Extracorporal shockwave lithotripsy of lower caliceal stones is often unrewarding because of the difficulty of passing stone fragments. We r eport our results in SWL of lower pole stones in 219 patients and comp are them with the results of SWL of middle (82 patients) and upper pol e (85 patients) stones. The stone-free rate of SWL monotherapy was fou nd to be 59%, 77%, and 64% in lower, middle, and upper caliceal stones , respectively. In lower pole stones, SWL was unsuccessful in 41% of t he patients, of whom 9% had minimal residual asymptomatic stones (less than 4 mm in greatest diameter). In comparison with the results of pe rcutaneous nephrolithotomy (PCN) of lower pole urolithiasis in the lit erature, SWL was unsuccessful in large stones, with stone-free rates o f 13% and 0 when the stone size was 3 to 4.9 cm(2) and >5 cm(2), respe ctively. A stone-free rate of 82% when the stone burden was <1 cm(2) i s similar to the PCN results of other centers, suggesting that SWL may be the first choice of treatment in lower pole stones of this size. W e achieved a stone-free rate of 59% when the stone size was between 1 and 3 cm(2), which is lower than the stone-free rates of PCN in the li terature. In spite of its lower stone-free rates, SWL, with its lower morbidity, may still be considered an acceptable treatment modality in this range of moderate stone burden, especially when there is a patie nt desire for conservative treatment.