Relation of Initial Radiographic Findings to Outcome and Treatment of Staghorn Calculi

Abstract

In a 3-year period, 78 patients with staghorn calculi were treated by either percutaneous nephrolithotomy (PCNL) (N = 8), extracorporeal piezoelectric lithotripsy (EPL) (N = 18), or a combination of these modalities (N = 52). The latter group consisted of those who were originally selected for an attempt at monotherapy with EPL but required PCNL as part of their management (N = 22) -and those who had initial debulking of their calculi and subsequent EPL (N = 30). Overall, 46 (59%) of the patients were rendered stone free, and a further 11 (14%) had small (<4 mm) residual fragments. Of those selected for PCNL initially, 30 of 38 (79%) were stone free or had only small fragments, compared with 27 of 40 (67%) who began with EPL. The combination of initial PCNL and subsequent EPL as necessary provided the best results with the fewest complications. The radiographic density of the stone correlated well with rate of fragmentation on EPL, with the results suggesting that EPL monotherapy should be avoided for patients with calculi denser than the 12th rib. Total stone area provided little extra information in the initial assessment of large complex stones, but it was a more sensitive indicator of the bulk of residual fragments. Stones with detached caliceal segments were most successfully treated by EPL only after initial percutaneous debulking of the major pelvic component(s). We therefore believe that the selection of patients for EPL monotherapy is most satisfactory based on the density of the calculus and the anatomic drainage of that kidney rather than on stone bulk.