Comparison of Extracorporeal Shock Wave Lithotripsy and Percutaneous Nephrolithotomy for the Treatment of Renal Calculi in Lower Pole Calices

Abstract

Lower pole caliceal calculi can be treated by percutaneous nephrolithotomy (PCNL) or by extracorporeal shock wave lithotripsy (ESWL). In previous studies, investigators have noted that stones in lower calices treated with ESWL have a poor clearance rate. This study compared PCNL and ESWL treatments for solitary lower caliceal stones. Thirty-five patients with lower pole caliceal stones were treated with ESWL (Dornier HM3), and 29 patients were treated with PCNL between March 1983 and January 1988. Pretreatment intravenous urograms of the ESWL patients were examined, and the length and width of the lower pole infundibulum were recorded. The mean stone diameter was 9 mm (range 3 to 30 mm) in the ESWL group and 10 mm (range 4 to 27 mm) in the PCNL group. All patients in the ESWL group had adequate stone fragmentation (particles <4 mm). Stone composition was similar for the two groups. A plain film was obtained at a median follow-up of 13 months in 94% of the ESWL patients and 90% of the PCNL patients. There was a 59% stone-free rate for the ESWL group and an 85% stone-free rate for the PCNL group. The ESWL stone-free rate did not correlate with infundibular width or length. The ESWL patients spent 2.5 days in the hospital ν 6.1 days for the PCNL patients. The PCNL patients had a two-fold greater recovery time (19.3 days ν 10 days). Interestingly, there was no difference between the two treatment groups in regard to recurrent stone disease: 10% of ESWL patients had a recurrence within 18 months, and 11% of the PCNL patients had a recurrence within 22 months after treatment. PCNL for caliceal stones is more invasive, has a higher morbidity, and is