M. Nouri et al., Predictive factors of the success of EDAP LTO2 (R) extracorporeal shock-wave lithotripsy of lower caliceal stones, PROG UROL, 10(4), 2000, pp. 529-536
Objective: to determine the predictive factors of success of extracorporeal
shock-wave lithotripsy (ESWL) for lower caliceal stones.
Patients and Methods: The case files of 100 patients with a single stone in
the lower pole of the kidney, ranging in size from 6 to 25 mm, treated by
EDAP LTO2 extracorporeal lithotripsy between 1994 and 1997 were studied Pre
treatment intravenous urography was reviewed to assess the characteristics
of the stone, to measure the pyelocaliceal angle and to study the anatomy o
f the lower pole of the kidney.
Results: The overall stone-free rate at 3 months was 57%. The success rate
was 67.18% for stones smaller them 1 cm and 38.88% for stones larger than 1
cm. Stones denser than bone rc ere successfully treated in 45.5% of cases,
those less dense than bone were successfully treated in 71.11% of cases. T
he success rate was 86.04% when the pyelocaliceal angle was greater than 90
degrees and 35.08% when this angle was less than 90 degrees. The stone-fre
e rate was 75% when the caliceal stalk was less than 3 cm and 37.5% when th
e stalk was greater than 3 cm.
Conclusion: In this series, the size of the stone, ifs density the pyelocal
iceal angle and the length of the caliceal stalk were predictive elements o
f the success of ESWL for lower caliceal stones. The pyelocaliceal angle wa
s the most significant factor A very dense stone on the plain abdominal fil
m with a diameter of 1 cm or more and presenting unfavourable anatomical fa
ctors should be treated by percutaneous nephrolithotomy as the first-line p
rocedure.