[Percutaneous treatment of calculi in the horseshoe kidney].
Horseshoe kidney and renal anomalies are not a contraindication for endourological procedures. In horseshoe kidney, anatomical features and impaired drainage of urine, make stone treatment by ESWL technically difficult and fragments output unsuccessfully. By PNL, via a middle or upper calix posterior approach, is possible to remove the stone without serious complications. Technical modifications of traditional percutaneous approach are required to deal with these cases. A careful preoperative study of caliceal and pelvic anatomy by retrograde pyelography with films taken in lateral and oblique position is needed to plan the correct approach to the stone. However, a skilled use of endourological procedures and techniques are required. Authors present our experience on two cases successfully treated.