THE DILEMMA OF THE CROSSING VESSEL AT THE URETEROPELVIC JUNCTION - PRECISE ANATOMIC STUDY

To maximize the success rate of endopyelotomy with minimal risk of com plications, some debate still persists on the technique of incising th e ureteropelvic junction (UPJ), patient selection, and prognostic fact ors. Also, some controversy exists concerning the vascular complicatio ns associated with the procedure. In order to give anatomic background to better clarifying the issue of a crossing vessel at the UPJ, we an alyzed its vascular anatomic relations in 546 kidneys divided as follo wing: 82 three-dimensional polyester resin corrosion endocasts of the collecting system together with the intrarenal arteries, 52 endocasts of the collecting system together with the intrarenal veins, 146 endoc asts of the collecting system together with the intrarenal arteries an d veins simultaneously, and 266 in situ dissected kidneys. In 65% of t he endocasts, we found a prominent artery, vein, or both in close rela tion to the ventral surface of the UPJ. Among these cases, in 45%, the relation was with the inferior segmental artery. With respect to the presence of multiple renal arteries, in only 6.8% of the cases did an inferior polar artery cross anteriorly to the UPJ. In 6.2% of the endo casts, there was a direct relation between a large vessel and the dors al surface of the UPJ. In additional 20.5% of the cases, there was a v essel crossing lower than 1.5 cm above the posterior surface of the UP J. Considering these anatomic findings, it is conceivable that many of the vessels seen during angiography in a close relation to the UPJ an d described as anomalous and etiologic in obstruction would be normal segmental arteries that do not cause UPJ obstruction. Also, on the bas is of the anatomic findings, we advise that in endopyelotomy, the inci sion along the stenotic UPJ wall be created only at its lateral aspect .