RT Journal A1 SCHOLL AJ, HINMAN F, HEPLER AB, et al T1 REview of urologic surgery JF Archives of Surgery JO Archives of Surgery YR 1946 FD April 1 VO 52 IS 4 SP 487 OP 512 DO 10.1001/archsurg.1946.01230050494009 UL http://dx.doi.org/10.1001/archsurg.1946.01230050494009 AB KIDNEY  Hydronephrosis.  —Gibson1 classified the type of obstruction that causes hydronephrosis at the ureteropelvic junction, evaluated the methods of surgical treatment and emphasized the factors that contribute to the successful outcome of the operation.Obstructions of the ureteropelvic junction may be divided advantageously into three types or groups: (1) kinking and distortion at the ureteropelvic junction by extrinsic adhesions, fibrous or vascular bands or anomalous vessels; (2) intrinsic obstruction at the ureteropelvic junction by strictures from thickening of the musculature, hyperplastic fibrous tissue and a fibrous contracture producing a small stoma, and (3) another type of intrinsic obstruction from valve formation, caused by high insertion of the ureter into the pelvis. These types of obstruction may coexist. The inner caliber of the ureteropelvic junction cannot be determined accurately by external inspection or palpation. Therefore, if extrinsic obstruction is present, the surgeon should not be content in believing that it