Figure 11a. Incidentally discovered UPJO in a 36-year-old man without crossing vessels at CT. (a) Axial planar image shows left hydronephrosis and a dilated extrarenal pelvis (arrow). (b) Coronal volume-rendered image shows the inverted teardrop shape of left UPJO, which tapers inferiorly (long arrow). The left renal artery and vein are noted (short arrows).