Fusion malformation (referring to kidney ureter bladder is connected but from both sides into the bladder) of the kidney of the ureteropelvic junction obstruction, vesicoureteral reflux, polycystic kidney development increases the incidence of adverse, easy to be involved in abdominal trauma.
The horseshoe kidney is the most common renal fusion malformation. The renal parenchyma on either side of the spine is fused at the corresponding pole or pole, and the fusion part across the midline is the isthmus of the parenchyma or fibrous tissue of the kidney. Both sides of the ureter cross the anteromedial side of the isthmus and are usually well drained. If the obstruction is present, it is secondary to the high ureteral opening of the pelvis rather than the compression of the isthmus. There is no need to remove the isthmus during pyeloplasty.
Cross ectopic fusion kidney is the second most common renal fusion deformity. The two renal parenchyma is located on one side of the spine, one of which passes through the midline and enters the bladder at the opposite side. Pyeloplasty is required when ureteropelvic junction obstruction occurs.
Pelvic fusion kidney is an extremely rare fusion malformation. The renal tissue in the pelvic cavity consists of two sets of ureteral drainage systems. If obstruction occurs, reconstructive surgery is performed.