[Segmentary dysplasia of the perivesical portion of the ureter].

Four variants of segmentary dysplasia in paravesical ureter are described: segmentary aplasia, segmentary atresia, segmentary hypoplasia, fibrous block. Segmentary dysplasia manifests in the absence of muscular layer in the wall of paravesicular ureter. In fibrous block the layer is replaced by embryonal collagen fibers. These anomalies cause ureteral obstruction and ureterohydronephrosis. 72 operative interventions were performed. Reoperations were made in such complications as vesicoureteral reflux, stenosis of ureterocystoanastomosis. It is necessary to differentiate between ectopy of the ureteral ostium, ureterocele and ureteral dysplasia in the form of segmentary hypoplasia and/or fibrous block causing the obstruction in the paravesicular ureter.