後部尿道弁20例の検討

抄録

In the past 8 years, 20 children with congenital urethral valve have been managed. All valvular structures were endoscopically confirmed as Young's type I. Clinical findings included retention, UTI with fever, failure to thrive, urge incontinence, enuresis, and in rare cases, palpable kidneys and urine ascites. Five neonates showed the lower abdonimal mass. As the associated anomalies, hypospadias was seen in 7 children. By the urographic examinations, vecico-ureteral reflux was seen in seven and prevesical ureteral atenosis in seven. In these who showed a marked dilatation and/or a prolongation of the posterior urethra with prominent bladder neck on MCU, grossly dilated upper urinary tracts due to reflux or stenosis were observed. By the cystometric examination, hypertonic intravesical pressure was observed in four of eight boys. An uninhibited contracture was seen in four children. The renal function was impaired in five boys with severe dilatation of the bilateral upper tracts. As the treatment the valve was transurethrally resected in all boys. Continuous incontinence was observed in two of four children who had been operated on for the bladder neck. There was no spontaneous improvement of the refiux after valve ablation. The histologic finding of the non-functioning kidney with massive refiux was dysplasia. The results of the management of the dilated ureters through valve resection, temporary diversion or uretero-vesiconeostomy were not all satisfactory. As the temporary diversion, the ring ureterostomy was most effective. This method requires no indwelling catheter, and the operative procedure is relatively easy for younger children. Some pathway for urine fiows to the bladder remains, which prevents the bladder from defunctionalization. Because of the thickness of the bladder wall and the hypertonic intravesical pressure it is emphasized, that neostomy is not the initial choice of operation in this entity.