Physical examination may reveal overt lower extremity neurological deficit and/or a hairy patch, dimple or skin tag on the spine may point to spina bifida occulta. In most children neuropathic voiding dysfunction is congenital: it must be assessed for in children with spinal dysraphism or anorectal anomalies. Cord trauma or infarction, tumours or pelvic surgery may result in acquired neuropathic voiding dysfunction. Hydronephrosis denotes dilatation of the urinary collecting system of the kidney –the pelvicalyceal system. The retrograde flow of urine from the bladder into the ureters either on bladder filling or on voiding accounts for approximately 25% of antenatally diagnosed hydronephrosis. Posterior urethral valve (PUV) accounts for almost 10% of antenatally diagnosed uropathies, and can affect the development of entire urinary tract. While many boys with PUV are detected antenatally, others present in infancy or thereafter. The quality of the urinary stream is misleading and voiding pressures in boys with PUV are as high as in normal male infants.