Child 10 years old from the urology department with suspected nephrostomas malfunction (no urine through the nephrostomy during the day) is aimed to ultrasound. At ultrasound on the side of nephrostomy there is a severe hydronephrosis, the parenchyma is thinned to 2 mm. In the lumen of the upper renal calix the hyperechoic double linear structure is visualized type of a catheter - nephrostoma, with linear probe this structure is not visible, but such structure is visible in surrounding the upper third of the kidney tissues. In order to check the patency of nephrostomy with syringe was introduced saline in stoma and obtained the contrast effect (blizzard sign) in the renal pelvis. After the bladder visualized dilatation of the distal third of ureters, in the vesical triangle(Lieutaud triangle) on the side of hydronephrosis there is a small ureterocele and two small masses - due with several collagen injections in the past. | 
