What happened to the four-dimensional double kidney separation?

Renal pelvis separation, intrapelvic effusion is often normal performance, general intrapelvic effusion within 10mm is considered normal, do not need further treatment. If the hydronephrosis is between 10-15mm, it should be closely observed and regularly followed up by B-ultrasound. once the hydronephrosis is more than 15mm, especially accompanied by thinning of fetal kidney parenchyma and less than 2mm, it is diagnosed as hydronephrosis. The cause should be judged. It is often the cause of fetal ureteral obstruction or abnormal ureteral valve. It is necessary to terminate pregnancy in time. Regular observation after delivery and surgical treatment if necessary.