Given the task definition and input, reply with output. Given a text passage, come up with an appropriate title for it. The title should accurately represent what the main focus of the passage is. The title of a passage may be present in the first few sentences of the passage and/or be referred to multiple times in the passage. The title should be 1-5 words long.

Vesicoureteral reflux ( VUR ) , also known as vesicoureteric reflux , is a condition in which urine flows retrograde , or backward , from the bladder into the ureters / kidneys . Urine normally travels in one direction ( forward , or anterograde ) from the kidneys to the bladder via the ureters , with a 1 - way valve at the vesicoureteral ( ureteral - bladder ) junction preventing backflow . The valve is formed by oblique tunneling of the distal ureter through the wall of the bladder , creating a short length of ureter ( 1 -- 2 cm ) that can be compressed as the bladder fills . Reflux occurs if the ureter enters the bladder without sufficient tunneling , i.e. , too `` end - on '' .

Vesicoureteral reflux