Yoyo Reflex is a feature of:

Ans. (a) Duplicated ureterRef. Bailey and Love 27th Edition, Page 1401 and Internet SourcesDuplex Renal Pelvis and Ureter:* Incidence 1:150 Live births* Most common congenital anomaly of upper urinary system* Unilateral duplication is more common than bilateral.* Most common on left side* Most common in girls.* Increased risk is seen in siblings.* Incomplete duplex ureter with' Y' Ureter arise if ureteric bud bifurcates after initial development from mesonephric duct.* Complete cases have two buds -- one in normal position and the other in low position. Normal bud ends in trigone and there is no reflux, but in the lower bud which drains the lower pole of kidney will end more laterally in the bladder via a submucosal tunnel and will usually have vesicoureteric reflux.* If detected in children VUR is common, if detected in adults usually have no symptoms.* Reflux of urine from one ureter to other ureter instead of flowing distally is known as "Yoyo reflex" and is seen in such types of duplicated ureters and renal pelvis.