A Pediatric Radiology textbook and Pediatric Radiology digital library
Duplicated Kidney
Etiology: congenital
Weigert Meyer rule — Ureter draining lower pole inserts in orthotopic (normal) trigonal position + is prone to reflux — Ureter draining upper pole inserts ectopically (abnormaly) medial + inferior to lower pole moiety ureter and frequently ends in ureterocele which can cause obstruction + may insert into vagina or rectum
Imaging: drooping lily sign – obstructed nonfunctional upper pole in duplex system is displaced laterally
US: interruption of echogenic fat surrounding collecting sysem