Adderhead appearance is seen in-

Ans. is 'a' i.e., Ureterocele The 'adder head' or 'cobra head' appearance on excretory urography is noted in Ureteroceleso Ureterocele is a ballooning of the distal submucosal ureter into the bladder.o Ureterocele is thought to result from congenital atresia of the ureteric orifice,o Although present front childhood the condition is often unrecognized until adult life,o It may get large enough to obstruct the vesical neck or the contralateral ureter,o It is more common in femaleso 10% cases are bilateralo Often associated with duplicate ureters (always involves the ureter draining the upper renal pole)o Almost always associated with significant hydroureteronephrosis.