Ectopic ureter draining into seminal vesicle cyst: usefulness of MRI.

Ectopic ureter draining into seminal vesicle cyst is very rare congenital anomaly, which is thought to be caused by ectopic ureteral bud arising on the mesonephric duct. It is often associated with ipsilateral renal agenesis. We experienced a case of ectopic ureter draining into seminal vesicle cyst that is associated with ipsilateral renal agenesis. Generally, an invasive modality, that is, cyst puncture, cystography, or seminal vesiculography, is essential in the confirmative diagnosis of ectopic ureter. However, we could establish a definitive diagnosis with magnetic resonance imaging.