Seminal vesicle cysts associated with ipsilateral renal agenesis. Presentation, diagnostic imaging and course

Congenital seminal vesicle cysts associated with ipsilateral renal agenesis or dysplasia are rare malformations. Even though they are more often diagnosed today due to the introduction of advanced, sectional imaging techniques as CT and MRI, no reliable data about the prevalence of this malformation are available. This study reports seven consecutive cases, with long-term follow-up in five cases (26-119 months, mean 52 months). All patients underwent sonography, excretory urography, CT and MRI. Only two of seven patients presented nonspecific symptoms of the lower urinary tract; five were asymptomatic. In all cases sonography revealed the cystic character of the retrovesical enlargement. The anatomy of the lower pelvis was most accurately shown on MRI, which depicted the ectopic insertion of the ureter into the seminal vesicle in five cases. Cysts demonstrated high signal intensities in T1- and T2-weighted spin-echo images. In five cases the CT density was over 40 HU. Whereas one patient (15 years) presented significant enlargement of the cysts 10 years after primary diagnosis with compression of the urinary bladder, four patients showed no changes of their malformation in the follow-up examinations. The present data therefore support the concept of treating only symptomatic patients. (orig.)